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小規模的水力發電
在某些地區，小規模的水力發電可能是最適用的能源型態。如果細心地加以規劃與執行，則小型水壩（發電量10MW以下）對環境和周邊社區造成的損害比大型水壩來的少。小型工程還可以為地方經濟提供更好的助益，幫助發展當地的技能，開發當地的資源。然而，僅賴規模大小一個因子，還不能決定一個工程是否會對社會或環境造成傷害；正如對任何水力發電工程進行規劃一樣，小型水壩也應該進行單獨評估，瞭解它們對集水流域和社區的影響，評判它們是否適合整個集水流域管理規劃。（請見資料來源《Beyond Big dams》，國際河網IRN有關適當開發水力發電的報告。）
地 熱
地熱能源直接來自地心，與火山爆發、地震的能量來源相同。在某些地方，埋藏在地表下面的天然「熱能儲藏庫」能夠提供大量的地熱能。1993年，這種天然的（地熱）蒸氣能源占肯亞能源供應的9%，占尼加拉瓜能源供應的28%，占菲律賓的26%；這裏所列舉出的，只是所有正利用其地熱儲藏庫的國家當中的少數幾個。
然而，發展任何小規模的地熱能量利用，並一定不需要「地熱儲藏庫」。地球上任何地方都可以採用地熱熱泵技術，所利用的是地表下不變的溫度。在冬季，可以利用熱泵技術從地底下抽取熱量，為建築物供暖；在夏天，又可以引導散熱，達到降溫作用。土壤表面至其下數英呎處之間的溫度隨季節變化，但是再往下深入的地層溫度就是終年固定的。在過去的數年中，這項技術已經取得重大進展；與初期的設計相比，其安裝成本已下降了30%。
版權歸屬 國際河網IRN，環境資訊協會（陶俊 譯，吳國玢、李瑞玉 審校）
中英對照全文：http://e-info.org.tw/issue/water/2001/is-water-irn01112601.htm |
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Small-scale Hydropower
In some areas, small-scale hydropower schemes may be the most appropriate energy source. When carefully planned and implemented, small dams (under 10 megawatts) can be less harmful to the environment and surrounding communities than large dams. Small projects can also better serve the local economy, and help develop local skills and resources. However, scale alone does not determine whether a project will be socially or environmentally harmful. As with planning any hydropower project, small darns should be evaluated individually for their impacts on the catchment and communities, and for their fit in an overall catchment management plan. (See Resources for Beyond Big Dams, an IRN report on appropriate hydropower development.)
Geothermal
Geothermal energy is derived from the earth's core. It is the same source from which volcanoes and earthquakes get their energy. In some places, natural hot "reservoirs" below the surface of the earth provide large-scale sources of geothermal power. In 1993, these natural steam sources accounted for 9 percent of Kenya's energy supply, 28 percent of Nicaragua's power and 26 percent of the Philippines, to name a few nations that are making use of their geothermal reserves.
Geothermal reserves are not needed to take advantage of geothermal power on a small scale, however. Any place on earth can take advantage of geothermal heat-pump technology, which capitalizes on the stable temperature below the earth's surface. This uses heat-pump technology to extract heat from the earth in winter for heating buildings and to dissipate heat in summer for cooling. While the temperature of the soil to several feet below the surface varies with the seasons, below that depth the earth's temperature stays about the same year-round. This technology has made significant advances in the past few years. Installation costs have been reduced by 30 percent compared to earlier designs.
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