Solar Power System Case Study


When renovating their house, Kai and Jana stuck to their motto of “All or nothing.” Almost all areas of their home were optimized or remodeled to be more energy-efficient, including the installation of a PV system. Their main goal was to reduce energy costs and do something positive for the environment.

“When looked at objectively, there is no good reason not to install a PV system,” says Kai. Because producing solar energy is always a good idea. Just the feeling of no longer having to purchase electricity from the utility grid for the majority of their needs is very important for Jana and Kai. “We are part of the energy transition,” they both claim with an obvious feeling of pride.

By installing a PV system Kai and Jana wanted to achieve the following:

  • Reduce energy costs, especially for electricity
  • Gain more independence from energy suppliers
  • Invest in the future
  • Produce a sustainable and uninterruptible power supply
  • Take part in the energy transition


After replacing all their windows, doors and the roof, as well as insulating the walls of their home, 40 PV modules were installed on the west-facing part of their roof. A solar inverter, which is the true heart of a PV system, was also installed in no time.

“We decided to use the entire area of the roof—despite the trend toward smaller systems. Basically, the system’s output—and therefore production—will be adapted to the home’s consumption needs. The price of PV systems has been falling for several years and is reflected in the affordable deals being offered by installers,” explains Kai. The slightly excessive size of the PV system does not bother either of them. Ultimately, you never know what the future will bring: “There may be children at some point, which could mean higher power consumption,” says Jana. But there may also be a system upgrade to include a storage solution. “Having a smart home is awesome,” adds Kai.

The following components were installed on and in Kai’s house:

  • 40 x Yingli Panda 265 W monocrystalline modules with a total output of 10.6 kWp
  • Sunny Tripower 9000TL
  • Sunny Places/Sunny Portal


Jana and Kai are trying to consume as much power produced from their roof in their home as reasonably possible through so-called “natural” self-consumption (which is estimated at about 30 percent).

“Of course, I pay attention to when I turn on the washing machine and dishwasher. However, I don’t need to make any extra effort, because you can preset most modern household appliances to run in the mornings and be finished at night,” says Kai. “It’s a good feeling to know that every day the sun shining on the roof is directly powering all of our electrical appliances. Regardless of whether you are vacuuming or cooking,” adds Kai.

Additional bonus points for both include:

  • Detailed and transparent display of the PV output via Sunny Places/Sunny Portal
  • Conscientiously managing energy
  • Very fast amortization of the system expenses, which are constantly falling anyway


The PV system installed on Jana and Kai’s house consists of modules on the roof and the SMA inverter in the basement. The system’s monitoring and display are handled by Sunny Places or Sunny Portal, the world’s largest online portal for PV systems.

An overview of the SMA components in the PV system:

Sunny Tripower 9000TL

Sunny Tripower 9000TL

The Sunny Tripower PV system with 5 to 9 kW of power is setting new standards for home systems, making it a leading-edge technology for top yields and complex requirements.

More about the Sunny Tripower 9000TL

Sunny Places

Sunny Places

Integrated access to Sunny Places not only gives you an overview of your PV system’s energy data, it also lets you compare your system’s performance with that of other systems.

More about the Sunny Places