The new solar-electric heating element in use

AC ELWA 2 in an architect's house

The new solar-electric heating element in a renovated single-family home in Upper Austria.

Facts about the project

PV power and orientation
Type of building
Year of construction and construction size
Heat storage size
my-PV product in use:
System control by:
230906_Referenz AC ELWA 2_Gasselik_Drohnenbilder (1) my-PV

Short explanation of the system and the way to my-PV

The graduate in architecture and holder of the certificate of qualification for building trade, Dipl.-Ing. Markus Gasselik from the district Vöcklabruck in Upper Austria, is highly aware of the value of modern, contemporary building technology. He was one of the first customers who were able to enjoy the latest solution from my-PV in the summer of 2023. His old single-family home (built in 1950) was extensively renovated and expanded in 2012 and now offers more than 200 square meters of living space for his family of four. All planning and construction work was carried out by the owner himself.

Back in 2005, the aim was to switch the heating system from oil to pellets. A conventional solar thermal system with a corresponding combination storage tank was originally planned for hot water preparation. However, the outdoor units were never carried out.

The project manager of building construction projects and owner of the renovated single-family home came across my-PV through an interaction in person. In spring 2020, a photovoltaic system was installed instead of a solar thermal one – a total of 5.2 kWp (facing southeast with two different inclinations). This means that excess PV yields are already generated in the morning hours, which were unprofitably fed into the grid until the AC ELWA 2 was installed. It was therefore obvious to the family not only to support electricity consumers with the solar power they produced themselves, but also to use the surplus to generate heat across sectors. The existing combination storage tank with a volume of 800 liters offered a suitable screw-in point in the middle with a 1.5 inch connection, perfect for installing the AC ELWA 2. Since this is a standard size, it is possible to subsequently install the device in many other hot water or buffer tanks. The photovoltaic system was intended not only to partially cover household electricity, but moreover – instead of the usual feed-in – to achieve the maximum in terms of self-consumption: this paved the way for photovoltaic heat. The hot water is now prepared with the photovoltaic electricity produced.

How was the installation of AC ELWA 2?

“The installation of the AC ELWA 2 was uncomplicated, and the hot water preparation works perfectly. “One day there was no data to be seen in the new my-PV Cloud, but the problem was my router (which I was able to fix with a restart),” says Markus Gasselik, summing up his previous experiences with the solar electric heating element.

How many people live in the single-family home?

Two adults and two children (10 and 13) live in the single-family house, which was renovated in 2012. The hot water requirement is approx. 48 m³/year, with the hot water being prepared using pellet heating during the heating period. This means that the pellet heating system can remain switched off during the high-yield photovoltaic months from spring to autumn and is thus protected.

Is the hot water supply used with mains electricity?

The hot water backup is only used during the summer months. This means that the biomass boiler can be switched off completely during the warm months of the year. The boiler output is already dimensioned for space heating, so the owner avoids short operating times or partial load operation of the pellet system, which should benefit the service life.

Personal customer opinion and resumee

After a few weeks of operation with the AC ELWA 2, the innovative customer is very satisfied. Operation in winter is still pending, but the data for this will of course only be collected in the near future. “The AC ELWA 2 keeps its promises. The installation was uncomplicated, as was the commissioning – I would absolutely recommend it!” says Markus Gasselik, summing up his impression of the solar-electric heating element.

230906_Referenz AC ELWA 2_Gasselik_Drohnenbilder (1) my-PV
230906_Referenz AC ELWA 2_Gasselik_Drohnenbilder (1) my-PV
230906_Referenz AC ELWA 2_Gasselik_Drohnenbilder (1) my-PV
230906_Referenz AC ELWA 2_Gasselik_Heizraum (7) my-PV

AC ELWA 2 in use

Make the most of solar energy and increased self-consumption

To maximize the self-consumption of your current PV system, AC ELWA 2 harnesses the system's surplus photovoltaic energy to heat your water. Increasing self-sufficiency simultaneously safeguards against unpredictable or rising operating costs.

More infos about AC ELWA 2

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