Germany goes for solar

Albert Einstein discovered the theoretical foundations on which photovoltaic cells are based a hundred years ago — it was a spin-off from his annus mirabilis. Half a century ago, Bell labs built solar cells out of silicon, which soon came to be used in space flight. But the real breakthrough in solar cells was neither theoretical, nor experimental. It was a simple pecuniary reward. Since the 1980s it had been a pet policy of Germany's Green Party that people who put solar cells on their roofs should have the right to sell back any excess electricity to the providers at a rate exceeding the one they pay for the power received. Soon after the party came to power in Schröder's Red-Green coalition in 1998, this simple idea known as a feed-in tariff (FIT) became law without much ado. The Erneuerbare-Energien-Gesetz (EEG; renewable energies law) came into force in April 2000, and it changed the economics of solar cells fundamentally. Before the FITs, installation of solar cells had been a costly sacrifice only embraced by a small minority of affluent planet-savers. In 1996, for example, the weekly Die Zeit reported that the solar cell surface amounted only to the size of two postage stamps per head. The high cost of producing small numbers of photovoltaic cells conspired with the relatively poor efficiency of cells to make investment in photovoltaic power less than attractive, even though there was a widespread awareness of environmental problems and climate change already. Alternatives, such as the direct collection of heat rather than electricity, saw some success in the 1980s and 1990s (thermal cells produced by companies such as Thermosolar), but photovoltaics stagnated and some companies folded or left the country. The outlook for green electricity became a lot sunnier when FITs were introduced. Since then, everybody who sets up a renewable energy facility — be it solar, wind, or hydroelectric — can sell back excess electricity to the energy providers. After another modification to the law, grassroots energy producers are now paid at four times the market rate for at least 20 years. Typically, people earn back their investment within 10 years and then start to make actual profits from their green actions. Accordingly, the number of photovoltaic devices in Germany has grown more than 11-fold since 2000, from 29,000 to 330,000. Thermal cells, which don't generate electricity but which are more affordable to install in …