Climate Change Implications For US Energy Supply And Use - Climate Change and Energy Supply and Use - page 14

Table 3. Energy use through non-agricultural water use (public
systems)

Table 3. Energy use through non-agricultural water use (public
systems)

Location Findings Source

Nation No indings SAP 4.5

Nation Signiicant diversity in size and age of water supply and EPRI, 2002

treatment systems. National average reference case in 2050

shows about 112 kWh/capita, with surface water treatment

at 1,406 kWh /million gallons, groundwater supply at

1,824 kWh/million gallons.

Nation 955 kWh/million gallons for trickling ilter systems; EPRI, 2002

1,322 kWh/million gallons for activated sludge;

1,541 kWh/million gallons for advanced systems without

nitriication; 1,911 kWh/million gallons for advanced systems

with nitriication.

Nation For botled water, energy cost is water treatment is Gleick and

10-1600 kWhe/million liters, or about 0.0001 and Cooley, 2009

0.02 MJ(th) l −1 , Embodied energy in botled water is about

5.6 to 10.2 MJ(th) l −1 (Average energy cost for Southern

California municipal utilities is about 3000 kWhe/million

liters or 0.03 MJ(th) l−1)

National 7% of U.S. energy use is for providing water and waste Novotny, 2010

disposal. Treatment cost: varies from 0.24 kWh/m3 to

0.83 kWh/m3 , depending on size of plant and type of process.

Desalination requires 1.5 kWh/m3 to 15 kWh/ m3 depending

on whether the water is brackish or sea water.

In 2001, 19% of the California's overall electricity consumption (48 TWh) and 32% of
the state's total natural gas consumption (4.3 billion therms) was used to move and treat
water and wastewater. Of that, agricultural use was 10.6 TWh but only 18 million therms
(Klein, 2005). Costs may be exceptionally high in California, because so much water is
moved very long distances within the state.
The EPRI 2002 study could provide the basis for estimating energy impacts of
changes in irrigation demand due to climate change if the amount of water needed and
the source of the replacement water were known. EPRI 2002 has a comprehensive pic-
ture of U.S energy use for water supply, water treatment, and wastewater treatment for
the early 2000s period. Some of this data applies speciically to self-supplied water use