SOLAR ENERGY An Illustration of The Major Topics and Issues of

both Residential, and Commercial Solar Energy.

ABSTRACT The paper focus in all aspects of solar energy concerns.

In which the history of the technology from its early

beginnings. The paper mentions the major issues related

to the residential solar energy and the commercial solar

energy. It is covering the types and application of both

types regarding cost related issues, and the future of the

industry.

Suhail Attar

Dr. Heskia Heskiaoff

Industrial Engineering Design I & II

IENG 475-W01

IENG 476-W01

Attar, 1

Table of Contents

Introduction ................................................................................................................................................. 2

Definition .................................................................................................................................................. 2

History ....................................................................................................................................................... 2

Modern Solar Concerns ............................................................................................................................ 6

PV introduction ......................................................................................................................................... 8

Solar Thermal introduction ..................................................................................................................... 10

Residential Solar Energy .......................................................................................................................... 12

Uses and Application of Solar Thermal Panels Panels ........................................................................... 12

Uses and Application of Photovoltaics Panels ........................................................................................ 17

Cost related issues of residential solar energy. ....................................................................................... 23

Commercial Solar Energy ........................................................................................................................ 35

Uses and Application of Solar Thermal Panels Commercially ............................................................... 35

Uses and Application of PV Panels Commercially ................................................................................. 38

Cost Related Issues for Commercial Solar Plants .................................................................................. 48

Conclusion ................................................................................................................................................. 55

Works Cited ............................................................................................................................................... 61

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Introduction.

Definition.

Solar Energy is a self-explanatory term that can be explained by itself. The world solar as

it is can be defined by itself means, a more in depth definition according the Oxford Dictionary is

“Of, relating to, or determined by the sun,” originated from the Latin word Sol meaning Sun.1 In

regard to the word Energy it can be defined in a simple way, according to oxford, as a, “Power

derived from the utilization of physical or chemical resources,”2 yet as this simple way of defining

the word Energy may be very acceptable in many ways people talk, but power and energy are not

really the same when it comes from a physicist perspective. Energy is, “The stuff that allows you

to do, well, stuff,” while Power means, “a measure of how much we CAN produce,” in the case of

the solar topic power can be defined as how much energy can be produced.3 The distinction

between Energy and Power is necessary to deliver a proper definition to the term Solar Energy due

to the high usage for the term Solar Power as a synonym to it, which it can be justified if the topic

did not involve a high scientific level, such as those of Politics or Economy.

History of Solar Energy

From the definition mentioned the idea of Solar Energy has existed probably since the sun

started lighting in space. In earth, Solar Energy probably was the first source of life to most species

and still is one of the most important if not the most important sources of life. Without the Sunlight,

life as we know it would not exists. The Sunlight is a primary source of energy to plants of nearly

all types, which makes it the major factor that derives the agriculture industry in which humans

1 Search for ‘solar’ in oxforddictionaries.com 2 Search for ‘Energy’ in oxforddictionaries.com 3 SolarChoice.net.au Physics 101 – what is the difference between power and energy?

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eat and clothe from. Other than agriculture utilization of Solar Energy coming from the sun light,

it is was used for lighting, drying, and other personal care, which are still in use nowadays in a

very large scale.1

The First technical application.

Harnessing the Sunlight energy

as known today might has begun way

back in time, according to the Greek

tradition, Archimedes used reflective

mirrors to concentrate sun rays to attack

the Roman ships by burning them due

to the concentrated heat in 212 BCE.2

Regardless of the feasibility argument of whether the Death Rays of Archimedes worked or not,

the same approach has been applied Augustin Mouchot a French mathematician and physicist who

help in building steam engines between 1864 and 1878 using mirrors that were gathered in a cone-

shaped collector that concentrated the sun heat at an object heating it to boiling water temperature,

but it did not last for a long time, “The French government operated the engine for six months but

decided it was too expensive to be practical.” 3 Mouchot was able to demonstrate to an audience

how he can transform heat to cooling where he was able to power a freezer in which he made ice

with.4

1 Solar Energy Sciences and Engineering Application, see page 1 2 See what-when-how.com SOLAR THERMAL ENGINE (Inventions) 3 See what-when-how.com SOLAR THERMAL ENGINE (Inventions) 4 Cosmos: A Spacetime Odeyssey S. 1 Ep. 12

Figure 1.Painted by Giulio Parigi (1571-1635) in the

years 1599-1600 depicting Archimendes's Death Ray

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However, Mouchots works went on to directly influence John Ericsson (1803-1889) who

applied the idea of using mirror concentrated at a point.1 Between 1871 and 1878 Ericsson invented

a steam engine that uses mirrors pointed at a water filled tube, but the engines were running too

slow, which led him to convert them into coal engines to avoid the financial lost.2

The First Successful Attempt.

The major step toward creating a solar plant as known today was made by Frank Shuman

who was also influenced by Mouchots in 1912.3 Shuman who was a wealthy investor and a self-

taught engineer formed the Sun Power Company in 1906, and at the beginning he tested the idea

in a plant where he applied the idea of Ericsson directing the sunlight via mirrors shaped as

parabolic toward a tube, near his home in Philadelphia, Pennsylvania. He then he used a Suburb

of Cairo, Egypt called Maadi to conduct the experiment in large scale and the results were

exceptional, “The company finally constructed the improved plant in Meadi, Egypt, a farming

1 See Kryza, The Power of Light, p. 147 2 See what-when-how.com SOLAR THERMAL ENGINE (Inventions) 3 See Kryza, The Power of Light, p. 147

Figure 2. THE 1878 SUN-ENGINE - PRODUCING

ICE FROM HEAT - PRESENTATION-COPY from

Solar Heat and industrial applications. Second Edition

by Mouchot, A

Figure 3 Augustin Mouchot

Image credit: Wikipedia

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district on the Nile River. Five solar collectors, spaced 25 feet apart, were built in a north-south

line. Each was about 200 feet long and 10 feet wide. Trough-shaped reflectors were made of

mirrors held in place by brass springs that expanded and contracted with changing temperatures.

The parabolic mirrors shifted automatically so that the rays were always focused on the boiler.

Inside the 15-inch boiler that ran down the middle of the collector, water was heated and converted

to steam. The engine produced more than 55 horsepower, which was enough to pump 6,000 gallons

of water per minute.” 1 However, due to World War I the project was suspended and unfortunately

Shuman died before the war ended, and such a successful story was unfortunately lost for a long

time.2

This approach is commonly known today as Concentrated Solar Power (CSP), and thanks

to the mentioned scientists and engineers it can be found in many parts of the world nowadays.

CSP is being applied to a number of solar thermal plants, such as the Gemasolar Thermosolar Plant

1 See what-when-how.com SOLAR THERMAL ENGINE (Inventions) 2 Cosmos: A Spacetime Odeyssey S. 1 Ep. 12

Figure 5Frank Shuman - Hagley

Museum and Library - "Direct Acting

Solar Engine: The Prime Mover of the

Immediate Future" published in 1907,

pg. 2

Figure 4 The News from the New York Times in 2 July 1916

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located at Fuentes de Andalucía, Sevilla, Spain, and Ivanpah Solar Power Facility located at

Ivanpah, San Bernardino County, California, USA. These plants uses mirror directed at a centrals

tower in which it would allocate the heat from the sun toward a tower or an object and produces

power. (CSP) is in use in many parts of the world mostly in Spain. Due to a Greek legend a great

invention to humans was born and it is now challenging the forces of fossil fuel that has been, for

a long time destroying the efforts to come up with the alternative Energy Source.

Modern Solar Energy Concerns.

Since that start of the industrial revolution the value of energy has risen up due to the ability

of energy to increase the production of goods, and boost transportation to unprecedented levels.

After almost more than 150 year from the industrial revolution the world has changed very much

even though the primary energy sources that is carbon based are still in use and by far more than

any other energy sources. It is the technological advance nowadays and during the 150 years that

Figure 6 The Gemasolar solar thermal power plant

with a molten salt heat storage system in Seville Spain,

which produces 20MW, enough to power 25,000 homes

| Image credit: Wikipedia

Figure 7 Ivanpah Solar Electric

Generating System from Daily Tech

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had the noticeable amount of change that served the ways of which, extracting high amounts of

energy from those sources and how it can be used in an efficient way.

However, in recent years the world has seen a high increase in the topic of clean alternative

energy source and how it can help reducing the harmful effects of carbon based energy sources.1

In addition, the belief that these alternative sources are renewable and cheaper makes it a very

interesting topic to be considered for it benefits. Those economic, environmental, and

technological outcomes have made this issue a very important especially that the world is

witnessing a growth in industrialization and urbanization, in countries such as India, and China

where there is a high demand for a better quality of life, similar to those in rich parts of the world.2

The Technology of Harnessing the Sun’s Energy.

The Sun send great amounts of energy towards earth in about 1×1017 W, according to Paul

A. Lynn author of Electricity from Sunlight, “the Sun provides in about an hour the present energy

requirement of the entire human population for a whole year.”3 Not all of this amount can be

harnessed due to the Earth surface being more than 70% water, yet still the Sun can produce great

amounts of energy. The Sun delivers about a 1000 W/m2 at sea level which is known as the power

density, yet the Sun power density is 1366W/m2 on the atmosphere surface.4 However, due to the

shape of the earth the average power density known as annual mean insolation is about 342W/m2,

1 Solar Energy Sciences and Engineering Application, see page 1. 2 Solar Energy Sciences and Engineering Application, see page 2. 3 Electricity from Sunlight an Introduction to Photovoltaic, see page 6. 4 Electricity from Sunlight an Introduction to Photovoltaic, see page 6 and 7.

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where it is concentrated at most in

the equator area with about 430

W/m2 and get reduced more towards

the Polar Regions.1

There are two main types of

transforming the sun light to energy

that can be utilized in many ways.

These are the Photovoltaic Cells, and

Solar Thermal Collectors. Both types

come in many shapes and sizes for so

many uses. There are many

technological levels of solar panels

starting from the ones that are very

basic and can be made at home, and

ones that are very complicated and

requires a high level of manufacturing.

Photovoltaic.

The Photovoltaic cells produces energy by allocating the Sun photons and transforming

them in to electrons that gives power to the electronic devices. The cells are made of semiconductor

material mostly based on silicon and germanium. As simple the idea of Photovoltaic may imply,

1 Electricity from Sunlight an Introduction to Photovoltaic see page 7.

Figure 8 Annual mean insolation at the top of Earth's

atmosphere (top) and at the planet's surface. Owned by

William M. Connolley using HadCM3 data

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the idea was not really an easy one where it did not require much

work, rather it is the work of, “half a century” in which a great

amount of work and research was made to reach these level.1 The

PV effect was first discovered by French scientist Edmond

Becquerel in 1839 where he shone light at an electrode in an

electrolyte solution, but a proper understanding to the phenomena

was due to “quantum theory practical application to useful PV

device had to await the arrival of semiconductor electronics in the

1950s. Thus, there was a gap of over a hundred years between

Becquerel’s initial discovery and the development of the PV as

we know it today.”2 The first photovoltaic module as we know it

today was made by Bell Laboratories in 1954, where, “it was

billed as a solar battery and was mostly just a curiosity as it was too expensive to gain widespread

use.”3

The way PV functions

is by having a semiconductor

material most likely silicon

and treat it in a special way to

form an electric field one side

is positive and the other is

negative. When the light hit

1 Electricity from Sunlight an Introduction to Photovoltaic see page 12-17. 2 Electricity from Sunlight an Introduction to Photovoltaic see page 12-17. 3 How do Photovoltaics Work? by Gil Knier, see science.nasa.gov/science-news/science-at-nasa/2002/solarcells/

Figure 9Portrait of physicist

Alexandre Edmond Becquerel

printed by Charles Jeremie

Fuhr.

Figure 10 the operation of a basic photovoltaic cell

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the cells that were made of silicon it goes through the two sides, the

positive one first and the negative one second, where the electron of

the photons go through and reach the current. Thus it creates an

electric current and produces electricity.1 However, the most popular

form of PV panels is the single junction or interface, which, “only

photons whose energy is equal to or greater than the band gap of the

cell material can free an electron for an electric circuit. In other words,

the photovoltaic response of single-junction cells is limited to the

portion of the sun's spectrum whose energy is above the band gap of

the absorbing material, and lower-energy photons are not used.”2

The article author from NASA illustrates the way in which this

limitation can be managed is to use the multifunction one, which

uses a number of cells. “Much of today's research in multifunction

cells focuses on gallium arsenide as one (or all) of the component

cells. Such cells have reached efficiencies of around 35% under

concentrated sunlight.”3

Solar Thermal Collectors.

Solar Thermal Collectors were mentioned heavily in the

solar energy history. Also as mentioned many of the technology

is still has not changed. However, the history part of the paper mentions mainly the Concentrated

Solar Power (CSP) type, which heavily depends on mirrors that reflects the Sunlight on a point

1 How do Photovoltaics Work? by Gil Knier, see science.nasa.gov/science-news/science-at-nasa/2002/solarcells/ 2 How do Photovoltaics Work? by Gil Knier, see science.nasa.gov/science-news/science-at-nasa/2002/solarcells/ 3 How do Photovoltaics Work? by Gil Knier, see science.nasa.gov/science-news/science-at-nasa/2002/solarcells/

Figure 11 PV devices use

a single junction

Figure 12 multifunction

device is a stack of individual

single-junction cells in

descending order of band gap

(Eg)

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where it would heat a fluid inside a pipe to generate electricity from the circulation of the fluid.

The same way is the other type, which is made of a box that have a glass that allow the Sun’s heat

to go inside and does not come out allocating a high amount of heat that it heats the pipes made

of copper mostly causing the fluid to circulate. It is mostly used for heat generation.

Solar Panel Efficiency.

The efficiency of the solar panel is determent by the amount of sunlight that becomes

electricity, in which it is donated by the percentage of the amount of solar energy that gets

transformed into electric power.1 Most of the solar panels can be between 11% and 15% efficient,2

1 Solar Panel Efficiency. Go to http://pureenergies.com/us/how-solar-works/solar-panel-efficiency/ 2 Solar Panel Efficiency. Go to http://pureenergies.com/us/how-solar-works/solar-panel-efficiency/

Figure 13 Advanced Solar Collectors from Alternate Energy Technologies

AE- Series Solar Collectors

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while some go up to 21.57% and low to 3.60%.1 One can infer that with the higher efficiency the

less area can be used, which is considered the main factor of determining what system is the best

for a particular application whether residential or commercial. In scientific labs scientist have

developed some modules that reach up to 40%.

Residential Solar Energy.

The uses of Solar Energy in homes is a very diverse type of utilization, in which it involves

a high level of creativity depending in the situation of the place and many other factors. As

mentioned there are two main types of harnessing the Sun Energy, which are Solar Thermal Panels

and Photovoltaic Panels. Depending on the use these two types can be more efficient and cost

effective than the other mainly the factors of having one better than the other is due to its capability

to harness the Sun Energy and maintenance related issues.

Uses and Application of Solar Thermal Panels.

Most of the uses of Solar Thermal is for heating purposes. The most common ones for

heating is space heating and water heating using the Solar Thermal Panels. The idea of it is to

make the hot Sun radiation concentrated at some kind of a collector, which heats air and water.

The Air-based delivery system is considered the simplest system one that heats air that is drawn

directly into rooms. The Air-based system comes in two main types one by natural ventilation

where the air moves by itself in the pipes or the air path that passes between or under a sun heated

medium to the room, and the other type is the forced ventilation type which uses an air fan that

moves the air.2 This system is appropriate in a winter with many sunny days, which means it must

1 Solar Panel Comparison Table. Go to http://sroeco.com/solar/table/ 2 Solar Technology: The Earthscan Expert Guide to Using Solar Energy For Heating, Cooling and Electricity, See

Page 97.

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have some kind of location requirement as shown in the map in figure 8, yet this does not mean

that it would not work in some areas, rather it will work if some adjustment were done such as

increasing the panels area so it could collect more sun radiation. This system requires that the

building it is heating having a sufficient thermal mass to store the heat overnight.1

Methods used in Air-based system.

1. Window box collector.

This system is very

simple, and very easy to

work. It functions by

placing the collators on

the window, in which

the window is open so

that it allows the collector to interact with the air of the room. The collector uses

the air from the home and depending in the ventilation method whether forced

by a fan or not the air will circulate around the sun heated multilayered panel.

“The collector’s layers are, from front to back:glazing, an upper airspace, a

black metal plate, a lower air space, insulation, and base”2

1 Solar Technology: The Earthscan Expert Guide to Using Solar Energy For Heating, Cooling and Electricity, See

Page 98. 2 Solar Technology: The Earthscan Expert Guide to Using Solar Energy For Heating, Cooling and Electricity, See

Page 98.

Figure 14 Window box collector. from

exposingtruth.com

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2. Roof-or wall-mounted collectors. Unlike the Window box collector. This one

uses external air, and the air circulates by a fan that is in many cases uses electric

power drawn from a small PV solar panel making the whole system depending

in solar energy. There are two types of designs of the system, one contains

materials with thousands of tiny capillaries, which absorb the sun’s heat. “The

heated incoming air drawn through ducts into the building where it is

discharged around the floor level of the lower floor.”1 The other design is a one

that is glazed and contains a black plate that heats air much like the window

box.

1 Solar Technology: The Earthscan Expert Guide to Using Solar Energy For Heating, Cooling and Electricity, See

Page 98.

Figure 15 Solar Hot Air Collectors can be mounted on the roof

or/and on the south side of the house

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Water-based delivery system.

Mostly the system function with another source of energy “pre heating the water so another

heat source has less work to do.”1 The hybrid system is combined with electrical, gas or biomass

power sources. Similar to the air-base system the larger the area of the sun panel the faster the

results will show in heating the water, which is stored in tank that gets heated and also depending

on the house usage of hot water. Some cold areas need four times the requirement when compared

with another source. Most of the time of the year the water can be heated mostly by the sun

collectors, yet in the winter the opposite can be true in very cold places. If the combined fuel was

not very efficient such as wood boilers then a large tank is required for the system, so it could store

a higher temperature.

1 Solar Technology: The Earthscan Expert Guide to Using Solar Energy For Heating, Cooling and Electricity, See

Page 100.

Figure 16 A solar water heating system form Florida Solar Energy

Center at UCF fsec.ucf.edu

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The proper area of a hybrid collector in a place located at Austria (near southern Europe)

for both mentioned system is 12-20 m2 (129-215 ft2) for a single family house. In a well-insulated

house the system can cove 40% of heat demand depending also on the area on the collector which

it could reach 100%.1

Other Solar thermal application for homes.

1. Heat pumps for cooling. This system uses the regular system mentioned, but with some

help from electricity is reverse itself and cool a home instead of heating it.

2. Solar Drying. This system is used a long time ago for drying food, yet for a more

protected food and possibly a

faster result the food is put in

side a solar dryer. The solar

dryer is simply a box that is

with a plastic or glass cover

that have some open spaces to

let warm air to go through it,

so it absorbs the liquid from

the food. This system is used

Salsa in large scales where a

tent functions similar to a box.

1 Solar Technology: The Earthscan Expert Guide to Using Solar Energy For Heating, Cooling and Electricity, See

Page 102.

Figure 17 Solar Food Dehydrator from

thisbahamianlife.com

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Figure 18 design of a solar cooker from

ruthtrumpold.id.au

3. Solar pasteurization. This method is used in poor countries where it is hard to find pure

water to drink. The method takes container filed with water put a center of a collector

heating it by the sun to 60ο C (149ο F) for about 7 minutes, so it kills all the germs and

viruses.

4. Solar Cocking. Solar

cocking is a simple way of

cooking that only needs to

put a cooking pot in what is

called a cooking dish that

will collect the sun

radiation and direct it to

ward a point where the pot

is located.

Uses and Application of Photovoltaics Panels.

The most efficient use for the residential application is the Building Integrated System

(BIPV), which is a grid connected system (the system where the supply of electricity can be gained

from a central power plant in the case of insufficient power came from the panels). The grid

connected system will be explained in the installation part of this part. BIPV is limited to the

budget of the home owner and the surface available to put the panels on them that is why it is very

recommended that the system be integrated with the building of the home, in which it should,

“form a part of the roof, cladding, overhanging shading or windows of a building.”1 However, this

1 Solar Technology: The Earthscan Expert Guide to Using Solar Energy For Heating, Cooling and Electricity, See Page 144.

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amount of integration might be very hard to deal with in relation to the quality of the home

products, which is why in Japan some solar energy companies bought construction companies, so

it would guarantee that the products are well made and would not cause leakage and have high

resistance to fire.1

The other popular type in the regular PV panels used in roof tops that are not integrated to

the design of the home. This type has some advantages over the integrated one, mainly they are

being easy to install and uninstall for maintenance issues, and they might function better by being

placed in a way that the sun would cover it for a longer time, which will be very proper for a low

budget. It is fairly simple to see why they could be easy to install and reinstall because they do not

come attached to the build of the home, where it would not be necessary to take out the PV layer

of the roof and leave the home subject to an improperly protected roof, the same case if it was

integrated to a window. However, it is fair to say that the BIPV found solution to the issue, yet still

it is easier to install and reinstall. The main issue is the budgeting issue, when comparing the two

types, by looking at the main purpose of placing the panels, which is absorbing the most possible

sunlight. In the BIPV there would be many places that the sunlight will not reach for a long making

a relatively useless extra space.

However, as mentioned where construction companies are being bought by solar PV

companies, the research and development of the BIPV will become better with time because it will

become, and in many cases it has become aesthetically appealing plus cheaper. It is very highly

predicted that in the future the growth BIPV will rise and it is already being seen in many places

around the world. According to Electricity from the sunlight by Paul A. Lynn, “Future generations

1 Solar Technology: The Earthscan Expert Guide to Using Solar Energy For Heating, Cooling and Electricity, See Page 144.

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will find it entirely natural to see PV arrays on roofs and facades, in gardens and parks… and as

electricity- generated windows and screens inside homes, schools, offices, and public buildings,

most will be grid-connected,” he writes, “PV will become increasingly a part of the urban

experience.”1

Installation of Solar Panels.

Solar thermal installation.

1 Electricity from Sunlight an Introduction to Photovoltaic, see page 115

Figure 19 Shake Shack Westbury, NY which applies BIPV from shakeshack.com/location/Westbury/

Figure 21 BP SOLAR SHOWCASE

BIRMINGHAM, ENGLAND. It was designed

and built in just six weeks to coincide with the G8

Summit of World Leaders held in Birmingham in

May 1998. It applies the BIPV system.

Figure 20 unintegrated roof top PV, from

http://ccsolar.net/

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The solar thermal installation part is in general less complicated when compared to PV.

The solar thermal panels’ installation and manufacturing are illustrated from the part where the

uses and application part in, which nearly all kinds of solar thermal uses related to homes uses are

shown. However, installing the solar thermal is mostly done by placing the panels at the sunlight

and connecting the panels to the heating source or the object that needs to be heated. Mainly the

components needed for the fairly complicated version of the solar thermal application, which is

the water heating one are as follows.1

The Solar Collectors or Solar Thermal Panels.

Solar Pump Station.

A System controller.

Expansion Vessel.

Solar fluid to fill the system.

You may see figure 16.

Photovoltaic installation.

There are mainly two types of PV to be installed in a home one is the on grid, and the other

is the off grid. They all are very similar in installation, yet there are some differences that can make

one bitter than the other. The meaning of on grid and off grid is fairly simple as their names may

apply. The on grid system is the system that uses the solar energy with conjunction with the main

power plant to generate power, where it can be helpful when there is insufficient sunlight in the

winter or at night, so the grid can supply the home with power needed. The other on grid can be

helpful is when in a very sunny environment or times of the year such as summer there would be

1 Grant Solar Thermal Installation procedure. See https://youtu.be/i8kJRnv-hrI

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an excess amount of power that reached beyond the demand of the house. This issue of excessive

produced power is solved by the Net metering system, which protects these amount of power

from being wasted and feed the grid for a compensation, or reusing in the future or probably the

night of the sunny day.1 On the other hand, the off grid system is very much concerned with being

isolated, it may not enjoy the availability of a grid connected system, yet in sunny places around

the world a properly installed off grid system can be by fare very economical.

In installation an on grid system there are a number of component that needs to be

illustrated and explained how they work together as follow.

1. The PV solar Panels.

2. MPPT charge collector: this takes the power from the solar panels and convert DC

to DC, so it can have the right voltage for the system and the batteries.

3. Grid-tie Inverter: this is probably the main component after the panel. It is an

inverter that takes solar power from solar panels and converts the DC to AC and

supply the home, and in feed the grid in the case excess amount many system stop

at this point especially if the home owner was on a low budget and/or does not want

to attach a battery for other technological purposes such as net metering, yet in a

system with batteries the grid-tie inverter supply the battery as well.

4. Normal Inverter: this come in the fourth main step where probably comes after a

breaker for safety issues due to the battery. This invertor interact with the battery,

and it is not connected to the solar panel at all. It takes the power from the batteries

1 How to Solar Power Your Home / House #1 - On Grid vs Off Grid, go to https://youtu.be/bzcTFUcXwIY

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and convert them into AC and supply the home, and in some systems supply the

grid as well.

5. Batteries.

6. Energy monitor. It would show the energy consumption for the home.

A more advanced system is a one that uses micro inverter attached to each panel, where

it would work more efficiently, in which it would get the maximum power from each cell

and would not affect the overall power generation if parts of the panels did not get sufficient

Figure 22 grid tied solar system for aurorapower.net

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sunlight. The other reason is when having one invertor the whole system becomes subject

to failure if the inverter had an issue.1

The off grid system is mainly only concerned with the solar panels, the inventor and

the batteries. In this case all of the mentioned components have to be bigger in size so it

can be self-sufficient under all circumstances.

Cost related issues of residential solar energy.

Installing a solar energy system whether PV or solar thermal, can be very costly, yet the

future benefit of such an issue is very appealing. In addition to that thanks to governmental tax

credits one might end up paying a very small amount compared to the whole amount without

1 How to Solar Power Your Home / House #1 - On Grid vs Off Grid, go to https://youtu.be/bzcTFUcXwIY

Figure 23 Off-Grid Solar system aurorapower.net

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government support. The main focus of this paper is to look into the USA and more specifically

the state of New York.

An average monthly home energy consumption in the US is about 903 kWh and in New

York it is 656 kWh, luckily those living in warm places and suffer high energy consumption, such

as Florida with 1081 kWh, Arizona with 1061 kWh, and Louisiana with the highest 1254 kWh.1

All these states have so many issues to conceder such the amount of Sunshine and the proper type

of system it will benefit the most. Of course for the residential application the warm states will

prefer PV because they are not in the need for heat at all probably the only heating they might have

would be available by an air conditioner heater which will be in use for few days in the winter.

The average monthly bill in the US is about $107.28 and it is $106.14 in New York where

it is considered to be high compared to the average monthly energy consumption, yet not as much

as Hawaii, which pays an average of $ 203.15 and it consume monthly on an average of 531 kWh

there are many factors that play a role in the pricings, such as sunshine, availability of fuel,

population and many other factors.

Net Metering

In illustrating the cost related issue of cost in its relation to solar energy, the concept of Net

Metering has to be explained. Net metering was briefly mentioned in the second part of this paper

as a solution for the excessive amounts of energy production a home’s renewable energy system

produces. A proper example in the local environment is the PSEG Solar Metering system which

is the power company of Long Island, NY, which follows the New York State Net Metering Law

1 How Much Electricity Do You Use Each Month? Go to http://insideenergy.org/2014/05/22/using-energy-how-much-electricity-do-you-use-each-month/

Attar, 25

which have a limit of 25 kW for residential, 2 MW for non-residential for power produced by solar

PV. PSGE credits the customer in the next month’s bill. The meter must be adjusted so it can be

reversed, otherwise there would not be a benefit usually this happens by replacing the standard

kilowatt-hour meter by a net meter, “which accurately registers the flow of electricity in either

direction.”1 The consumer is also able to store the energy in an energy bank which happens in the

case of a home produced more energy than it consumes over the month which can be withdrawn

in the incoming months.

The high demand generated a high competition in the PV installation market, which created

many contractors that provide installation for PV. Those companies can be local, such as Sunation

of Long Island, NY or national, such as Solar City. There are contractors that offer a variety of

1 Solar Net Metering for PSEG. Go to https://www.psegliny.com/page.cfm/Efficiency/Renewables/Solar/NetMetering

Figure 24 Basic illustration of Saving Money with Solar Energy from solar-energy-at-home.com

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Figure 25 According to NPD

Solarbuzz, Yingli Green Energy

maintained leading module supplier

ranking in 2013. Seven of the Top-10

were c-Si module makers based in

China. From pv-tech.org

choices of brands, specifications and qualities of solar panels and system. In addition, those

contractors will be offering a number of ways they would lease the system they would design.

Figure 26 “U.S. Solar Market Insight:

2013 Year in Review from SEIA/GTM

Research

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Cost of PV installation in Long Island. In a pricing example from Sunation a solar energy

company of Long Island, NY, the following is shown for Solar System 8700 Watt Capacity (30 x

290 watt modules). (The breakdown for solar thermal is similar.)

“Price varies with equipment selection and size of system - your actual costs will differ

from what's below. This is just an example.

Total Retail Price $32,309

NY State Tax Credit

(25% of net cost max. $5,000) $5,000**

Federal Tax Credit

(30% of net) $8,400

Total Investment $18,909

Est. Electrical Production/yr $2,375***

Est. Increased Value of Property $47,500

Simple "TAX FREE"

Return On Investment 16.2%

Simple Payback 6.1 years

Projected Lifetime Savings $106,875*

*Based on a 3% annual escalation rate.

**NY State Tax Credit can be carried over multiple years if needed.

***Estimated savings based on PSEG Clean Power Estimator.”1

1 PV Pricing Example from Sunation Solar Systems. Go to http://sunationsolarsystems.com/Pricing

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Figure 27 shows a part of the top 100 US Solar system contractors. The Sunation of

Oakdale, NY located in Long Island is ranked 40th nationally.1 However, to get a proper idea of

what a customer needs to go through to buy or lease a solar panel system the contractor on top

process might be the most helpful. SolarCity process of installation is done in eight steps as

follows.2

1. Welcome. In this step the customers give the company their home bills to the company

and the company would manage to know what type of system would be better of the

home, in which a consultant would map out the home needs and take care of all the

1 2014 Top 100 Residential Solar Contractors. Go to http://www.solarpowerworldonline.com/2014-top-400-solar-contractors/2014-top-100-residential-solar-contractors/ 2 Why SolarCity? Go to http://www.solarcity.com/

Figure 27 2014 The first 10 of Top 100 Residential Solar Contractors from

solarpowerworldonline.com

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necessary permits and inspection. Also after all agreements are done the customers

would be able to check the status of their project online or on a smart phone application.

2. Site Audit. In this step a site auditor will visit the home of the customers to take the

necessary measurement and gather technical information, so the final project would

meet the home aesthetic, and energy needs.

3. System Design. The engineers will then use the information gathered by the auditors

and custom design the system.

4. Building Permit. In this step the company will submit the plans, to get the local permits

and the Home Owner Association approval.

5. Installation.

6. System Inspection. The company will schedule inspection with the local building

department.

7. Utility Inspection. In this step the company will go ahead and inspect the system, so

they connect it to the grid.

8. Turning it on.

The average solar panel system for SolarCity is 5.87 kW and cost about $29,916 with price per

Watt is about $5 depending on the system, when leased the price might increase by 70% because

most of those who would lease would not get the Federal 30% tax credits.1

Buy or Lease, and Tax Credits issues.

The issue of buying or leasing is related to the customer’s financial abilities. However,

buying is in general would make the most economic benefit, in which the return on the investment

1 What is the price cost for a SolarCity PV system? Go to http://www.freecleansolar.com/What-is-the-price-cost-for-

a-SolarCity-PV-system-s/4620.htm

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would be between 10% and 30% each year.1 If the customer is willing to pay the full amount or

take a solar loan then buying is the choice, if the customer does not have the capital then Leasing

is the choice.

The Tax credit issue is one of the major factors in the buying or leasing decision. If ones

IRS tax amount due is greater than the federal solar tax credit then buying is the option, but if the

IRS tax amount due is less than the federal solar tax credit then leasing is the option because there

will be no federal solar tax credit, and in most cases one needs to have a credit score greater than

650.2

Federal Tax Credits (30%) requirement.

For a PV or any Solar-electric system.3

1. If the system was in service after 2008, there would be no maximum credit.

2. The system has to be in effect between January 1, 2006, and December 31, 2016.

3. The system does not have to be serving tax payer’s principal residence.

For a Solar water-heating system.4

1. If the system was in service after 2008, there would be no maximum credit.

2. The system has to be in effect between January 1, 2006, and December 31, 2016.

1 Should you buy or lease your solar panel system? Go to https://youtu.be/nA9PhZaIee4

2 Should you buy or lease your solar panel system? Go to https://youtu.be/nA9PhZaIee4 or https://www.energysage.com/solar/financing/should-you-buy-or-lease-your-solar-panel-system 3 RESIDENTIAL RENEWABLE ENERGY TAX CREDIT. Go to http://energy.gov/savings/residential-renewable-energy-tax-credit 4 RESIDENTIAL RENEWABLE ENERGY TAX CREDIT. Go to http://energy.gov/savings/residential-renewable-energy-tax-credit

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3. “Equipment must be certified for performance by the Solar Rating Certification

Corporation (SRCC) or a comparable entity endorsed by the government of the state in

which the property is installed.”1

4. “At least half the energy used to heat the dwelling's water must be from solar in order for

the solar water-heating property expenditures to be eligible.”2

5. The heating system must not be for heating pools and hot tubs.

6. The system does not have to be serving tax payer’s principal residence.

New York State Solar Energy System Equipment Credit (25%) Requirement.

The credit is 25% of the equipment expenditures with a limit of $5000, and the credit is

nonrefundable, but if the credit was greater than tax due it can be, “carried over for up to five

years.”3 According to the NYS Department of Taxation and Finance, one is entitled to the benefit

if, “purchased solar energy system equipment, entered into a written agreement for the lease of

solar energy system equipment, or entered into a written agreement that spans at least ten years for

the purchase of power generated by solar energy system equipment not owned you.”4 System that

1 RESIDENTIAL RENEWABLE ENERGY TAX CREDIT. Go to http://energy.gov/savings/residential-renewable-energy-tax-credit 2 RESIDENTIAL RENEWABLE ENERGY TAX CREDIT. Go to http://energy.gov/savings/residential-renewable-energy-tax-credit 3 From NYS Department of Taxation and Finance Solar Energy System Equipment Credit. Go to http://www.tax.ny.gov/pit/credits/solar_energy_system_equipment_credit.htm 4 From NYS Department of Taxation and Finance Solar Energy System Equipment Credit. Go to http://www.tax.ny.gov/pit/credits/solar_energy_system_equipment_credit.htm

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are used for heating, cooling, hot water, or electricity for residential use are the only ones allowed

to get the benefit.1

New York State for Solar Panel Loan for Residential Installation.2

The loan for home owners is up to $13,000, and can reach $25,000 if the cost-effectiveness

was high for periods of 5, 10, and 15 years. The loan options are:

OPTION 1: Residential and Small Business/Not-for Profit On-Bill Recovery Loan.

Current interest rate is 3.49%.

The payment will be listed in the utility bill. Which will be monthly instalments.

“Monthly payments may not exceed the estimated energy cost savings from the energy

upgrades, which means the energy savings may cover most or all of your loan payment.”

If the home was sold the unpaid amount may be transferred to the new home owner.

OPTION 2: Residential Smart Energy Loan.

Current interest rate is 3.99%, or 3.49% if paid in automatic payment.

The payment are made directly to New York State Energy Research and Development

Authority.

A hypothetical home example for an average American house.

A Photovoltaic System.

The average US house size is about 2,520 square feet, with a footprint of about 24’x50’.3

The average US industry price of installation is $4.80 per Watt.4 However, this customer of long

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island is on a tight budget and aims to spend about $25,000 and decides to go with the average

system that will cost about $4.80 per Watt. This means that the customer will have a system of

5000 watts which means that 500 square feet of the roof top, according to Sunation, “The average

system requires between 400 and 600 square feet of clean roof area or about 100 square feet per

1000 watts.”5

According to the mentioned requirements and purchasing recommendation in this section

there are 2 major options that depend on the situation of the customer.

1. The buying option, which is if the customer already have the money on hand, or gets a loan

depending on credit score. This option will allow the customer to get his or her tax credits

if qualified, and for this intuitive example the customer taxes due are greater that the credit

which is greater than $7,500.

Installation cost (including batteries) $25,000

Fed Tax Credit (30%) $7,500

NYS tax credit (25% with $5000 limit) $5,000

Total Investment $12,500

The customer then might not need to buy the system and prefers to finance it with an NY-

Sun Incentive Program Loan. To avoid the complication the customer shows to go with the second

option and to get the lower interest rate of 3.49% he choose to enroll in automatic payment, and to

make the most out of his loan he chooses to pay it in 15 years. Thus, he will have a Loan of

1 From NYS Department of Taxation and Finance Solar Energy System Equipment Credit. Go to http://www.tax.ny.gov/pit/credits/solar_energy_system_equipment_credit.htm 2 Financing Options for NY-Sun Incentive Program. Go to http://ny-sun.ny.gov/Get-Solar/NY-Sun-Financing 3 How much does it cost to build a single-family house? Go to http://www.fixr.com/costs/build-single-family-house 4 What is the price cost for a SolarCity PV system? Go to http://www.freecleansolar.com/What-is-the-price-cost-for-a-SolarCity-PV-system-s/4620.htm 5 SOLAR SYSTEMS COSTS. Go to http://sunationsolarsystems.com/Pricing

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$12,500, 15 years, and an interest rate of 3.49%, in which make his monthly payment comes to

be $89.31 which is calculated by i= 0.0349/12 = 0.00291, n= 12 x 15 = 180 months, the monthly

payment would be

PMT= P * (i / (1 - (1 + i)-n)) = 12,500 * (0.00291/ (1 - (1 + 0.0029)-180)) = $89.31

2. The second way the customer would pay for the system is by leasing it. It this not very

reasonable for a customer to lease a unless the company was offering free installation with

the system because the customer would get the state credit, yet Federal tax credit will go

to the company as the provider.1 In this case, the customer would end up paying about

$6.81 per watt, which means he might end up with a 3700 watt system paying more than

20,000.2

With the current status of the market it seems that this time is indeed due to all the government

benefit and the rapidly lower prices of PV a customer must act.

A thermal heating system.

The breakdown for a solar thermal heating system is similar to the PV, yet in the heating

system the customer this time aims to have a system that is appropriate to his home needs. He then

goes online on fixr.com and fill in a form to see what type of information he needs to give to get a

proper system. The information that the customer provided were the size of water heater, whether

the heater will heat pools or hot tubs, the location of the heater, and other question regarding project

readiness and timing. Finally, after dealing with a consultant the home owner got a price and it

1 Federal Solar Tax Credit. go to http://pureenergies.com/us/solar-financing/federal-solar-tax-credit/ 2 The Lowest Cost For The Best Solar Panels. Go to http://www.freecleansolar.com/What-is-the-price-cost-for-a-SolarCity-PV-system-s/4620.htm

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was $17,000.1 Because the system has to be accounted for most of the heating produced to get the

Federal Tax Credit.

Cost of installation $17,000

Fed Tax Credit (30%) $5,100

NYS tax credit (25% with $5000 limit) $4,250

Total Investment $7,650

From this point all the matters illustrated in the PV home would fit the same criteria.

Note. All the information in the hypothetical home are from information of the preceding topics

of Cost related issues of residential solar energy part, unless the source is referred with a foot note.

Commercial Solar Energy.

Commercial solar energy is very similar in many characteristics to the residential ones, in

which it is very diverse and have many types of solutions. Similarly, it functions with Solar

Thermal Technology and Photovoltaic.

Uses and Application of Solar Thermal Panels Commercially.

There are mainly two type of solar thermal uses for a large scale commercial uses. The first

one is the one discussed briefly in the introduction which is the Concentrated Solar Power System

1 How much does it cost to install a solar water heater? Go to http://www.fixr.com/costs/solar-water-heater-installation

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(CSP), and the other is the District Solar Space Heating. Those two are very distinct and functions

differently than each other.

1. The Concentrated Solar Power System (CSP).

In reference to figures 6 and 7, this system is found in a very large scale in many

places around the world. It is simply as mentioned in the history part of the paper uses

mirrors directed at a tube or a central tower heating a fluid that can handle heat well,

which could be oil or molten salt. Then, the fluid is sent to heat water that makes a

steam that pushes a turbine in power system resulting in a production of power making

electricity. Both the steam of the water and the hot fluid is recycled and used again in

the process. The main types of CSP are Towers, Dishes, Linear Mirrors, and Parabolic

Trots.1 According to the U.S. Department of Energy “Sunny skies and hot tempuras

make the Southwest of the US an ideal place for these kind of power plants, many CSP

can be built in the next several years and a single plant can generate 250 MW or more,

which is enough to 90,000 homes.”2

The downside is that CSP is storing the energy whether electric or heat is very

expensive, yet there is an area of development for the coming years. For the US most

of these are located in the desert, where there is a very small of the population compared

to the other parts of the US, in which it creates a challenge to the development of this

1 Energy 101: Concentrating Solar Power from U.S. Department of Energy YouTube channel. See

https://youtu.be/rO5rUqeCFY4. 2 Energy 101: Concentrating Solar Power from U.S. Department of Energy YouTube channel. See

https://youtu.be/rO5rUqeCFY4.

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type energy where people do not live close by meaning that the electricity would need

to be connected for very long distances.1

2. District Solar Space Heating.

DSSH is a very beneficial way of generating power where it functions similar to

the home solar space heating, yet it distribute the heat to a large scale limited to a district

or a neighborhood for about 300 homes.2 It would not be found in the US, rather it is

found in many places in Europe: in Sweden, Denmark, Germany, Netherland, and

Austria. This system is a hybrid one where it works with other sources of energy to

supply heating and hot water to homes. In general it meets up to 60 % of heat demand

in such places. The system does not generate electricity.

It functions by having large colleting fields and store heat underground and

sometimes in caves or reservoirs. It is distributed “via collector circuit, using heat

1 Pros and Cons of Concentrated Solar Power. See https://youtu.be/8sLej0oD1Ak 2 A district heating system with solar energy storage - an energy efficient solution for the community. Got to https://youtu.be/8XAcYUvRbEQ

Figure 28 district solar heating

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transfer units in individual apartment, or centrally via circulating pipes.”1 Control and

safety systems help prevent over heat to occur in the summer. The heat temperature it

provides for water is 60 degrees Celsius which is 140 Fahrenheit, which is not at boiling

water, yet higher than the recommended safety standard in the US is 120. According to

Health Day, “Water at 140 degrees can lead to a serious burn within three seconds,”2

this shows how hot really this type of solar heating system can be produced.

Uses and Application of Photovoltaics Commercially.

The large PV power plant does not come in a number of types as the Solar Thermal ones

because the technology does not allow for a large space of creativity, in which it is just the regular

PV panels that are manufactured mainly of different types of silicon, monocrystalline silicon and

1 Solar Technology: The Earthscan Expert Guide to Using Solar Energy For Heating, Cooling and Electricity, See

Page 106. 2 Hot Tap Water May Pose Scalding Hazard, go to http://consumer.healthday.com/general-health-information-16/burn-health-news-87/hot-tap-water-may-pose-scalding-hazard-674893.html

Figure 29 The 550-megawatt Desert Sunlight solar project near

Joshua Tree National Park generates enough electricity to power

160,000 homes. It is the largest PV power plant. From usatoday.com.

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polycrystalline silicon. This system is simply similar to the domestic (residential) system, yet this

one is in a very large scale. What makes this system different than the domestic one is that it have

to take in account some major issues.1

The clearness index for the atmosphere;

Whether they track the path of the sun or not;

The diffuse and direct (beam) radiation amount;

The time of sunrise and sunset;

The angle of these relative to the modules.

The tracking system of the large PV power plant is concerned with issues that are related to the

movement of the sun resulting in an increase in the sunlight interaction with the panels. There are

three different directions the PV modules follow the sun with.

Vertical axis: is where the slightly tilted modules rotates vertically.

Inclined axis: where the modules are mounted on an axis that from an angle with

the ground and points in the north-south direction in a plane parallel to the axis of

rotation.

1 Solar Technology: The Earthscan Expert Guide to Using Solar Energy For Heating, Cooling and Electricity, See

Page 154.

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Two-axis trucker: the system can move the modules in the east-west direction and

tilt them at an angle from the ground, so that the modules always point at the sun.

There are indeed some commercial applications of the PV system that are other than the

one used in big plant. This type usually comes off grid and found in many places known as Stand-

Alone Photovoltaic. The most common commercially used ones are the telecom companies, in

which it provides power to repeater station, and mobile phone networks. The other type is the street

Figure 30 The Citi Bike docking station in Battery Park City that uses a standalone PV as shown

located at the right. By Thea Glassman/Tribeca Trib

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related one, used for street furniture, street lightning, signs, and many other applications in the

streets, such as the bike rental stations of New York

Construction of commercial solar power plants and Functional Aspects.

Solar plants are very much build as a large product on a national level or a one that

covers large areas of land. They are very expensive and involves corporate and government

contributions. In this paper the main focus will be on the Concentrated Solar Power System, and

the Photovoltaic one because the two systems are the most widely used systems commercially.

The Photovoltaic system does not need that much of an illustration because it only come in one

way of installation, which are illustrated in the uses section of this part. This system uses way

more land that CSP, it can be seen that the Topaz Solar Farm which is the largest PV station to

date uses an area of 19.06 km2, whereas the largest CSP the Ivanpah Solar Power Facility 14.16

km2.1

In many applications CSP is used in

very large areas, such as the Ivanpah Solar

Power Facility, which uses 173,500

heliostats with two mirrors hang on them

covering an area of 3,500 acers

(14.2km2).2 The Ivanpah one uses 3 towers

1 Project Finance. Go to http://www.firstsolar.com/en/technologies-and-capabilities/project-financing 2 Ivanpah Project Facts Go to http://www.ivanpahsolar.com/about

Figure 32 MWe Andasol plant in

Spain the storage system. From Solar

Millennium

Figure 31 The Ivanpah solar thermal power

system from Ivanpah Project Facts

ivanpahsolar.com/about

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with boilers inside. CSP uses highly reflective surfaces to concentrate the sunlight at a point

(tower) or a line (tube). These system has to have a storage system for its heat energy that

is stored in either liquid or soled, such as molten salt, ceramics, water, or concert, which is

then released at times where the sun is not shinning to keep the turbine.1 These thermal

storage systems increase the availability of the of heat energy from 1000 to 2500 hours. In

the 49.9 MW Andasol plant in Spain the storage is achieved with 28,500 tons of molten

nitrate and potassium salt storage, “that keeps it operational up to 7 and a half hours after

the sunset…”2 The outlet temperature of the storage system of this plant is between 290 C

(554 F) and 390 C (734 F), which is why this system is very successful in generating energy

around the clock especially in the summer.3 Regarding the CSP systems most of them

1 Solar Technology: The Earthscan Expert Guide to Using Solar Energy For Heating, Cooling and Electricity, See Page 190. 2 Solar Technology: The Earthscan Expert Guide to Using Solar Energy For Heating, Cooling and Electricity, See Page 190. 3 Solar Technology: The Earthscan Expert Guide to Using Solar Energy For Heating, Cooling and Electricity, See Page 190.

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include the following elements: concentrators, tracing system, a receiver, transport media

or storage, and power conversion.

There are mainly four type of commercial CSP systems, in which the concentrating

mirrors either focus on a line or a point.

a. Parabolic trough. This type is the

type where the history of solar energy

began with. It is very well illustrated

in the History part of the paper. The

parabolic trough collectors

concentrate the sunlight onto Dewar

tube containing fluid, such as

synthetic thermal oil, direct steam or

molten salt. This type tracks the sun in

one axis-east-west and are aligned north to south. The fluid can reach 300-550

C (572-1022 F) and is pumped through heat exchanges to produce very hot

steam. As mentioned in the beginning of this part the steam and in some systems

a combined steam and gas turbine generator is then spins the turbine and

generates electricity.1 The advantages of the system is that it is that it is

commercially available, commercially proven annual net plant efficiency of

14%, good land use factor, lowest material demand when compared to other

types, storage capacity, and the sun is concentrated at the tubes which are right

1 Solar Technology: The Earthscan Expert Guide to Using Solar Energy For Heating, Cooling and Electricity, See Page 191.

Figure 33 Parabolic trough

illustration from .nrel.gov/csp

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in front of the mirrors unlike the tower ones which the point of concentration

located at a very high tower burning birds that fly nearby. The size of the plant

is typically 50- 400 MW, with total power output capacity of 500MG1, and

about 500 GWh annual energy generation.

b. Linear Fresnel Reflector

(LFR). This system comes in

rows of flat or slightly concaved

long mirrors. The mirrors are

made on a Fresnel lens principal,

which is used in lighting where

the lenses concentrate the sunlight onto the central ,convex, long recover

located at a focal point which is filled with water that gets heated and turned

into steam at 200 -500 C (390-930 F). Its approach is very similar to the

parabolic trough because they are all in the same category. The size of the plant

is typically 50- 400 MW. The

advantages of the system is that

it is readily available, cheaper to make, very high space efficiency. Its main

disadvantage is that there have not been that much attention to it causing its

development to slow.1

1 Solar Technology: The Earthscan Expert Guide to Using Solar Energy For Heating, Cooling and Electricity, See Page 192.

Figure 34 Â Kimberlina Solar Thermal

Energy Plant, Bakersfield, California.

AREVA Solar

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c. Central Receiver or Solar Tower. The mirrors are pace in a circular matrix

which focus the sunlight at a point in a high tower. A heat-transfer substance,

such as water/steam molten salt or air is located in the point which generates a

superheated steam for a turbine at temperatures around or over 1000 C (1830

F). Gas can be used in the turbine instead of steam to take advantage of 60%

efficiency or more.1 The largest plant of this type is as mentioned earlier is the

Ivanpah Solar Power Facility with an Annual generation of 1,000 GW·h.2 the

advantages of this system are better potion for use non flat sites, good mid-term

prospect for high conversion efficiencies with an operating temperature beyond

1000 C (1830 F), and it can store high temperatures. Its main disadvantages are

that is needs a large area to be built on and might harm birds that fly over it due

to the heat and its shinny appeal similar to a desert mirage, in which one plant

killed over 500 brides over.3

d. Parabolic dish. This type is simply a dish that is concentrating the sunlight at

a point receiver. This point is similar to all the types has the same type of fluid

that can get supper heated to approximately 750 C (1380 F). This is used to

generate electricity in a small piston or Sterling engine, or a micro turbine

integral with the receiver. The dishes tracks the sun from one axis east-west.

The advantages of this system is that it has a very high conversion efficiencies,

modular (tracks the sun), most effectively integrate thermal storage and large

1 Solar Technology: The Earthscan Expert Guide to Using Solar Energy For Heating, Cooling and Electricity, See Page 193. 2 Ivanpah Project Facts, go to http://www.ivanpahsolar.com/about 3 California solar power plants ignite birds mid-flight go to http://www.cbsnews.com/videos/california-solar-power-plants-ignite-birds-mid-flight/

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plants, operational experience of first demonstration projects, easily

manufactured. Disadvantages of this type are that there are not that many

commercial examples, lower delivery potential for grid integration.

Figure 35 AN ARTIST’S rendering of a field of dish-Stirling

engine systems. from share.sandia.gov

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Figure 36 U.S. Solar Resource Maps showing national solar photovoltaics (PV)

resource potential and concentrating solar power (CSP) resource potential for

the United States.

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Cost Related Issues for Commercial Solar Plans.

Costs of large solar systems are very high and they usually be in hundreds of millions. To

illustrate on the cost issue an example of the two most recent and biggest projects in the US can

give a proper idea of cost related issue. These two big projects are the Ivanpah Solar Power

Facility, and the Topaz Solar Farm, which are compared briefly in the previous section.

The type of system the Ivanpah Solar Power Facility is CSP, where the Topaz Solar Farm

is a PV system. The Ivanpah plant is located in San Bernardino County, California with an area of

14.16 km2 the Topaz plant is located in Carrizo Plain, San Luis Obispo County,1 California with

an area of 19.02 km2.2 The total cost of the Ivanpha project was $2.2 billion with government loans

of $1.6 billion from the US Department of Energy, Google investment of $168 million and NRG

Solar, a subsidiary of NRG Energy invested $300 million in the project,3 while the Topaz project

cost about $2.4 billion paid by the owner MidAmerican Energy Holding Company (now known as

Berkshire Hathaway Energy).4 The DOE offered $1.9 billion in loans but the first developer First

Solar Inc. could not meet the offer deadline Sept. 30, 2011,5 yet the financing was possible due to

the MidAmerican the company that got an investment from billionaire Warren Buffett by the end

of that year the project was purchased.6

1 Ivanpah Project Facts go to http://www.ivanpahsolar.com/about 2 Topaz Solar Farm Overview. http://www.bherenewables.com/include/pdf/fact_sheet_topaz.pdf 3 DOE finalizes $1.6 billion Ivanpah solar loan. From Electric Power Daily or Go to http://archive.wusa9.com/news/local/story.aspx?storyid=146458 4 RECENT PROJECT FINANCING OVERVIEW. Go to http://www.firstsolar.com/en/technologies-and-capabilities/project-financing 5 TOPAZ SOLAR FARM WILL NOT MEET DOE LOAN GUARANTEE DEADLINE. Go to http://investor.firstsolar.com/releasedetail.cfm?ReleaseID=607518 6 Billionaire Buffett Bets on Solar Energy. Go to http://www.renewableenergyworld.com/rea/news/article/2011/12/billionaire-buffett-bets-on-solar-energy?cmpid=SolarNL-Thursday-December8-2011

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In terms of labor cost the two project are effected by the type of construction need because

it can be inferred from the type of system and the number of workers. The Ivanpah project had

2,100 constructions workers and reached 2,636, with 65 to 86 in maintenance and operation and

costing them 650 million in total employees’ wages, and earnings over the 30 years of operation.1

This high number of worker is due to the fact that plant has three towers, boilers, turbans, and

many other very large components along with the 347,000 mirror that are hanged on 173,500

heliostat, which each one of them can be a big project by itself involving builders, technicians,

Boilermakers, steel workers from all kind of fields, building the plant in about 5 years from 2010

to 2014.2 3 In the contrary, The Topaz construction project only lasted 4 years from November

2011 to November 2014, with a significantly large area compared to the Ivanpah project, it only

had 400 construction worker and up to 880 in the peak of the construction costing about $192

million.4 5 The low number of worker might be due to the fact that project is a PV one that does

not have the complication of boilers and turbines of a CSP system where it is just concerned with

the panels, its heliostats and the power storage system even though there were 9 PV Million Solar

Panels.6

There are many costs related to maintenance and other related issues that are very high in

costs and are hard to determine the actual price of. For instance the, “Ivanpah uses 32 million

gallons of groundwater each year to keep its boilers full and mirrors clean. In a desert, that’s not

1 Ivanpah Project Facts go to http://www.ivanpahsolar.com/about 2 Ivanpah: Cleaner Air. Jobs for California. Go to https://youtu.be/I00Au_S0joc 3 Ivanpah Project Facts go to http://www.ivanpahsolar.com/about 4 Topaz Turns On 9 Million Solar Panels. http://spectrum.ieee.org/energy/renewables/topaz-turns-on-9-million-solar-panels 5 Special report: How the rise of a mega solar panel farm shows us the future of energy. Go to https://gigaom.com/2015/01/20/a-special-report-the-rise-of-a-mega-solar-panel-farm-why-its-important/ 6 Topaz Turns On 9 Million Solar Panels. http://spectrum.ieee.org/energy/renewables/topaz-turns-on-9-million-solar-panels

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chump change.”1 Whereas the Topaz plant does not require washing, yet it uses water for

vegetation for dust control which is better because the water is not totally going to waste.

Outcomes of Large Solar Plant.

The same type of illustration can be made in benefits and outcomes of the solar plants using

the two mentioned plants. The Ivanpah project generates power of about 392 MW annually and an

Energy of 1 billion kWh annually,2 yet due to the system’s sensitivity to weather temperature the

system might generate far less of the amount advertised, according to an article written in

November 2014 in Forbs by Contributor James Conca, “Instead of a billion kWhs of electricity,

this year Ivanpah will produce less than 0.4 billion kWhrs, making its capacity factor only 12%,

not the 30% advertised. And certainly not the 90% of base load generators like nuclear power.”3

Whereas the PVsystem of the Topaz plant can generate power of 550 MW annually and it reached

an energy production of 1.05 kWhs.4 5 The Ivanpah project can serve 140,000 of an average

Californian home,6 while the Topaz plant can serve between 160,000 and 180,000 of the average

home in California.7 8 The Ivanpah project will generate about $350 million of tax revenues over

30 years,9 and the Topaz project will generate 16 million in tax revenue.

1 Thermal Solar Energy -- Some Technologies Really Are Dumb from Forbs. 2 Ivanpah Project Facts go to http://www.ivanpahsolar.com/about 3 Thermal Solar Energy -- Some Technologies Really Are Dumb from Forbs. Go to http://www.forbes.com/sites/jamesconca/2014/11/11/thermal-solar-energy-some-technologies-really-are-dumb/ 4 ELECTRICITY DATA BROWSER. Go to http://www.eia.gov/electricity/data/browser/#/plant/57695?freq=A&ctype=linechart&ltype=pin&maptype=0&pin=&linechart=ELEC.PLANT.GEN.57695-ALL-ALL.A&columnchart=ELEC.PLANT.GEN.57695-ALL-ALL.A 5 PROJECT OVERVIEW. Go to http://topazsolar.com/en/about-us/projects/topaz-solar-farm 6 Ivanpah Project Facts go to http://www.ivanpahsolar.com/about 7 Topaz Turns On 9 Million Solar Panels. Go to http://spectrum.ieee.org/energy/renewables/topaz-turns-on-9-million-solar-panels 8 PROJECT OVERVIEW. Go to http://topazsolar.com/en/about-us/projects/topaz-solar-farm 9 Ivanpah Project Facts go to http://www.ivanpahsolar.com/about

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Figure 37 Monthly energy production in MWhs for the three towers of the Ivanpah

Project for the US Energy Information Admenstration Electricity Data Browser

website. eia.gov/electricity/data/browser/

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Figure 38 Monthly energy production in MWhs for the Topaz Solar Farm

Project for the US Energy Information Admenstration Electricity Data

Browser website. eia.gov/electricity/data/browser/

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The illustration summary, and other cost and economic data.

Ivanpah Solar Power

Facility

Topaz Solar Farm

System CSP PV

Area 14.16 km2 (5.46 mi2) 19.02 km2 (7.34 mi2)

Location Ivanpah, San Bernardino

County, California

Carrizo Plain, San Luis

Obispo County, California

Cost Total cost of about $2.2

billion, Government loan $1.6

billion, Google with $168

million, NRG with $300

million.

A total cost of 2.4 paid by the

owner MidAmerican Energy

Holdings, due to Warren

Buffet investment.

(MidAmerican Energy

Holdings now Berkshire

Hathaway Energy)

Labor 2100 worker, and 2,636 in the

peak of construction.

400 worker and 880 in the

peak of construction.

Labor Cost $650 million over 30 years. $192 annually.

Maintenance and operation

cost.

$26.3 million annually.1 $3 to $4 million annually.2

Time taken to build the

project.

5 years form October 2010

till December 2014.

4 years from November 2011

till November 2014.

Size and annual power

generation.

392 MW. 550 MW.

Annual energy output 1 billion kWh. 1.05 billion kWh.

Average homes number it

can serve.

140,000 homes. 160,000 to 180,000 homes.3

Tax Revenue 350 million over 30 years. 16 million annually.

Tons of Co2 displaced

Annually.

13.5 million tons over 30

years.

377,000 tons annually.

Grid company/s dealing

with.

PG & E, Southern California

Edison.

Pacific Gas & Electric.

1 California’s New Solar Plant: Burning Up Taxpayer Money, Land, and Wildlife. Go to

https://www.aei.org/publication/californias-new-solar-plant-burning-up-taxpayer-money-land-and-wildlife/ 2 Topaz Solar Farm project datasheet. Download it at http://firstsolar.com/en/about-us/projects/topaz-solar-

farm/documents/topaz%20profile%20sheet?dl=1 3 Topaz Turns On 9 Million Solar Panels. Go to http://spectrum.ieee.org/energy/renewables/topaz-turns-on-9-million-solar-panels

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All the infomation of the table are from, Ivanpah Project Facts, and the Topaz Solar Farm

project over view, which are found at ivanpahsolar.com, and topazsolar.com, unless noted with

the end point.

These information regarding the cost related issues of the commercial solar energy for the

two major types of solar energy are meant to give a proper idea of the cost matters, not to compare

them in terms of which project is better. There are many factors that can make the any type better

than the other. Both projects had issues with the government funding as mentioned the deadline

issue of the Topaz and how the project was nearly save by Buffets investment, where the Ivanpah

is having issues with the loans they took from the DOE according to the mentioned Forbes article,

“However, after receiving a controversial tax-payer funded $1.6 billion loan under the U.S.

Department of Energy’s Loan Guarantee Program, Ivanpah investors, NRG Energy, Google and

BrightSource Energy, now want a $539 million federal grant to pay off their federal loan.”1

However, many opinions may support PV power plants, yet the panels of PV were, until recently

known to be very expensive compared to the mirrors of the CSP system. Therefore, it is very early

to judge which one is better, even though that the investments seem to be going in the direction of

PV, such as Warren Buffet’s one.2

This illustration of the major economic factors of the two project must give a proper idea

in regard to the major cost related topics. The illustration covered how government can assist, such

companies in the issues concerning the loans, and how privet investors can make a big difference

in financing the projects. Also the issue of the areas used, the time it took to build it, the total cost,

1 Thermal Solar Energy -- Some Technologies Really Are Dumb from Forbs. Go to http://www.forbes.com/sites/jamesconca/2014/11/11/thermal-solar-energy-some-technologies-really-are-dumb/ 2 California's Record-Breaking New Solar Plant Is Already Irrelevant. Go to http://www.businessinsider.com/ivanpah-solar-plant-already-irrelevant-2014-2

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and the labor costs, which are all the major factors of all solar project. The outcome of such project

is dealt with in the illustration in the topics of the number of homes it would serve, the power and

energy generated annually, the tax revenues, and the effect of nature on the systems, which are

similarly considered to be the major factors of a project, in fact as mentioned these are the factors

that determine if the project can be good or bad.

Conclusion.

In dealing with a highly technical, and highly debated issue such as solar energy it is hard

to come up with a come up with a proper conclusion to determine in which direction the next step

of the industry of solar energy is going to be. In the US and some other countries it might be very

hard to see a certain image of future. In general there are five major key players in the issue of

solar energy, and they are the owners whether individual or big corporate companies, investors,

the utility company, the government, and the technology. Those five play a large role in the future

of solar and as they interact together it makes it very difficult to come up with clear image of the

future of solar energy.

In many industries individual owners or end users find themselves governed by the major

service provider, or by government regulation, such as the car fuel, and public utility or service

providers. However, the solar energy industry has naturally given a great amount of power to the

end users by allowing them to produce their own power and either feed the grid and get money for

it, or store the energy.

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For example, Hawaii the state that its people use very low amount of energy and pay the

most with an average monthly consumption of 544 kWh and pay $203 monthly,1is now witnessing

a battle between most of the mentioned key players, yet as mentioned it seem as the end user might

win. In Hawaii utility companies are trying to slow the development of residential PV solar panels

by not approving the customers’ requests to install the panels and connect them to the grid, because

unlike many cold places net metering in Hawaii has become harmful to the grid companies.2 Due

to the loses the utility companies have when giving back amounts of money to customer who

generated excessive amounts of energy, and the infrastructure that cannot handle power going in

two directions, “In solar-rich areas of California and Arizona, as well as in Hawaii, all that solar-

generated electricity flowing out of houses and into a power grid designed to carry it in the other

direction has caused unanticipated voltage fluctuations that can overload circuits, burn lines and

lead to brownouts or blackouts.”3 In the case of Hawaii the state government did not stand still,

and pushed the utility companies to approve, “the lengthy backlog of solar applications”4 yet what

makes this case more appealing in terms of how the major five key player are present in it, is the

usage of batteries by the end users. Due to the complication of the issue of net metering, and

extremely high prices, according to the article of the New York Times by Diane Cardwell,

“Customers are increasingly asking about the batteries that he often puts in along with the solar

panels, allowing them to store the power they generate during the day for use at night. It is more

1 How Much Electricity Do You Use Each Month? Go to http://insideenergy.org/2014/05/22/using-energy-how-much-electricity-do-you-use-each-month/ 2 Solar Power Battle Puts Hawaii at Forefront of Worldwide Changes. Go to http://www.nytimes.com/2015/04/19/business/energy-environment/solar-power-battle-puts-hawaii-at-forefront-of-worldwide-changes.html 3 Solar Power Battle Puts Hawaii at Forefront of Worldwide Changes. See the video at the article page http://www.nytimes.com/2015/04/19/business/energy-environment/solar-power-battle-puts-hawaii-at-forefront-of-worldwide-changes.html 4 Solar Power Battle Puts Hawaii at Forefront of Worldwide Changes. See the video at the article page http://www.nytimes.com/2015/04/19/business/energy-environment/solar-power-battle-puts-hawaii-at-forefront-of-worldwide-changes.html

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expensive, but it breaks consumer reliance on the

utility’s network of power lines.”1 In which it

allowed the major solar power companies of

Hawaii to go in that direction and take the

customers completely of the grid.2 All this gives

an idea of how customers can effect the industry

to their benefit, even though Hawaii comes in a

sunny place as shown in the US solar map customer

can go of the grid in many places in the US.

Mentioning the issue of batteries

the market of batteries, which is the main

factor of why customers can go of the

grid and manage their energy

consumption with saving money, it

become necessary to go over the

development of the batteries and the new

intentions by Tesla to probably dominate

the market in the future. Elon Musk the CEO of Tesla Motors and Energy has lately introduced a

set of options of batteries, with mainly two residential types and a small commercial type for big

1 Solar Power Battle Puts Hawaii at Forefront of Worldwide Changes. See the video at the article page http://www.nytimes.com/2015/04/19/business/energy-environment/solar-power-battle-puts-hawaii-at-forefront-of-worldwide-changes.html 2 Solar Power Battle Puts Hawaii at Forefront of Worldwide Changes. See the video at the article page http://www.nytimes.com/2015/04/19/business/energy-environment/solar-power-battle-puts-hawaii-at-forefront-of-worldwide-changes.html

Figure 40 Elon Musk, CEO of Tesla Photograph by

Ringo H.W. Chiu — AP

Figure 39 Multiple batteries may be

installed together. From

teslamotors.com/powerwall

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buildings coming in 7 kWh for $3000 and 10 kWh sizes for $3500 called Powerwall and the

commercial one sold in 100 kWh called Powerpack costing about $25,000.1

The most appealing thing about the new batteries is that, they are by fare aesthetically

appealing and they are also the cheapest in the market for good batteries to assets a solar energy

system. The way these two types of home batteries can assists a solar energy system is that, “The

1 Elon Musk: Demand for Tesla's home battery is 'crazy off the hook' go to https://fortune.com/2015/05/06/elon-musk-tesla-home-battery/

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10 kWh home unit is designed as a source of backup power, while 7 kWh-unit can be used daily

to extend the environmental and cost benefits of solar after the sun has gone down.”1

To illustrate more in the issue of the government the Residential Renewable Energy Tax

Credit will end at December, 31 2016 which is a very close date for such project that might take a

long time to be done. However, Senators Richard Blumenthal (D-Conn.) along with some other

senators most of whom are democrats two independent and none republican including a

presidential candidate Bernie Sanders (I-Vt.), urged the Senate Committee on Finance to extend

1 Elon Musk: Demand for Tesla's home battery is 'crazy off the hook' go to https://fortune.com/2015/05/06/elon-musk-tesla-home-battery/

Figure 41 Tesla Powerwall Price vs Battery Storage Competitor Prices (Residential & Utility-

Scale) from Clean Technica

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the time of the tax credit in December 16, 2013, but their move did not work because the time is

still the same.1 2 This could give an indication that the residential solar energy upcoming will face

many challenges because the credit is very high and with 30% of the total cost of the system, which

means either buy now or suffer the system expenses. Luckily to the customers they may save 25%

with a limit of $5000 in New York State, which many other states can have a similar system.3

As mentioned in the cost part of large commercial solar plants many investors a hesitated

in regard to the issue of CSP, and preferring PV. According to David Crane, NRG’s chief,

responded when asked about another investment in CSP similar to the Ivanpah one they invested

in: “We’ve got $300 million invested in Ivanpah — let me see that work for a few months and

then we’ll decide whether we want to be involved in more.”4 “I don’t think that we’re going to see

large-scale solar thermal plants popping up, five at a time, every year in the U.S. in the long-term

— it’s just not the way it’s going to work,” said Matthew Feinstein, a senior analyst at Lux

Research a leader firm in providing strategic advice and ongoing intelligence on emerging

technologies, he also added talking about the CSP of Ivanpah in particular, “Companies that are

supplying these systems have questionable futures. There’s other prospects for renewables and for

solar that look a lot better than this particular solution.”5

1 Blumenthal wants extension of Renewable Energy Production Tax Credits for solar, fuel cell industries. http://www.nhregister.com/business/20150102/blumenthal-wants-extension-of-renewable-energy-production-tax-credits-for-solar-fuel-cell-industries 2 The proposal itself, http://action.sierraclub.org/site/DocServer/PTC_ITC_letter.pdf?docID=14702 3 Solar Energy System Equipment Credit NYS DTF. GO TO http://www.tax.ny.gov/pit/credits/solar_energy_system_equipment_credit.htm 4 A Huge Solar Plant Opens, Facing Doubts About Its Future. Go to http://www.nytimes.com/2014/02/14/business/energy-environment/a-big-solar-plant-opens-facing-doubts-about-its-future.html?smid=tw-share&_r=1 5 A Huge Solar Plant Opens, Facing Doubts About Its Future. Go to http://www.nytimes.com/2014/02/14/business/energy-environment/a-big-solar-plant-opens-facing-doubts-about-its-future.html?smid=tw-share&_r=1

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All these factors and the ones yet to come a very unstable due to the interest of the key

players over each other and how they are connected, makes it hard to see a clear image for solar

energy in the future. Even SolarCity with Musk as its chairman is refusing to use Tesla’s new

batteries due to preference for their customers to connect to the grid and benefit from net metering.1

Thus, for a relatively new industry it is very difficult to judge now of how the future may be

especially the there are many issues that are not really similar to most technological industries,

such as the issue of solar panels efficiency. According to Pure Energy, “These days the media

loves to hype emerging technologies, but the truth is we’re still using the same solar technology

we were back in the 1960’s. Since then, solar has become only moderately more efficient (unlike

computers or cellphones which experience dramatic improvements in short periods of time).”2 All

the signs, however, point that this time might be the best to join the market and benefit from the

tax credits and other major factors.

1 Tesla's New Battery Doesn't Work That Well With Solar. Go to http://www.bloomberg.com/news/articles/2015-05-06/tesla-s-new-battery-doesn-t-work-that-well-with-solar. 2 Solar Myths. Go to http://pureenergies.com/us/home-solar/solar-basics/solar-myths/

Attar, 62

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