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For a long time, private homeowners could only sell their surplus solar power to their local or regional energy supplier. In return, they received a feed-in or feed-back remuneration, which is determined by the supplier once a year and varies greatly from region to region. For example, someone feeding solar power into the grid in Hasliberg received 40.258 centimes per kilowatt hour in the 3rd quarter of 2022, but only 5.4 centimes in Meiringen, because two different energy suppliers supply the two neighboring communities in the Bernese Oberland. Because of rising energy prices, the private solar power market in Switzerland is slowly but surely starting to move: the Centralschweizerischen Kraftwerke has been paying prices in line with the market since the fall of 2022 and buying solar power from private customers in other areas. Other energy suppliers are following this example.
The feed-in or feed-back remuneration was previously not linked to any market price and was usually significantly lower than the price you paid for electricity from the grid. Now, more and more suppliers are paying a market-based compensation that is based on the reference market price for photovoltaics set by the Swiss Federal Office of Energy. This reference market price is the average of the prices set on the Swissix power exchange in any given quarter for the following day. The reference market prices in 2022 (average 26.970 centimes per kilowatt hour):
The energy suppliers deduct a so-called service charge from the reference market price. CKW, for example, charges 8 centimes per kilowatt hour, whereas others charge 4 centimes.
In principle, you could sell all the solar power you produce with your photovoltaic system. However, this does not make sense, because you need electricity for your house, your household and your electric car, which otherwise you would have to buy more expensively. Therefore, you only sell surplus power that you do not need. How much depends on your electricity consumption and production.
If you want to sell your solar power to a supplier other than your local or regional one, your photovoltaic system needs a load-capable meter.
If you can't remember how much electricity you use, you should be able to find the consumption information on your last 12 months' bills or online on your energy supplier's customer portal. The average household in the average single-family home uses about 4,500 kilowatt hours of energy per year. If you own an electric car that uses 15 kilowatt hours per 100 kilometers and you drive it 10,000 kilometers a year, that adds about 1,500 kilowatt hours of energy a year. That makes 6,000 kilowatt hours for the house and car.
If you don't know how much solar power your photovoltaic system produces, you can estimate its output with our solar calculator. A 50 to 60 square meter photovoltaic system produces about 10 kilowatt peak, which should be enough for 10'000 kilowatt hours of solar power per year. Theoretically more than enough to cover the energy consumption of 6,000 kilowatt hours in our example, if the photovoltaic system achieves a self-consumption share of at least 60 percent.
Photovoltaic systems without storage achieve a self-consumption share of 30 to 35 percent. Why? Households consume the most energy in the morning and evening, photovoltaic systems produce the most electricity over midday. Without storage, you would have to draw 65 to 70 percent of your electricity from the grid, even though your photovoltaic system produces more than enough solar power. With a smart storage solution, you double your self-consumption percentage, use more cheap solar power, don't have to buy expensive power from the grid, and sell your excess solar power.
How solar power storage works and what speaks for or against it you can read in our article «Electricity Storage: Is a Storage Device for the Solar Power System Worthwhile?».
You sell your surplus solar power either way. Either to your local or regional energy supplier or to another one. The only question is how much you get for your electricity. In this simple example, we calculate income and expenses for an average single family home in the city of Winterthur. The key points:
In this example calculation, the owner of a single-family home earns 551 Swiss francs when he sells his solar power to the Winterthur municipal utility and saves 1,696 Swiss francs a year thanks to his photovoltaic system. If he sells his solar power to a supplier who pays him the reference market price, he earns 2,177 Swiss francs and saves 3,201 Swiss francs a year. The reference market price depends on the prices on the electricity exchange. And like on any stock exchange, prices can rise or fall. There is no guarantee or certainty that the reference market price will not fall below the feed-in remuneration. In the example, the calculation works out as long as the single-family homeowner receives more than 22 centimes per kilowatt hour (14 centimes feed-in remuneration plus 8 centimes service fee). As soon as the reference market price in this example falls below 22 centimes per kilowatt hour, the single-family home owner would have been better off with the feed-in remuneration from his energy supplier.
The Association of Swiss Electricity Companies is calling for a central body that buys solar power from all over Switzerland and remunerates it at a uniform market price.
Most local or regional suppliers pay something for the certificate of origin with the feed-in remuneration. If you sell your solar power at the reference market price, you must market the certificate of origin yourself, for example on the green power exchange.