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最近的突破有望減少海水淡化的成本，重要的是減少了所需的能源。例如，1998年，總部設於新加坡的AquaGen跨國公司宣佈，它開發出一種更便宜的、可輕易搬運式的淡化處理設備，可在任何地方迅速組裝。AquaGen跨國公司的總裁Gavin Liau 聲稱，設備的標準元件系統簡化了安裝程式。一個工廠生產100立方公尺水（2萬5千加侖）的成本卻不到30萬美元。Liau說，AquaGen 出售兩種海水淡化設備：一種使用蒸汽，而另一種使用電，從而產生去除鹽份所需要的能量。該公司表示，這兩類設備比目前使用的淡化設備節省了三倍多的能量。安裝這兩類海水淡化設備的工廠相對較小，每天最多生產5千立方公尺的飲用水，相較之下，中東的大工廠每天最多可以生產32萬7千立方公尺的飲用水。AquaGen正在進行大規模脫鹽水處理廠的可行性研究，這種工廠每天能處理4萬5千立方公尺水，希望在四年內投入運行。
以色列、巴勒斯坦、美國三國的科學家正在從事一項雄心壯志的海水淡化專案。根據參與該工程的一位科學家說，其目的是為了創造一個「淡水充足的新中東」。此專案的一個目標是建造太陽能的海水淡化機，可以安裝在卡車上，並且教村民們使用甚至製造這些機器。該專案也將研究鹽份和污染物是如何影響水質成分的。根據《世界水利環境工程》雜誌（1999年1月），1998年7月此專案啟動，並與美國能源部、美國環保署合作。一個更大的太陽能海水淡化設備正在測試之中。這個海水淡水系統完全自給自足，1999年早些時候，巴勒斯坦加沙的Al-Azhar大學和日本的Ebara公司對此系統進行了評估。這個系統每天最多能除去600公升鹹水中的鹽份。這個系統設計的時候是要用來灌溉的，而公司計劃亦同時發展小型的灌溉系統。儘管小型設備的優勢在於它輕便、安裝簡便，該公司也計劃要發展大型設備。由於大型設備沒有多少可拆卸的部分，所需要的維護便很少。
替代能源的新發展也可能推動海水淡化的發展。太陽熱能和燃料電池（兩者在此章節中都有描述）也可為海水淡化處理廠提供良好的能源。既然太陽能發展潛力很大的地方通常是最需要水的地方，將兩者聯繫起來就有很大的潛力。
備註：「我們耕種的方式是不去影響後代子孫的生存發展。多年來，我們的耕種系統已經得到了發展，非常適合我們的土地和社區的需要。放養家畜、種植農作物是農業生活不可分割的兩方面。在Tswana的語言裡，我們說：「家畜和農作物就好像丈夫和妻子。他們互相需要，在農場裏，他們也互相得益。」-- 1983年，南非的WESTERN TRANSYAAL社區聲明（來自「新土地」）
【文章連載】
■海水淡化 (上) (下)
版權歸屬 國際河網IRN，環境資訊協會（陶俊譯，李傑、李瑞玉 審校）
中英對照全文：http://e-info.org.tw/issue/water/2001/is-water-irn01101501.htm |
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There have also been recent breakthroughs that are expected to reduce the costs for desalination, primarily by cutting back how much energy is required. For example, in 1998 the Singapore-based company AquaGen International announced that it has developed a cheaper, portable water desalination plant that can be assembled anywhere quickly. AquaCen International chief Gavin Liau said the modular system of its plant makes installation easy. The unit can produce 100 cubic metres (25,000 gallons) of water for less than US$300,000. Liau said AquaGen sells two types of desalination plants - one that uses steam and the other with electricity to generate the heat needed to extract the salt. The company says that both types are up to three times more energy efficient than those now in use. The plants are relatively small, producing up to 5,000 cubic metres of drinking water per day compared to up to 327,000 cubic metres/day for the big plants in the Middle East. AquaGen is doing a feasibility study for a large-scale plant that can process 45,000 cubic metres and hoped would be operational in four years.
Israeli, Palestinian and US scientists are embarking on an ambitious desalination programme that is intended to create a "New Desalinized Middle East," according to one of the scientists working on the project. One of the programme's goals is to build solar-powered desalination machines that can fit on a truck, then teach villagers to use them and even make them. The programme will also look at how water is affected by salt and pollutants. According to World Water & Environmental Engineering (January 1999), it began work in July 1998, in conjunction with the US Department of Energy and US Environmental Protection Agency. A larger solar-powered desalination unit is undergoing testing now. The fully self-supporting desalination system was being evaluated in early 1999 by Al-Azhar University in Gaza, Palestine, and the Japanese company Ebara. The system can desalinate up to 600 litres of brackish water a day. The system is being designed with irrigation in mind, and the company plans to develop micro-inigation systems in parallel. The company also plans to develop larger-scale units, although the advantage of the smaller scale one is its portability and ease of installation. The units require little maintenance, as they have few moving parts.
New developments in alternative energy may prove to be a boost for desalination as well. Solar thermal power and fuel cells (both of which are described in this section) may provide good sources of power for desalination plants. Since places with good solar power potential are usually the places most in need of water, there is a huge potential to link the two.
"We try to farm in a way that we do not eat from our children's plates. Our farming systems have developed over many years to best suit our lands and our communities' needs. The keeping of cattle and ploughing of crops are two inseparable aspects of our farming. In the Tswana language we say "cattle and crops are like husband and wife. They need each other, they are mutally beneficial on the farm." -- STATEMENT BY WESTERN TRANSYAAL COMMUNITIES, SOUTH AFRICA, 1983 (FROM NEW GROUND)
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