October 21, 2024|General

Heating with photovoltaics – sustainable, efficient and cost-saving

As the heating season approaches, many households are searching for cost-efficient and sustainable solutions for heat supply. One option is the use of photovoltaic (PV) systems for heat generation. With rising electricity prices and decreasing feed-in tariffs, self-produced PV energy is a valuable resource that should be optimally utilized – especially for heating your home.

For homeowners with PV systems regularly generating surplus electricity, an important decision arises: Should the surplus electricity be fed into the grid for just a few cents per kilowatt-hour, or used for self-consumption? The answer is clear: it is both economically and ecologically smarter to use the surplus PV electricity within your household – for example, for heating water or supporting the heating system.

With my-PV solutions, your photovoltaic system can be used efficiently year-round. Our devices enable you to optimize the use of self-generated PV energy to operate your hot water and heating systems in an environmentally friendly and cost-effective way.

How electric heating with photovoltaics works

To successfully implement electric heating with photovoltaics, you need a well-insulated building and a powerful PV system that ideally covers the entire roof and, in some cases, even integrates vertically into the façade. If the heating energy demand is less than 50 kWh per square meter annually, electric space heating can be efficiently powered by PV electricity.

Photovoltaic energy is particularly effective for use in surface heating systems such as underfloor or wall heating. Devices like the AC•THOR or AC•THOR 9s also provide a thermal storage function, where building materials like screed absorb heat and release it during the night.

Linear control

A key factor for efficiency in PV heating is the intelligent control of PV electricity. With my-PV solutions, the generated surplus electricity can be regulated linearly and precisely.

Even in winter, when the days are shorter and sunlight is less intense, a well-dimensioned PV system still produces significant energy. Thanks to the linear control of my-PV devices, the entire yield can be used precisely and without loss for space heating.

Good to know

Our devices can be seamlessly integrated into existing hydronic heating systems. Heating elements can either be installed in combination or buffer tanks or be connected as two separate units for the hot water tank and heating buffer. This makes it possible to utilize surplus PV electricity even in older or existing heating systems.

The photovoltaic power managers AC•THOR and AC•THOR 9s ensure that the available energy is optimally used and distributed across the household. They allocate PV electricity among various consumers, ensuring an even heat distribution, especially on days with variable sunlight, such as during cloudy weather.

Cost savings and environmental impact

By coupling the PV system with the heating system, the heating load in winter is significantly reduced, leading to substantial savings in energy costs. Compared to conventional heating systems, such as air source heat pumps, up to 30% of the investment costs can be saved. Operating costs are also reduced by about 30%, as the need for grid electricity decreases. Moreover, maintenance costs are almost non-existent since there are no complex mechanical components. Energy is produced and consumed on-site, reducing reliance on grid power and keeping operating costs consistently low.

Two examples of electric heating

A practical example illustrates the use of heating with photovoltaics: In a single-family house in Upper Austria, the entire heating system was powered solely by PV electricity until mid-November, without the support of a conventional heating system. The AC•THOR 9s optimizes the self-consumption of PV electricity, shortening the heating period – the homeowner only needs an additional heat source during December and January. This reduces energy consumption and heating costs while saving large amounts of wood.

To the project description

Another example is a fully solar-electric reference project in Upper Austria. With only €750 in annual operating costs for electricity, hot water, and heating, the single-family house is highly than cost-effective.

AC•THOR 9s replaces the conventional home technology and enables both water heating and building heating with solar power.