my-PV Referenzprojekt ELWA Harz PV-Module

Hot water with the sun in Germany

The sun sends no bill: Thanks to ELWA, the sun provides hot water at no cost, even in the German Harz region.

In the rainy Harz region in central Germany, in a brick-clad old building in the Lower Saxon city of Goslar, hot water is prepared sustainably and environmentally consciously. The setup includes a 200-liter hot water tank, a house from the late 70s, as well as a 105 m² living space in a 2-person household – great conditions to use solar energy, namely with the ELWA from my-PV. Within the off-grid system, electricity from some PV modules is directly passed on to the ELWA, eliminating the need for inverters, grid registrations, and bureaucratic paths.

An escape from rising gas prices

Faced with the surge in gas prices in 2022, Mr. Zogbaum, like many of our customers, sought an alternative for his gas condensing boiler. The lack of supply security coupled with unpredictable political decisions, impeded the continuation of the existing technology.

For over a decade, Mr. Zogbaum had relied on a gas condensing boiler with the belief that it was the optimal heating system. “What has always bothered me was the fact that in summer, I had to leave the heating switched on solely for hot water. My gas consumption in the summer was about 150 kWh per month, purely for hot water,” calculates Mr. Zogbaum, highlighting the use of gas in the summer for hot water preparation, which is economically not meaningful.

With the new solution, the ELWA from my-PV, the gas heating remains turned off until October, so the hot water is supplied free of charge by the sun.

How the path to my-PV unfolded in detail and why the customer did not install a heat pump? You can read about it in the comprehensive reference description of this project.

my-PV Referenzprojekt ELWA

Click here for the reference description

How exactly was the project implemented? Read the detailed project description for more information.

More information about the project

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