This is a very simple question but something that I'm not able to wrap my head around. This Energy report states generated electricity. But what does "generated killowatthours" mean? I know that can't mean that the US produced that much electricity every hour...but what exactly does it mean?
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You are confusing kilowatt hours with kilowatts per hour (which is a fairly useless measure of anything).
A kilowatt is a measure of the rate at which energy is delivered (also known as power). One kilowatt means that 1000 joules of energy is being delivered every second.
A kilowatt hour is a measure of total energy delivered.
kilowatt = energy/time
kilowatt hour = kilowatt x time
= (energy/time) x time
= energy
So if your water heater draws 6 kilowatts when it is on, and is on for 30 minutes, then it has consumed 3 kilowatt hours.
According to the report:
In 2011, the United States generated about 4,106 billion kilowatthours of electricity. About 68% of the electricity generated was from fossil fuel (coal, natural gas, and petroleum), with 42% attributed from coal.
kilowatt hours = 4,106,000,000,000 kWh
hours = 356.25 days * 24 hours/day
= 8766 hours
kilowatts = (kilowatt hours) / hours
= 4,106,000,000,000 kWh / 8766 hours
= 468,400,639 kW
So we can see that during 2011, if you were to measure the power being generated in the USA, it would be about half a Terawatt.
answered Mar 15, 2013 at 22:21
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1\$\begingroup\$ The ONE valid use I have seen for kilowatts per hour is for a factory making e.g. solar cells : if it makes one panel per hour, and it can generate 1kw, their output is 1kw/hour! \$\endgroup\$– user16324Mar 16, 2013 at 14:45
Ws) you wouldn't need to ask Google to know that one kilowatt-hour is exactly 3600000 joule. \$\endgroup\$