The man-made greenhouse effect and the associated changes in our climate is already clearly evident. To avoid the worst impacts on nature and environment, it is necessary to reduce CO2 emissions as quickly as possible - and drastically. Likewise, it is useful to look at constantly rising energy costs and the finite nature of fossil fuels, for new, alternative energy sources.

One way to conserve the environment and our own wallets, the use of a mini-cogeneration plant, actually. A cogeneration heat and power plant (CHP) is a facility that produces both electricity and heat. It is centrally deployed at the location of heat consumption (as for example in the basement) of a home and works on the principle of combined heat and power. In it motor fuels are burned. This is for the generator to allow it to be driven and therefore provides the power supply.

This process heats the cooling water and hot gases are formed, which can be used for heating and hot water for one or more households, for example. Unnecessary heat can be temporarily stored in a storage tank for later use. The fuel that is suitable depends on what is used - vegetable oil, diesel or biodiesel, natural gas or biogas or wood pellets. If you generate more electricity than is needed, it is possible to feed this into the public grid.

What benefits arise from the use of a CHP? In any case, while benefiting the environment, by generating electricity locally, the resulting waste heat can be fully exploited. The decentralized power plants, however require a lot of energy to cool down the electricity generated in the hot exhaust gases. Input energy in a CHP plant has a much higher level of utilization, which makes a lot less pollutants released into the environment. CO2 emissions can be reduced by about half for the same amount of energy.

Another positive effect is that a cogeneration plant can be operated with renewable resources. In addition to the operation of a CHP worthwhile financially. It is independent of the flow of energy companies and their sometimes arcane pricing policy. It is also possible with this type of power of government incentives, the fuels are exempted from part of the fuel and therefore less expensive than fuel for the operation of a normal heating system. The sale of the excess current is next to a small source of income. A good way to produce energy at a good price!

With the possibility of oil running out in the not too distant future and the concern for the environment, biofuel research has increased and is focused on the use of biofuels as an alternative source of energy. Biofuels include the use of ethanol derived from plant material as well as derivatives from plants such as corn oil, vegetable oils and sugar cane. Ethanol is being used in a small way today, with approximately 2% of the world's fuel being ethanol based but the International Energy Agency calculates that this could rise to around 10% by the year 2025 and as much as 30% by 2050.

Biofuel research is continuing to find best ways to produce and use biofuels, but at the moment they are much less efficient than the gasoline we produce from oil. Gasoline produced from oil is around 75% efficient but bioethanol from corn, the usually plant source, is only around 20% efficient. Efficiency is a measure of how much energy is produced in relationship to how much is needed to produce the fuel. In the past only crops such as corn or sugar beet were used to produce ethanol for fuel but newer biofuel technologies are being developed to use cellulose, derived from grass or trees, as a plant source which is more efficient. Plant materials are fermented to produce the ethanol, in the same way as wine and other alcoholic drinks are made. Although it is possible to use ethanol alone as a fuel in automobiles it is usually used in a mixture with gasoline.

Biodiesel can also be produced from animal fats, vegetable oils and other fatty materials and is also used at present with diesel produced from oil. In this form it helps to reduce toxic emissions from diesel engines. In Europe the most common biofuel in use today is biodiesel. Bioethanol and biodiesel burn cleanly, they produce only carbon dioxide and water and none of the harmful particulates, hydrocarbons and carbon monoxide that cause environmental and health problems.

An alternative to bioethanol is called 'green gasoline' and can be made from trees and grasses in a process that will produce a fuel that is identical to the gasoline derived from oil. This is a very new technique first announced in 2008 by George Huber and his students Tushar Vispute and Torren Carlson of the University of Massachusetts-Amherst. It is a method that converts cellulose from plants directly into the components of gasoline. They also propose a method to make jet fuel in the same way, although the research for this is not so advanced. The methods proposed by this group could allow 'green gasoline' to be used significantly within ten or fifteen years. One advantage of this method over the use of bioethanol or biodiesel is that it can be used without any modifications to internal combustion engines or the jet engines of planes.

In theory 'green gasoline' can be produced with much less energy that bioethanol and will be cheaper to produce. It can also be produced from any cellulose containing plants such as wood chips, grasses and trees.

Although, in theory, the production and use of bioethanol or biodiesel seems like a good there are growing environmental concerns. According to the Marine Biological Laboratory changing the land use from pastures or food crops may increase the carbon emissions considerably so that pursuing an aggressive policy of replacing oil based fuels for biofuels may have a big impact on carbon dioxide production and hence on global warming. A further problem is that biofuel production need increased levels of nitrogenous fertilisers causing an increase in emissions of nitrous oxide which can have as big effect on the environment as increased levels of carbon dioxide have had. You can read more about this issue at Biofuel Production Increases Greenhouse Gases In Atmosphere. In addition the huge areas of land needed to grow plants for the production of biofuel lead to deforestation and an increase in carbon emissions.

So there are complex issues surrounding biofuel research and technology that need to be addressed before a major change in the way we fuel our vehicles, airplanes and factories should be made. Although it seems at first sight to be the best for the environment to switch to biofuels it may not be so good in the long run.

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