ELECTRIC DIRECT HEATING IN COMPARISON

ELECTRIC DIRECT HEATING IN COMPARISON

RECOMMENDATION FOR ELECTRIC DIRECT HEATING IN COMBINATION WITH PHOTOVOLTAICS New study for Austria

Modern electrical panel heating in connection with photovoltaics is worthwhile from both an ecological and economic point of view. This is the result of a new study for Austria based on the European EUHA study Energy Efficiency and Cost Effectiveness of Electrical Heating in Combination with Photovoltaic Systems, in which gas condensing boilers, electric air-water heat pumps and direct electric heating are each combined with photovoltaics system were compared.

In well-insulated buildings in particular, modern electric heaters in combination with photovoltaics perform significantly better than conventional gas heaters in combination with photovoltaics. Thomas Reiter, Managing Director of ETHERMA - one of the leading providers of innovative electric heating: "We are very pleased that the independent study confirms our own investigations. In modern, thermally insulated buildings, electric surface heating is more than an alternative to other heating systems. They are clean , intelligent, scalable and forward-looking."

Time for a re-evaluation of the heating systems

According to calculations by the Federal Ministry for Climate Protection, Environment, Energy, Mobility, Innovation and Technology, around 10 percent of harmful greenhouse gas emissions in Austria are caused by heating and hot water systems in buildings. A new European EUHA study (Energy Efficiency and Cost Effectiveness of Electrical Heating in Combination with Photovoltaic Systems) for Austria, commissioned by the Association of Electric Heating Austria and IG Infrared, shows the savings potential for the building sector.

The result: With the combination of solar power generated close to the building and electric surface heating, environmentally friendly and economically attractive solutions can be implemented. In well-insulated buildings in particular, modern electric heaters in combination with photovoltaics perform significantly better than conventional gas heaters in combination with photovoltaics.

Thomas Reiter, CEO of ETHERMA - one of the leading providers of innovative electric heating: "We are very pleased that the independent study confirms our own investigations. In modern, thermally insulated buildings, electric surface heating is more than an alternative to other heating systems. They are clean , intelligent, scalable and forward-looking."

The requirements of the study

The EUHA study was carried out by the independent Institute for Technical Building Equipment Dresden Research and Application GmbH and compares different system technology variants for a single-family house in terms of energy efficiency and cost-effectiveness. The basis of the calculation process was the European standard EN 15316, with which a neutral calculation of the annual energy requirement of a building was carried out. In terms of space heating, a comparison was made between gas condensing boilers, electric air-to-water heat pumps and direct electric heating - each in conjunction with a photovoltaic system. In addition, systems for heating drinking water and the use of power storage batteries were also taken into account in the overall considerations of the study. In a subsequent study based on this, the above procedures were applied to Austria.

Leader in cost savings and longevity

According to the study, electric underfloor heating, with an average one-off investment cost of EUR 9,000, is significantly cheaper than gas condensing boilers (EUR 3,600 plus EUR 11,300 for hydraulic underfloor heating) and electric air-water heat pumps (EUR 9,500 plus EUR 11,300 -- for hydraulic underfloor heating). In addition, both gas heating and the heat pump incur annual costs for maintenance and servicing, while the electric heating is operated maintenance-free over its entire life cycle (see Fig. 1). 

The average service life of the systems must also be included in the profitability analysis. The electric underfloor heating with a service life of 50 years is also convincing here. Hydraulic underfloor heating achieves the same value, but the gas condensing boiler and heat pump have to be replaced after an average of 18 years.

Very good results in sustainability

The calculations of the study on the primary energy requirement and greenhouse gas emissions are complex and take into account numerous factors, including hot water generation, battery use and different statistical sources. In general, it can be stated that in combination with a photovoltaic system, electric air-to-water heat pumps have the lowest emissions, closely followed by direct electric heating. If you also take the feed-in bonus into account, both heating systems lead to savings in greenhouse gases in houses with a high level of thermal insulation. However, the solutions with an electric air-water heat pump require significantly higher financial expenditure.

As a result, the following is recorded for electric heating in connection with a photovoltaic system:

On the basis of current energy prices - electrical energy is more than three times as expensive as gas in Austria - direct electric heating scales better with the energy requirements of the building; i.e. H. you benefit e.g. stronger of better structural heat protection.

With the low Austrian primary energy factor for electrical energy, direct electrical heating in comparable cases (identical buildings with photovoltaics) should always perform better or significantly better than gas heating in terms of primary energy. Due to the significantly higher electricity price, directly electrically heated variants scale slightly better with the energy requirements of the building than gas-heated ones - i.e. by reducing the building's energy requirements (e.g. better structural thermal insulation), more energy costs can be saved with direct electrical heating than with gas heating.

Outlook on profitability and future security

The study also looks to the future. It is expected that the current economic and energetic advantage of direct electric heating in combination with photovoltaic systems and battery storage compared to gas heating will increase significantly. This is mainly due to the fact that significant innovations in terms of efficiency and cost advantages compared to fossil fuels can still be expected both in storage media and in the generation of regenerative energy.

The study on this:

While gas condensing boilers are an established, proven and mature technology, they no longer offer any significant potential for increasing efficiency and/or reducing prices. In contrast, photovoltaic systems and electrochemical batteries are still relatively young in this context and on this scale.

In comparison, electrochemical batteries for the purpose of short-term storage of photovoltaic yields have only just begun to establish themselves on the market. In its early days, this still young market was split between lead- and lithium-ion based battery technologies; today it is practically dominated by lithium-ion-based technologies. This rapid and still ongoing development is essentially driven by electromobility and its enormous need for high-performance/capacity cells and the associated technical developments and economies of scale.

It is also to be expected that energy from renewable sources will become cheaper than today in relation to conventional energy sources (e.g. through the introduction/increase of emission taxes on fossil fuels). This does not mean that energy will become cheaper than it is today; however, in the medium term, the prices of fossil fuels are likely to rise more sharply than the prices of energy from renewable sources.

Source of Figures 1 & 2: Study of energy efficiency and profitability of direct electric heating in combination with photovoltaics in Austria based on the European EUHA study; FEEI Management Services GmbH; Dresden; 07/28/2021