Good Day, Sunshine!
Solar energy explained in a nutshell
There’s an eight minute journey for light to get to from it to the earth. In three hours, it produces as much energy as we consume on earth in one year. And if you get too close to it (say, on the planet Mercury), you need a 10,000x light protection factor.
Of course, we're talking about the sun. The source of all life & galactic power, which is almost unlimited. So what do we do with it? How far can we power ourselves with solar energy & how exactly can we use it? These questions & others that we frequently receive on our social media challenged will be answered here.
Solar thermal energy or photovoltaic - which is better?
Neither. They are two techniques that use the power of the sun in different ways. In the case of solar thermal energy, heat or hot water is generated and photovoltaic electricity is generated.
The use of solar thermal energy goes back to ancient times, as, for example, hollow mirrors were aligned with the sun in order to heat the houses in the cool season. For more than a hundred years, solar thermal energy has been used around the Mediterranean to produce warm water using solar collectors. This technology is considered to be robust and inexpensive and has been used for a long time throughout the world.
Photovoltaic (PV) is a much more sophisticated technology, in which the sun's radiation is converted into electricity. As inconspicuous as a solar cell look, there is a lot of modern technology inside of them. Numerous thin layers of different materials interact with each other to generate electricity. Their highest yield is achieved by PV systems not in the summer, but in the spring, since the greatest efficiency occurs with milder temperatures.
And when the sun doesn’t shine, do we then need candles?
If you have a date: absolutely! Apart from that, there are now efficient solutions when the sun doesn’t shine.
PV systems operate with light and do not necessarily require undisturbed contact with the sun. Of course, the yield is higher when the panels are directly exposed to the sun.
At night, there is so little light that the system no longer produces electricity. This creates a bottleneck that cannot be disregarded when compared to other forms of energy generation. But there is a remedy: storage solutions especially for private use, such as the AURA system. This is ultimately a large, powerful battery, which stores the generated electricity during the day, so that it can be used at night. This means that the share of the solar power consumption can be increased from 30 percent to 70 percent.
I am not a handyman - can I do the maintenance?
Solar energy systems are designed and installed in such a way that they generate energy for a long period without maintenance. There are no moving parts and the materials are weather resistant.
The performance of a system is permanently monitored and problems can be detected at an early stage. Typically, the systems are free from major problems, but they should be cleaned regularly to ensure maximum energy yields.
Do I need permission to install a solar panel?
Most likely not - but there are exceptions. The construction of a conventional solar energy system on a roof is basically fine to do without permissions. But if the system is structurally different from the usual standards, approvals may be required.
- Facades that protrude from the building
- Particularly large or high systems or houses
- Public or historical buildings
- Equipment that is installed over people’s heads
Can I even afford to put PV panels on my roof?
The price of panels depends on many factors, such as size, consumption rate, current electricity price or location. There’s a simple rule of thumb: At present, private customers pay about 1,400 Euros per kilowatt peak power (kWp), according to the German Federation of Solar Energy.
A PV system for a single-family house therefore costs between 4,500 and 14,000 Euro, depending on power (3-10 kWp), size and supplier. For insurance, maintenance, etc., makes up about one to two percent of the investment costs which are accrued annually. In the case of private consumption systems, the costs for the storage are added. Depending on the capacity, the prices are starting at 4,500 euros. The AURA battery system including a photovoltaic system from E.ON is available from 9,799 euros. After approximately twelve years, the plant is normally amortized. By the way, you can calculate the prospective annual income of your investment directly with us - thanks to our cooperation with Google's Sunroof.
“Can I use solar energy even if I rent?”
It used to really be that way. Solar energy predominantly was found as photovoltaic (PV) systems on the roofs of small and medium-sized houses and was just used by the owners. Tenants in apartment complexes didn’t have the possibility to buy solar power.
But intelligent networks, decentralized energy generation and modern storage solutions have led to a much more flexible use of solar energy - even at night. E.ON can guarantee that our solar tariff comes 100% from the sun. Even if, for example, you live in a large apartment complex that does not have a PV system.
In addition, the producers of solar power, such as the homeowners mentioned at the beginning, have the possibility to take the solar power with them everywhere. This concept works similar to the way that large amounts of data on the Internet are stored through the "cloud". Cloud solutions, which work according to the same principle as data clusters, enable the solar power producer to use the environmentally friendly energy anywhere, regardless of location and time.