This is the description I'm reading: In comparison to solar energy, the hydrocarbon fuel costs are significantly lower without rebates, tax benefits nor the cost of carbon emissions. A two–Kilowatt (KW) solar energy system costs about $45,000 and covers roughly half of a typical American household’s energy needs. At $45,000, a solar energy system equates to $9,000 a kilowatt. ....but I have no idea how they come up with 9,000 per kilowatt. Where does the $9,000 number come from? How is it calculuated?