As described in Chapter 2, solar thermal energy converts solar rays into heat. Photovoltaics is another way of using solar energy. This technology is based on a well known effect in physics: some semiconduc­tors convert light directly into electrical current. This chapter focuses on the main applications and the future of photovoltaics as seen from […]

Hydropower has been used for centuries in Germany. Often, hydropower was the start­ing point for merchants and cottage industries (mills, pumps, etc.). Starting in the mid-19th century, hydropower was used to generate electricity, and up to 2003 it was the largest source of renewable electricity in Germany. Today, hydropower provides some 20 billion kilowatt-hours of […]

Before feed-in rates were offered for solar power starting on 1 April 2000, there was a tremendous difference between the cost of such systems and the amount paid for solar power. In 1999, around 8 eurocents per kilowatt-hour was paid for one kilowatt – hour. If array owners sold all of their power to the […]

There are dark clouds on the horizon. Climate change – long researched, discussed and denied – is increasingly making its pres­ence felt. Drawn up by more than 2000 climate researchers from around the globe, the International Panel on Climate Change’s (IPCC) 2007 report has a clear message: the Earth will inevitably heat up by more […]

In 1992, the Fraunhofer Institute for Solar Energy Systems opened its Energy- Autonomous Solar House in Freiburg, Germany, as a research and demonstration project.21 With 145m2 of floor space on two stories, it has five rooms, a kitchen and ancil­lary rooms. This house proved that a single-family home could make do with the solar energy […]

‘The only thing that comes out of the exhaust is water vapour!’ In light of climate change and smog, such statements seem attractive at first. No wonder most major car manufacturers have been working on fuel cell cars at some point or another;16 these cars would have electric drive trains powered by electricity from fuel […]

The 1986 reactor catastrophe in Chernobyl finally made everyone realize what the risks of nuclear power are. But climate change has since made it clear that our current energy supply system also poses tremendous risks. The energy sector is taking advantage of this new situation to play one risk off against the other; in the […]

More efficient pumps and pump controls would save many billions of kilowatt-hours of electricity and heat in homes, businesses and industrial plants. But this change would require decision-makers to be better informed and tradespeople better trained; in addition, we would need an investment philosophy that accepts higher investment costs in return for lower operating costs.27 […]