Single-family home – Scholz

Kundenerklärung

"The EEG remuneration for our PV system expires in October 2022, so the transition to self-consumption should take place gradually. In October 2019, we decided to aim for this goal starting in 2020, as our old thermal solar system could only cover the hot water demand in the summer. Our solar system installer then made us aware of my-PV. Converting surplus electricity into heat was a way to become more independent in heat generation as well. Purchasing a conventional solar system was no longer an option due to the changed yield and cost situation."

Since we were unable to retrofit our 1,000-liter buffer tank with heating rods, the connections of the dismantled solar thermal system were simply used for heat delivery. An external heat exchanger was custom-built, and the 9 kW screw-in heating element from my-PV was installed in it. The AC•THOR 9s controls the stepless power regulation of the heating element. In M7 operating mode, it is also capable of precisely controlling the speed of a Wilo heating pump. This ensures that the amount of hot water pumped from the heat exchanger into the buffer is always accurately dosed, guaranteeing thermally ideal charging of the storage tank.

Right after the implementation of the measure in spring 2020, significant PV heat yields were already achieved. In March alone, 799 kWh of energy for hot water and space heating were made available – clean and renewable energy from our own roof. Just one month later, in April, the first milestone of the year was reached with 1,036 kWh of heat yield.

By converting the PV surplus electricity into heat, the operating time of our combined heat and power unit (CHP) has significantly reduced. Starting in 2022, when the old PV system expires from the EEG, the full 19.5 kWp will be available for self-consumption. The CHP will only be needed at most in December and January, and for the rest of the year, sufficient heat will come from our photovoltaic system via the AC•THOR 9s to supply the entire house*, calculates the builder Gerhard Scholz.

* renovated old building, 16,000 - 17,000 kWh/year for hot water and heating, 2,500 - 3,000 kWh/year for household electricity

Product details AC•THOR 9s:

• 0 – 9,000 W stepless regulation

• Maintenance-free through "cables instead of pipes"

• Reduction of the technical room size

• Open system for various inverters, battery systems, and smart homes

• Easy installation, user-friendly

• Enables affordable housing even in residential construction