SUBJECT : PHYSICS

TOPIC : green energy and energy conservation .

CLASS : 11TH

MADE BY : ASWIN KUMAR.R

TYPES OF ENERGY

RENEWABLE ENERGY:Renewable energy can be generated continuously practically without decay of source.Some examples are :• Solar energy , Wind energy , Geothermal energy , Hydro energy.

NON-RENEWABLE ENERGY:Non-renewable energy is energy that comes from the ground and is not replaced in a relatively short amount of time. e.g. energy generated from combustion of fossil fuels , coal , gas etc.

WHAT IS ENERGY ?

Energy lights our cities, powers our vehicles, and runs machinery in factories. It warms and cools our homes, cooks our food, plays our music, and gives us pictures on television. Energy is defined as the ability or the capacity to do work.

WHY TO CONSERVE IT ?

We have limited resources available on earth. Our demands are continuously increasing day by day. It is possible that someday most of the non-renewable resources will be exhausted and we will have to switch over to alternate energy

We save our money when we save energy.

We reduce pollution when we save energy.

We save our energy when we save energy.

WHAT WE CAN DO ?

RECYCLE -  compositing waste materials into new products to prevent waste of potentially useful materials. Turn off all electronic devices that are not in use. Not only turn them off but try to remember to unplug them. You will be surprised how much you will save with this simple step!  Replace old light bulbs with energy saving fluorescent bulbs. They may cost more, but will save you much more in the long run.

At Home•We should not keep lights unnecessarily switched on.• Reduce the energy your appliances consume by analyzing star ratings.• Improve your water heating efficiency to reduce energy costs.

At Public Places

• Switch of the fans and lights in the places like bus terminal and railway stations when not necessary.• Switch off the street lights.• Big Hoardings, lightened up for the whole evening and nights are other wastage of power which can be and should be avoided

HOW WILL IT HELP ?

Let’s Take an simple example :• let us assume electricity is available for Rs.4.00 per unit , a 100 watt bulb is used for 8 hrs a day then: •If we replace a 100 watt bulb with 22 watt CFL ,• The annual saving would be…• Power saved : 100W– W = 78W

GREEN ENERGY

Renewable energy is the energy from natural sources and minerals like sun, wind, and tides nuclear and hydroelectric power. The renewable energy is named so because it is environment friendly and it can replace non renewable energies like oil and coal

FORMS & TYPES OF RENEWABLE ENERGY

wind power   Wind has been an energy source for a very long

time.  It was used by the Chinese about 4000 years ago to pump water for their crops and by sailors to sail around the world.  The energy in wind can be used by making a tower which stands high above the sea level with a large propeller at the top.  What the wind does is it basically blows the propeller round and round which in turn helps produce electricity.  By building not just one but multiple of these towers you can produce more electricity at once.  The most suitable area to build these wind turbines would be in coastal areas, tops of hills, open fields or basically anywhere the winds are strong and continuous. 

ADVANTAGES AND DISADVANTAGES OF WIND POWER :

wind as we all know is free and can’t be purchased anywhere, therefore wind power is very cost efficient.  It produces no greenhouse gases or waste that could cause harm to the environment.

the land beneath the tower can still be used for farming since it doesn’t take up a lot of space. 

Last but not the least wind power is a very good way of providing energy to remote areas.  

these wind farms are usually near the coast, and near the coast means higher land prices.  Some people feel that these tall towers destroy the beauty of the land.

DISADVANTAGES Some other disadvantages of these wind

farms are they can affect television reception for people in close proximity to them, they can be noisy, they can kill birds, and lastly the wind cannot always be predicted.

HYDROPOWER Water is about 800 times denser than air and

therefore even a small stream of water can produce a reasonable amount of energy. Water energy can be in many different forms such as hydroelectric energy, micro hydro, hydro power without dams, and ocean energy.  Today there are many hydroelectric power stations in the world and together they are providing about 20% electricity across the globe. Solar energy is also one of the oldest renewable sources in the world.  This energy is taken from the sun in the form of solar radiation. . 

THE SOLAR POWER

Solar energy technologies use the sun's energy and light to provide heat, light, hot water, electricity, and even cooling, for homes, businesses, and industry.

There are basically three ways that we can use the sun’s energy. 

The first is by solar cells in which photovoltaic or photoelectric cells are used to convert light directly into electricity

The second is solar water heating in which the heat from the sun is used to warm the water in glass panels on the roof therefore no longer requiring gas or electricity to heat the water. 

The third is solar furnaces which use mirrors to capture the sun’s energy into a congested place to produce high temperatures. These solar furnaces can be used to cook food.

THERE ARE A VARIETY OF TECHNOLOGIES THAT HAVE BEEN DEVELOPED TO TAKE ADVANTAGE OF SOLAR ENERGY. THESE INCLUDE:

Photovoltaic Systems Producing electricity directly from sunlight. Solar Hot Water Heating water with solar energy. Solar Electricity Using the sun's heat to produce electricity. Passive Solar Heating and Day lighting Using solar energy to heat and light buildings. Solar Process Space Heating and Cooling Industrial and commercial uses of the sun's heat

WHY IS RENEWABLE ENERGY IMPORTANT?

Renewable energy is important because of the benefits it provides. The key benefits are:

Environmental Benefits Energy for our children's children Jobs and the Economy Energy Security

MADE BY : ASWIN KUMAR.RCLASS : 11TH