Inhalt:
Frequently asked questions
- What is “photovoltaics”?
- How does a solar cell work?
- What is the difference between a solar cell and a solar thermal collector?
- Where does the solar electricity go if I don’t need it but the sun is shining?
- How can I take advantage of my solar energy at night?
- How much solar energy does a 4/5 person household in Switzerland need?
- How long does it take for the solar cell to produce as much electricity as was needed for its manufacture?
- Isn’t the efficiency of solar cells far too low to justify their use?
- How long do solar cells last?
What is “photovoltaics”?
The transformation of light energy (photo) into electrical energy (voltaics).
How does a solar cell work?
It consists of a thin semiconductor layer with a positive and negative pole: when light falls on the cell an electrical voltage between the two poles is generated.
What is the difference between a solar cell and a solar thermal collector?
Solar cells convert light to electricity, solar thermal collectors produce heat (hot water).
Where does the solar electricity go if I don’t need it but the sun is shining?
Either it is fed into the public grid or (in areas with no main electricity connection) it can be stored in an accumulator and used later.
How can I take advantage of my solar energy at night?
The electricity can be fed into a grid during the day, and drawn out at night, or it can be stored in an accumulator for later use.
How much solar energy does a 4/5 person household in Switzerland need?
5-6 kW for a total of about 4850 kWh annually.
How long does it take for the solar cell to produce as much electricity as was needed for its manufacture?
From 4 to 18 months depending on the cell type. Every half hour, the earth receives enough sunlight to provide for mankind’s annual energy requirements. The energy is there, we just need to make use of it!
Isn’t the efficiency of solar cells far too low to justify their use?
As solar panels are used for building cladding, the surface area used and the efficiency are immaterial – what is relevant is the price compared to electricity production or yield. 10% of all Swiss roof and façade surfaces would cover 20% of our electricity requirements.
How long do solar cells last?
They are expected to last at least 30 to 40 years.
