ENERGY

To be or not to be sustainable?

AESc 210: GlobalizationSpring 2018

OUR AGENDA

•Physical concepts of energy•Renewable and non-renewable

energy types• Issues with non-renewables• Issues with renewables•What’s next?

PHYSICAL CONCEPTS of ENERGY

• It’s an abstract entity and comes in many forms.

• Best understood by its properties.• We usually think of energy in terms of the

“work” it can do (for us).• Transforming energy from one form to

another (more useful) form is a major engineering activity.

SOME COMMON FORMS of ENERGY

•Mechanical: kinetic and potential– solids, liquids, gases

•Electrical: magnetic, electrical– inductors, capacitors

•Thermal: internal energy– your body temperature is a measure

•Nuclear: atomic fission,fusion•Chemical: reaction types

SOME PROPERTIES of ENERGY

•The law of conservation of energy– states that the total energy of an isolated system

is constant;– energy can be transformed from one form to

another, but cannot be created or destroyed.

•Systems tend toward uniformity– Left to themselves, systems tend toward

uniformity of temperature, pressure, and density.

•Energy conversion processes are irreversible– Some of the input energy is not converted to the

desired output energy form. Usually it is lost in the form of heat.

SOME ENERGY CONVERSION PROCESSES

•Coal -> electricity•Water at height -> electricity•Gasoline -> motion•Wind -> electricity•Electricity -> light•Electricity -> motion•Electricity -> heat

Some ENERGY sources

• Biomass• Coal• Geothermal energy• Hydropower• Natural Gas• Nuclear energy• Oil• Solar energy• Tidal energy• Wind energy

RENEWABLE, NON-RENEWABLE ENERGY

• Biomass• Coal• Geothermal energy• Hydropower• Natural Gas• Nuclear energy• Oil (petroleum)• Solar energy• Tidal energy• Wind energy

Some pros and cons of NON-RENEWABLE ENERGY TYPES

•Biomass•Coal•Natural gas•Oil (petroleum)

PETROLEUM RESERVES

Hubbert’s Peak (1956)

Peak oil depletion scenarios graph which depicts cumulative published depletion studies by ASPO and other depletion analysts.

The Economist, May 15, 2012An unconventional bonanzao Natural gas is a flexible fuel, capable of

heating homes, fueling industrial boilers and providing feedstock for the petrochemicals industry, where it is turned into plastics, fertilizer and other chemicals. It is a portable fuel for transportation.

o Shale has rapidly transformed America’s energy outlook. Discoveries of vast reserves of conventional gas from traditional wells have pushed up known reserves around the world.

o Global reserves have been steadily increasing for at least 30 years.

o 2014 - shale and other unconventional as well as new conventional gas finds have increased reserves to 200 years or more.

o Biggest advances have been in power generation, the combined-cycle gas turbine, makes it cheaper to generate electricity from gas, but the process releases up to 50% less carbon dioxide than does coal.

NATURAL GAS

Climate Changeover the Past Millennium

Some political-economic aspects of fossil fuels

• Coal in US: big investment in current mining and transportation setup; fewer workers.

• Oil: major political issues in the middle east, where huge amounts of high quality oil are produced by OPEC.

• Natural gas: fracking of shale deposits.

• Subsidies in the form of write-offs keeps prices “low”.

Some political and economic aspects of biomass-based fuels

• Ethanol: uses corn as the biomass source.

• Redirects corn from food uses and thus drives up food prices. Hardest on poorest segment.

• Benefits mid-west corn growers big time.

• If switch-grass could be used cost-effectively it would make some sense.

• Managed forests have some potential.

Some pros and cons of RENEWABLE ENERGY TYPES

• Bioenergy

• Geothermal energy

• Hydropower

• Nuclear energy

• Solar energy

• Wind energy

Winds are not very predictable although there are areas where winds are relatively constant and intense.

Gaining in popularity because of the low ecological impact.

WIND ENERGY

First generation biofuels are made from sugar, starch, vegetable oil, or animal fats using conventional technology.

Second generation biofuels are made from non-food crops, e.g., cellulose.

Third generation biofuels are made from algae. Algae is a low-input, high-yield feedstock to produce biofuels. It produces 30 times more energy per acre than land crops such as soybeans.

ENERGY from BIOMASS

GEOTHERMALU.S. has the greatest geothermal energy production

The earth is a virtually infinite heat source.

Temperature is constant, predictable as f(temp).

Water is an abundant working fluid to transport energy.

Access varies with geography and location.

HYDROELECTRIC ENERGY

Huge capital investment, ecological changes in local area, limited by sources of water.

The most common method today is nuclear fission.

All utility-scale reactors heat water to produce steam, which is then converted into mechanical work for the purpose of generating electricity or propulsion.

The Nuclear Fuel Cycle. Uranium is mined, enriched, and manufactured into nuclear fuel, (1) which is delivered to a nuclear power plant. The spent fuel is delivered to a reprocessing plant (2) or to a final repository (3) for geological disposition. In reprocessing 95% of spent fuel can be recycled to usage in a power plant (4).

NUCLEAR ENERGY

Proven track record, large capital investment, complex infrastructure, security concerns.

SOLAR ENERGYSolar radiation along with secondary solar resources such as wind and wave power, hydroelectricity and biomass account for 99.97% of the available renewable energy.

There is more energy absorbed in one hour of sunlight than the world used in one year.

SOLAR AVAILABILITY

Solar power systems covering the areas defined by the dark disks could provide more than the world's total primary energy demand in 2006 (assuming a conversion efficiency of 8%).

The colors in the map show the local solar irradiance averaged over three years from 1991 to 1993 (24 hours a day) taking into account the cloud coverage.

U.S. POWER PRODUCTION MAP

Power is generated close to population centers now.

Biomass Resource Map: US

Geothermal Resource Map: US

Solar Resource Map: US

Wind Resource Map: US

Solar vs Ethanol

Federal budget:

Solar <$100M

Ethanol $2B (subsidy)

Area devoted to ethanol (corn):125,000 sq mi

If that area were devoted to solar, we could satisfy the total electricity needs of the USA!

PRIMARY ENERGY SOURCESAlternatives to Petroleum?

•Conservation / Efficiency--not enough•Hydroelectric --not enough•Biomass--not enough•Wind--not enough •Wave & Tide--not enough

•Natural Gas –fracking?, sequestration?, cost?•Gas Hydrates--sequestration?, cost?•Clean Coal --sequestration?, cost?

•Nuclear Fission --radioactive waste?, terrorism?, cost?•Nuclear Fusion --too difficult?, cost?•Geothermal HDR--cost ? , enough?•Solar terrestrial --cost ?

PRIMARY ENERGY SOURCESAlternatives to Coal and Petroleum?

Conservation and efficiency increases:not enough

Biomass: not enough Geothermal: not enough Tidal: not enough Wind: not enough

Solar: cost and political pushback

PRIMARY ENERGY SOURCESAlternatives to Petroleum?

Natural gas: fracking, sequestration, cost

Clean coal: sequestration, cost

Nuclear fission: radioactive waste, terrorism, cost

Energy-Engineering Challenges Photovoltaics --drop cost by 100 fold.Photocatalytic reduction of CO2 to methanol. Direct photoconversion of light + water to produce H2.Thermochemical processes with catalysts to generate H2 from water that

work efficiently at temperatures lower than 900 C. Fuel cells --drop the cost by 10-100x + low temp start.Batteries and supercapacitors--improve by 10-100x for automotive and

distributed generation applications.H2 storage --light weight materials for pressure tanks and LH2 vessels, and/or

a new light weight, easily reversible hydrogen chemisorption systemPower cables (superconductors, or quantum conductors) to rewire the

electrical transmission grid, and enable worldwide electrical energy transport; and also to replace aluminum and copper wires essentially everywhere --particularly in the windings of electric motors and generators

LED lighting to replace incandescent and fluorescent lightsSuper hard and tough coatings that will enable vastly lower cost of deep

drilling, to enable HDR (hot dry rock) geothermal heat mining.Lubricants to reduce friction more effectivelyThermoelectric materials to capture waste heatCO2 mineralization schemes that can work on a vast scale, hopefully starting

from basalt and having no waste streams.

SUMMARY

• The changing global environment demands more

energy. More people, higher living aspirations.

• “Do MORE with LESS!” Efficiency gains will be made.

• Affordable renewable energy is the key to a

successful future. Major competition for limited

energy could lead to disaster.

• Politics and engineering are keys to transitioning

successfully to renewable, sustainable energy.

THE RAW POWER OF NATURE

Thomas Edison

“I'd put my moneyon the sun and solar energy. What a source of power! I hope we don't have to wait 'til oil and coal run out before we tackle that.”

(1847-1931)

www.ThomasEdison.com