Older reverse osmosis plants use about 5 kWh (1kWh = 3.6 x 106 J) to make 1 m3 of freshwater from seawater.
1) find the amount of energy in quads (1.05 x 1018 J) to supply the entire annual freshwater withdrawn by North America from seawater by the reverse osmosis process.
2) Newer more efficient plants use less than 2 kWh to make a cubic meter of water. Find the energy needed to supple all of Asia's freshwater using this process.
3) Comment on your results. How do these amounts of energy compare to other energy needs?
|
Agricultutal use
(%)
|
Industrial use (%)
|
Domestic use (%)
|
Percentage withdrawn of renewable resource
|
Per capita withdrawn
(m3/person/yr)
|
Total freshwater withdrawal
(km3/ yr)
|
Renewable water resource
(km3/ yr)
|
Regions
|
|
76
|
8
|
15
|
14.9
|
797
|
2,294.84
|
15,436.2
|
Asia
|
|
23
|
36
|
40
|
8.2
|
260
|
622.48
|
7,620.8
|
North America
|