The best-known of these tools is probably the hand-held window squeegee, used to remove the cleaning fluid or water from a glass surface. A soapy solution acts as a lubricant and breaks up the dirt, then the squeegee is used to draw the now water-borne dirt off the glass leaving a perfectly clean surface.
Another way of estimating the cost of electricity would be the cost of an ordinary solar system, or $21,000 as shown in the example above. So the cost of a Tesla retrofit system would be in the range of $33,000 to $37,500.
We assume that as the national market for solar grows, regional variation in prices will become insignificant. Based on these assumptions, the levelized cost of solar today â without any incentives â varies from around $0.19 per kilowatt-hour (kWh) in Los Angeles to $0.29 per kWh in Seattle.For more discussion on the cost of solar, see the Appendix or for some context, see the Sensitivity Analysis.he cost of the tax credit will reach $22 billion a year by 2016 and the tax credit isnât the only subsidy. The federal government estimates that accelerated depreciation for solar and geothermal projects costs about $300 million per year, forecast to rise to $7 billion by 2016.