- Price per watt
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Price per watt, or $/W is a common way to compare the capital costs of various forms of electricity generation. It refers to the number of dollars one would have to spend to buy a machine capable of producing one watt of electricity. It is calculated by dividing the total project capital cost by the amount of peak power (watts-peak, or "Wp") it can produce.
Modern[when?] coal power plants are generally the least expensive sources of electricity by this measure, at around $2.10 a watt.[1] Large hydroelectric systems can be even less expensive by this measure; the Three Gorges Dam is reported to have cost ¥180 billion (US$26 billion), about $1 a watt, but actual costs are widely believed to be much higher.[2] Solar panels are currently selling for as low as just over $1 a watt in industrial quantities, but the "balance of system" costs put the systems closer to $4 to $5 a watt.[1] Large wind turbines are around $8 a watt and falling.[3] Natural gas-fired peaking power plants are around $6 a watt.[4]
Note that the capital costs are not the only determinant of the cost of the electricity produced. A coal plant needs to burn coal to produce power, while a solar panel has no fuel input at all. Maintenance, replacement, fuel costs and capacity factor all effect the cents per kilowatt hour of the power plant's delivered electricity.
References
- ^ a b John Markoff, "Start-Up Sells Solar Panels at Lower-Than-Usual Cost", New York Times, 18 December 2007
- ^ "Three Gorges dam wall completed", BBC News, 20 May 2006
- ^ Darrell Dodge, "The Future of Wind Power", The Illustrated History to Wind Power Development, 2006
- ^ "What Does Regular Electricity Cost?
Categories:- Electricity economics
- Energy stubs
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