Are Desalination Technologies the Answer to the World Water Crisis?
Investors and policy makers are increasingly advocating desalination technologies that use seawater to make freshwater. As reviewed in an EcoSeed Special Report, the interest in desalination technologies is growing due to the fact that there is insufficient fresh water to meet the daily drinking and sanitation needs of all those inhabiting the planet.
Desalination involves the process of removing salt from sea or brackish water to produce drinkable water. According to the International Desalination Association, there are over 13,000 desalination plants worldwide producing more than 12 billion gallons of water a day. Although this may seem like a lot, this represents only 0.2 percent of global water consumption.
A report by Lux Research indicates that to meet the demands of a growing human population, worldwide desalinated water supply must triple by 2020. This report indicates that desalination is feasible, as the global water desalination market is expected to expand at a compound annual growth rate of 9.5 percent over the next 10 years.
While desalination is garnering considerable interest, it is not price competitive with traditional water sources. The construction, operation and maintenance costs make desalination at least three times as expensive as traditional sources.
Some argue that reverse osmosis (a method of passing saltwater through a membrane filter at high pressure) may be less expensive than distillation methods commonly used. The American Membrane Technology Association estimated that existing traditional water supplies cost 90 cents to $2.50 per 1,000 gallons produced. Brackish desalination technologies range from $1.50 to $3 for the same amount of water, and seawater desalination costs from $3 to as much as $8 per 1,000 gallons.