Solar energy
Solar energy can be harnessed in two ways: via heat and via light. Water, for instance, can be heated for household use with the aid of a solar collector. And solar panels can be employed to convert sunlight into energy.
Solar collectors
Water in a solar collector basically heats up according to the same principle as water in a garden hose that has been lying in the sun all day. Even in the winter, when the sun only shines for a few hours, a solar collector can produce sufficient hot water to shower, wash or clean. Some systems also help to heat the house.
Solar panels
Solar panels consist of solar cells that are usually made of silicon. The silicon consists of two layers. The trapped light causes an electrical current between these two layers. The professional term for solar panels is 'photovoltaic cells' (from phos = Greek for light, and Volta, after the unit of electric current). These are also called PV systems, for short.
Solar cells even work when the skies are overcast. Clouds only stop part of the sunlight, whilst diffusing the rest of the rays. In the Netherlands the sun actually yields 2/3rds of the energy produced on the French Riviera where there is much less cloud. Solar panels are usually mounted on rooftops. Their useful life is about 25 years.
Solar energy projects of Nuon
Nuon operates several solar energy projects in the Netherlands, ranging from rooftop solar arrays on the Dutch Central Bank in Amsterdam and a large overarching roof over the former Floriade Festival site (Haarlemmermeer Polder) to solar panels on a sound barrier along the A9 motorway. All projects jointly have a capacity of some 7,500 kWp. Nuon thus produces 4,800,000 KWh, which is equal to the annual electricity demand of 1,400 households.