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Biofuelwatch has released a new report, ‘Sustainable Biomass: A Modern Myth’. It explores the certification companies certifying biomass as sustainable, the UK government’s proposed sustainability criteria for biomass, and developer’s ‘promises’ to source sustainable biomass.

What is U.S. electricity generation by energy source? In 2012, the United States generated about 4,054 billion kilowatthours of electricity.  About 68% of the electricity generated was from fossil fuel (coal, natural gas, and petroleum), with 37% attributed from coal. Energy sources and percent share of  total electricity generation in 2012 were:  Coal 37% Natural Gas 30% Nuclear 19% Hydropower 7% Other Renewable 5% Biomass 1.42% Geothermal 0.41% Solar 0.11% Wind 3.46% Petroleum 1% Other Gases < 1%

Somewhat surprisingly, the hot air that carries the heat from the earth at geothermal sites also contains carbon dioxide, CO2, the Greenhouse Gas that sends anti-technologists into a frenzy.  The suite of 20 geothermal sites from which Southern California Electric is obligated to buy electricity produces 730 tonnes of CO2 for every gigawatt-hour (GWh) of electricity produced.  Across the spectrum of all natural-gas power plants in the US, the average CO2 production is 519 tonnes per GWh.  That is, the geothermal power plants, which burn no fossil fuels whatsoever, produce 41% more CO2 than the run-of-the-mill natural gas power plant for the same amount of electrical energy produced.

Biodiesel can result in significant reductions in a number of air pollutants. In general, reductions are greater as more biodiesel is used, depending on the type of biodiesel (soybean, rapeseed or animal fats) and on the conventional diesel used in the blend.

Advantages of Tidal Energy1)  It is an inexhaustible source of energy. 2)  Tidal energy is environment friendly energy and doesn't produce greenhouse gases. 3)  As 71% of Earth’s surface is covered by water, there is scope to generate this energy on large scale. 4)  We can predict the rise and fall of tides as they follow cyclic fashion. 5) Efficiency of tidal power is far greater as compared to coal, solar or wind energy. Its efficiency is around 80%. 6)  Although cost of construction of tidal power is high but maintenance costs are relatively low. 7)  Tidal Energy doesn’t require any kind of fuel to run. 8)  The life of tidal energy power plant is very long. 9)  The energy density of tidal energy is relatively higher than other renewable energy sources.

Disadvantages of Tidal Energy 1)  Cost of construction of tidal power plant is high. 2)  There are very few ideal locations for construction of plant and they too are localized to coastal regions only. 3)  Intensity of sea waves is unpredictable and there can be damage to power generation units. 4)  Influences aquatic life adversely and can disrupt migration of fish. 5)  The actual generation is for a short period of time. The tides only happen twice a day so electricity can be produced only for that time. 6)  Frozen sea, low or weak tides, straight shorelines, low tidal rise or fall are some of the obstructions. 7)  This technology is still not cost effective and more technological advancements are required to make it commercially viable. 8)  Usually the places where tidal energy is produced are far away from the places where it is consumed. This transmission is expensive and difficult. Tidal Energy is thus a clean source of energy and doesn’t require much land or other resources as in harnessing energy from other sources. However, the energy generated is not much as high and low tides occur only twice a day and continuous energy production is not possible.

Ethanol is a grain alcohol that can be blended with gasoline and used in motor vehicles. Many gasoline stations provide a blended fuel, which typically is 10 percent ethanol and 90 percent gasoline.

Lost in the mix are the biofuels, fuels made from biological ingredients instead of fossil fuels. These starting ingredients can range from corn to soybeans to animal fat, depending on the type of fuel being made and the production method.

Biofuels and bioenergy are as old as civilization itself.  Solid biofuels like wood, dung and charcoal have been used ever since man discovered fire, and are still used today for cooking and heating in many communities in developing countries.

Ethanol, for instance, is an alcoholic biofuel easily distilled from sugary or starchy plants. It has been used to power cars since Ford’s Model T and, blended into conventional petrol, constitutes about 10% of the fuel burned by America’s vehicles today.

A 5,000-watt solar electric array on a roof that is 80% of an ideal site in terms of output, will generate about 4,800 kWh per year. Therefore, this solar energy will prevent 5,760 pounds of CO2 pollution from going into the atmosphere, every year.

If the trend continues for another 8-10 years, which seems increasingly likely, solar will be as cheap as coal with the added benefit of zero carbon emissions. If the cost continues to fall over the next 20 years, solar costs will be half that of coal.

When applied to electricity prices this predicts that solar generated electricity in the US will descend to a level of 12 cents (7 pence) per kilowatt hour by 2020, possibly even 2015 for the sunniest parts of America.