Comment Re:photovoltaics require silicon (Score 0) 835
They never named photovoltaics. They are talking about solar heat pump systems.
Photovoltaics are allmost allways forgotton because of the so-called low-return. While in germany big homeowners are making a killing selling energy back to the grid.
The fact that they did not compare photovoltaics tells me that this "research" might be biased.