France is promoting via aggressive feed-in tariffs the expansion of solar photovoltaic. I believe this is quite a good thing even if our electricity is 90 percent low carbon. (80 percent nuclear and ten percent hydro)
Indeed, we will soon need additional capacity for both heat pumps and electric vehicles. However I believe the French (and other) government(s) should promote more aggressively solar water heaters.
Electricity is often generated by heating water. So using electricity to heat water is a very inefficient process. Using solar water heaters would enable us to change that.
Another advantage of solar thermal is that it is cheaper than solar photovoltaic and thus governments could add more renewable energy systems with the same amount of money.
My good friend Qat and his family will soon inhabit a beautiful and energy efficient building heated by both a solar water heater and a pellet burning heating system.
To their calculations they should heat their house by their ten square meters from September-October and from March to May. During the November – February, the wood-fired boiler would bring the majority of the needed heat.
Solar water heaters are needed. NOW. Only 50,000 of them are installed each year when 500,000 wood-fired systems are installed in France. Too me it is high time we install as much solar water heaters as wood-burning systems.
This way, France would count 15-20 million solar water heaters by 2050, thus using this energy source to the maximum of its potential. David JC MacKay believes this would be a good thing.
If ten square meters can heat for months an efficient house in Belgium, its potential in southern states and countries.
Israel understood quite early the importance of this relatively simple technology. Indeed, 90 percent of Israeli households have solar water heaters.
It is high time many countries change their policies on solar thermal and enable this efficient, relatively cheap and renewable energy source to reach mass markets.