There is an excellent website on the business of photovoltaics, SolarBuzz (http://www.solarbuzz.com/) which provides information on corporations, products, and people associated with the photovoltaic industry. On their home page they have a perpetually updated report on the price per kilowatt-hour (kWh) of photovoltaic electricity. Currently they show the price for photovoltaic electricity to be 21.7 cents per kWh.
If you compare this price to the cost of electricity from many conventional sources, especially coal, but even natural gas and oil burning power plants – even at today’s higher energy prices – at 21.6 cents per kWh, photovoltaic electricity isn’t even close. Coal generated electric power can be sold retail for $.04 per kWh, if not less.
As shown by the table in “Photovoltaics, the Ultimate Renewable,” however, it may be a fallacy to base kWh prices of photovoltaic electricity on the installation price. This is because the installation price might be compared to the externalities associated with other forms of electric power. What is the cost of transmission lines, which photovoltaics don’t need? What is the cost of actually building the coal mines, and the railroads, to serve coal-fired power plants? What is the cost to build a dam for hydroelectric power, or a facility to store nuclear waste?
The installation price of photovoltaics, similarly, is an externality. Moreover, the high initial installation cost is a sunk cost, not an ongoing cost like many externalities. Does anyone take into account the cost of building the entire drilling, shipping, storage and refining infrastructure for crude oil, when analysing the price of gasoline? These costs are long-ago amortized, and are no longer reflected in the price we pay at the pump. The economic problem with photovoltaics isn’t their ongoing replacement cost, which is minimal, it is the cost of building the entire photovoltaic infrastructure – the installed base – from scratch.
On a replacement basis, photovoltaic power is dirt cheap. Once you’ve installed a photovoltaic array, assume you replace 5% of the array each year. That would mean every twenty years the entire array would be replaced. Such a program would guarantee level electrical output forever. And what would the cost be in this scenario? Only 5% of installation costs, or less than one cent per kWh! That is why photovoltaic electricity is a compelling long-term investment, and the reason they are being purchased faster than manufacturers can make them.
Finally, look for production of photovoltaics to ramp up significantly in the next few years. As we discuss in “The Coming Boom in Photovoltaic Power,” the supply bottleneck of polysilicon raw material is about to be broken.