标题: A Desalination Plant at Carlsbad, Calif Under Construction [打印本页] 作者: choi 时间: 3-3-2013 13:55 标题: A Desalination Plant at Carlsbad, Calif Under Construction Felicity Barringer, In California, What Price Water? As costly desalination plant might become a bargain. New York Times, Mar 1, 2013. http://www.nytimes.com/2013/03/0 ... -affordability.html
Quote:
"in three years * * * the newest and largest seawater desalination plant in the Western Hemisphere.
"The San Diego County Water Authority has agreed to buy at least 48,000 acre-feet of water from the plant each year for about $2,000 an acre-foot. An acre-foot equals about 326,000 gallons, roughly enough for two families of four for a year. * * * The price of water the authority now gets from the Metropolitan Water District of Southern California is about $1,000 an acre-foot.
"The technology used in the Carlsbad plant, known as reverse osmosis, was developed decades ago. It involves pushing the water through a series of microscopic sieves rolled up into larger cylindrical filters. The energy-intensive process separates pure water from both salt molecules and impurities. The filters, some of which are made locally, are cheaper and more durable than they were a decade ago, industry accounts say, bringing down the overall price of the plant and its operations.
"The environmental group the Surfrider Foundation, which has fought the Carlsbad plant at every turn, expects the plant to be an object lesson in how not to guard against water shortages. Among other things, the foundation emphasizes the energy needs of the plant, which will consume 5,000 kilowatt-hours of electricity to produce an acre-foot of water.
Note:
(a) Carlsbad, California http://en.wikipedia.org/wiki/Carlsbad,_California
(an affluent coastal resort city in San Diego County; In the 1880s a former sailor named John Frazier dug a well in the area Agua Hedionda Lagoon and began selling water; named after the Bohemian [spa] town of Karlsbad [Czech: Karlovy Vary; German: Karlsbad; English: Carlsbad; named after King of Bohemia and Holy Roman Emperor Charles IV, who founded the city in 1370])
* pestilent (adj):
"1: destructive of life : DEADLY
* * *
4: INFECTIOUS, CONTAGIOUS <a pestilent disease>" http://www.merriam-webster.com/dictionary/pestilent
(c) Metropolitan Water District of Southern California http://en.wikipedia.org/wiki/Met ... Southern_California
(the largest supplier of treated water in the US; a cooperative of 14 cities and 12 municipal water districts that indirectly provides water to 18 million people; created by an act of the California Legislature in 1928; water sources: State Water Project and Colorado River Aqueduct)
The last clause explains what the NYT says, "Water supplied by the Southern California water district comes from Northern California transfers and Colorado River diversions."
(d) desalination http://en.wikipedia.org/wiki/Desalination
("In Israel as of 2005, desalinating water costs US$ 0.53 per cubic meter. As of 2006, Singapore was desalinating water for US$ 0.49 per cubic meter"; The [Tampa, Florida] plant can now produce up to (25 million US gallons (95,000 m3)per day when needed)
(e) There are basically two methods of desalination: thermal (distillation) and reverse osmosis. Tampa Bay and Singapore use reverse osmosis. whereas Tianjin, thermal (its nuclear power plany supplying the waster heat). See
Tianjin, China (MED EPC Plant). IDE Technologies, Ltd (Israel), undated http://www.ide-tech.com/projects/tianjin-china-med-epc-plant-1
("China's largest thermal desalination plant"; EPC (Engineering, Procurement, Construction); MED (Multi-Effect Distillation))
(f) 1 gallon= 4 liters (3.79 liters to be exact)
CURRENTLY San Diego pays $1,000 an acre-foot (= 326,000 gallons= 1,233 m3= 1,233,000 liters)--about $0.90/m3. San Diego is committed to paying double for water output of Carlabad plant.
(g) Compare
Desalination | Costly Drops; Removing salt from seawater might help slake some of northern China’s thirst, but it comes at a high price. Economist, Feb 9, 2013 http://www.economist.com/news/ch ... hirst-it-comes-high
("A cubic metre of water from the [Tianjin's Beijiang] plant costs about 8 yuan ($1.30) to produce—slightly more than the price paid by industrial users, but 60% higher than the tariff for households. Mr Tan [Peidong, a deputy general manager of the Beijiang facility,] says a cubic metre of Yangzi-basin water will cost about 10 yuan")
* I introduced this Economist article at the time, so there is no need to read again.