I saw this in the newspaper today, that the world’s largest photovoltaic solar farm has been funded for construction in Lopburi, Thailand, which is about an hour from where I live. I thought, really? Will this really be the largest such installation? At 73 megawatts it is pretty big for sure.
Given the continued high price of solar cells this seems like a terrible waste of money. The developer is Natural Energy Development and according to the story they will enjoy an adder of eight baht per unit of electricity for 10 years. That is an adder of 8 baht per kilowatt-hour where a kilo-watt hour currently costs around 2.75 baht. So that illustrates what kind of ridiculous subsidies are still required for PV installations to be profitable.
I thought of the technology I was working on a couple years ago when I did a short stint at a company in Bangkok. They had purchased the license to manufacture the Stirling Energy Systems solar thermal electricity generator. It is a system based on a parabolic dish reflector and Stirling heat engine. The system was compelling because it utilized the same technologies used in automobiles – bent metal and glass, an engine much simpler than an internal combustion engine, and very simple electronics for tracking the sun and pointing the dish. Each unit produced 25 kilowatts and in volume production should cost about US$25,000, right there at the cost per watt of fossil fuel produced electricity without any of the externalities.
Sadly, that Bangkok company seems to have been unable to make any progress, although Stirling Energy Systems did land some massive contracts for solar farms in the U.S. So instead of something much more cost effective, Thailand is spending five billion baht on a PV farm. Of course there is one potential technical issue with any solar energy system in Thailand, which is that just about everywhere in the country there are many cloudy days, quite unlike the deserts of southwestern U.S. Concentrating solar power systems are particularly poor performers when the skies are overcast since they utilize only direct normal insolation and cannot make use of scattered light which PV can.