Презентация " Alternative energy"

Слайд 1

Alternative energy Alternative energy is any energy source that is an alternative to fossil fuel РАБОТУ ВЫПОЛНИЛ УЧАЩИЙСЯ 11 КЛАССА ГБОУ № 423 МАЛЫЙ ТАРАС

Слайд 2

Solar energy Solar energ y is the generation of electricity from the sun . It is split up into two types , thermal and electric energy . These two subgroups mean that they heat up homes and generate electricity respectively . Solar photovoltaics turn sunlight directly into electric current . The cells that make up solar panels are composed of semiconductor materials that are sandwiched together and specially treated so one layer has an excess of electrons , while the other has an excess of " holes " that electrons can occupy .

Слайд 3

Wind Power Wind energy is the generation of electricity from the wind . The most common kind of wind turbine has a horizontal axis and looks like a giant propeller , although some turbines have a vertical axis and look a little like eggbeaters . Small wind turbines provide up to 100 kilowatts , enough to sustain homes or store energy by recharging batteries ; these are sometimes used in remote off-the-grid locations .

Слайд 4

Hydroelectric and Tidal Power Driven by gravity , streams and rivers surge downhill toward the sea . Humans can take advantage of this natural process by blocking rivers with large concrete dams . Water builds up behind the dam and feeds into an intake ; the intake leads into a conduit that conducts the water through the dam to the other side . On its way through the conduit , the water turns a propeller-like turbine connected to a generator . Current from the electric generator feeds into the power grid and generate electicity .

Слайд 5

Biofuels Plants --- and some algae and bacteria --- already have a highly efficient system for storing solar energy . Through the complex process of photosynthesis , they use sunlight to synthesize organic compounds from carbon dioxide and water . By burning biomass --- organic material , such as plant matter or animal waste --- or the liquid fuels derived from it , some of the stored solar energy can be extracted and used to power businesses , homes and cars . The most common types of biofuels in use today are ethanol and biodiesel .