Global Ecological Problems and Issues

One very simple way to produce biogas would be to have complexes of tanks filled with either freshwater or salt water, and to cultivate single-celled algae, seaweed or freshwater plants like water hyacinths in them. The tanks could be constructed either on coastal areas or in riverine environment, like Amazon and its tributaries. After the plants have consumed the nutrients in the water and filled the tanks, the tanks could be closed so that no more air gets in. In such conditions the anaerobic bacteria which do not require any oxygen break down the plant matter and produce gas that contains roughly 70 per cent of methane. After this the gas can be collected and the tanks can be opened again. The water can be stirred a bit so that the nutrients that have sank into the bottom will be mixed more evenly in the water, and a new crop of plants can be grown. In tropical conditions each production cycle would not take a very long time.

Various Southern and Northern countries could establish a complex of joint enterprises, international state-owned companies, to develop these various biogas technologies and to mass-produce them with cheap prices in order to make them more widely available for even middle and low-income households.

Some of the companies could concentrate on mass-producing cheap biogas producing equipment for individual households. Some of them could concentrate on the production of biogas-producing plants for large cities and smaller municipalities. They could also produce long series of equipment that is needed for collecting biogas from individual biogas-producing households or farms and equipment that is needed for purifying the raw biogas so that it can be used to fuel cars and buses. Raw biogas can provide cooking energy and lighting, but if the biogas is to be used by cars the impurities - carbon dioxide, carbon monoxide and sulfur - have to be removed.

Another interesting possibility would be an international, publicly-owned company mass-producing cheap Stirling engines. Stirling engine is a simple machine that can transform temperature differences into mechanical energy and further to electric power. First Stirling engines were invented already in 1839, but the technology has become truly attractive only recently, with the development of new materials that can tolerate higher temperatures and continuously changing temperature differences without breaking down relatively quickly.

Stirling engines can utilize any kind of heat source, from wood to solar energy. Solar electricity produced by Stirling engines is currently 10-12 times cheaper than the electricity produced by solar cells. The large-scale mass production of Stirling engines and parabolic reflectors that would heat them by sunlight would make solar electricity much cheaper than nuclear or coal power in the regions that receive large quantities of direct sunlight. Stirling engines can also produce cheap electricity by biogas, natural gas or by wood.

In England the first so called micro-CHP machines (CHP=combined heat and power) meant for individual households have already entered the markets. Even if they presently use the same fuel, fossil natural gas, than the larger plants they reduce the carbon dioxide emissions per household by more than one fifth by cutting the transmission losses in the power grid.

Third interesting area of cooperation could be the mass-production of vertical and horizontal windmills. Danish energy consultants have calculated, that it would be possible to mass-produce middle-sized, 150-300 kw windmills in Russia with approximately Euro 15 000 unit prize. Cutting the costs to this level might be possible because of the scale-benefits of mass-production and through the conversion of some of the unused production capacity of the Russian airplane factories to this purpose.

Another option is the mass-production of modern vertical-axis windmills. The first windmills were originally invented in Afghanistan and Iran during the 12th century. They were vertical-axis windmills that were mostly used for grinding the grain to flour. When the idea spread to Europe, Europeans changed the construction and shifted the axis into a horizontal position. After this the vertical windmill was, for centuries, known as the "Islamic" windmill and the horizontal windmill as the "European" windmill. In some European countries, most notably in Finland, the interest towards vertical windmills never really died, and the idea is about to make a big come-back.

Finnish companies have developed helix-shaped vertical windmills that are very efficient in collecting wind energy. They produce some electricity with very little wind and they can also utilize considerably higher wind velocities than the conventional windmills without breaking down. Above all, such vertical windmills are so silent and produce so little "visual pollution" that they could be erected, in very large numbers, on rooftops or on the sides of buildings, on top of poles, in electric pylons, on sides of mobile phone masts and even on the sides or tops of tall trees. This would enable millions of urban and rural households to produce much of their electricity by themselves, but the technology will be economically competitive only if such vertical windmills would be mass produced in relatively large numbers. Otherwise their unit costs will remain too high for most households.

Karl Yeager, president of the US Electric Power Research Institute, says that various kinds of small personal power stations using Stirling engines, windmills or other types of technologies could largely replace conventional centralised power stations by the mid-century. According to Yeager power grids will become more like the internet, networks for sharing electricity among millions of independent domestic and community generators.

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