"kwh" is correct and usable in written English.
It is an abbreviation for "kilowatt hour," a unit of energy, and is usually used when discussing energy consumption or production. For example, you might write, "My annual electricity bill is 2,000 kwh."
A study by the Boston Consulting Group projected that prices would need to come down to $200 or less per kWh to make electric vehicles truly competitive with the more familiar car that relies on internal combustion.
In theory, this is enough to produce some 740 billion kilowatt hours (kWh) of electricity a year more than double the 319 billion kWh that ERCOT's customers actually demanded during 2010.
Solar or wave power cost at least 18 or 20 cents per kWh.
That is equivalent to 20% of America's existing electricity-generation capacity: not a bad start.Robert Fishman, the boss of Ausra, an Australian-American company based in Palo Alto, California, reckons that his firm's Fresnel arrays combined with its proprietary heat-storage system can produce electricity for 8 cents a kWh.
It also spends over $1 per kWh on electric power (ten times the domestic civilian price) in battle zones, because electricity must often be provided using generators that run on fossil fuels.If some of this fuel could be replaced by power beamed down from space, it could cut costs and reduce the need for complex and vulnerable supply lines, the NSSO report argues.
Applying this methodology to the real world, your correspondent reckons that recharging a Honda Fit EV's 20 kWh battery pack from scratch in the early hours of the morning produces 16.6 pounds of carbon dioxide west of the Rockies, 21.8 lb in Texas, and 50.6 lb in the upper Midwest.
But as Dr Salter and his team improved their design, they managed to bring the cost-per-kWh down to the cost of nuclear power.
The first big municipal seawater plant, which began operating in Jeddah, Saudi Arabia, in 1980, required more than 8 kilowatt hours (kWh) to produce one cubic metre of drinking water.The energy consumption of such plants has since fallen dramatically, thanks in large part to energy-recovery devices.
That would make EGS economic only in places with strong financial incentives, such as Germany, where operators of renewable-energy projects receive generous subsidies in the form of feed-in tariffs currently $0.31/kWh for power from EGS.Technological improvements, such as cheaper and better methods for drilling, creating reservoirs and improving water-flow rates, could cut the cost of EGS.
Dr Wyborn estimates that electricity from EGS could initially cost an additional $0.09/kWh over conventional geothermal, or about $0.19/kWh.
Even more established renewable sources such as wind (€0.07/kWh) and biomass (€0.08/kWh) produce electricity that costs more than that derived from coal (€0.05/kWh with coal at $60 per tonne) or gas (€0.06/kWh with oil at $55 a barrel).
