It enables the construction to function as a self-managing ecosystem with less need for external energy.

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Google will obviously do quite well on these two: there are well known projects at the company to build renewable energy systems for external use just as there are similarly well known projects to power the company through renewables.

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Eigg for example has its own renewable energy system so there is no external power, and a number of islands, because of their very strong winds, have a very strong renewable energy programme which works for them economically as well as physically and ethically.

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Chinese oil companies already have interests in Niger, while Libya is looking for external partners as it opens up its energy sector to foreign investment.

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"Tepco (Tokyo Electric Power) should continue its efforts to improve the reliability of essential systems, to assess the structural integrity of site facilities and to enhance protection against external hazards, " the International Atomic Energy Agency (IAEA) said on Monday.

BBC: IAEA calls for improvements at Japan's Fukushima plant

For the cycle to run indefinitely and passionately, it must generate its own enthusiasm and energy, not be prodded by external motivators.

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Offshore energy production facilities are highly sensitive to external conditions and frequently have to stop operations when threatened by spills, storms or other unusual circumstances.

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The European energy market is strongly dependent on its external supplies.

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Meanwhile, solar energy costs would be competitive today with fossil fuels if all of the external costs of the latter were counted, such as the effects on air and water quality, and ultimately on human health, Orts points out.

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