Is it worth it?

Energy revolution with the help of the (winter) sun

For decades, Vorarlberg's roofs have been adorned with modest-sized solar thermal systems, just a few square meters to heat water. This has changed - the photovoltaic system model could now actually pay off, explains author and natural scientist Christian Mähr. 

We are seeing more and more photovoltaic systems for generating solar power, most of them much larger than the familiar collectors. As we know from the past, their efficiency is several times lower than the thermal collector efficiency, which is why larger surfaces are needed. But wait a minute! Isn't this photovoltaic stuff a niche product for rich eco-freaks, i.e. really expensive?