Electric radiant and large-area heating – comparison of heating costs

What is the most suitable heating system to choose? There are plenty of solutions, and suppliers of each type always highlight the strengths of their heating system. A practical tool that compares annual costs not only for heating but also for the preparation of hot (domestic) water, other electricity consumption, and the annual share of costs for the acquisition of the heat source and heating system is the calculation tool of the portal tzb-info.cz "Comparing Heating Costs TZB-info".

This calculation tool has been available here for many years; however, at the turn of 2012 and 2013, a new modified version was launched. Unlike the original version, it now includes not just annual heating costs but also those for hot (domestic) water preparation, other electricity consumption, and the annual share of costs for acquiring the heat source and heating system. The results from this comparison thus provide a much more objective basis for decision-making regarding fuel choice and type of heating when building a new home or renovating a heating system.

The graph indicates that electric direct heating (preset to electric floor heating) is the second most cost-effective system. However, it is also important to emphasize that a ground/water heat pump with a high coefficient of performance (COP) of 4.3 and a lifespan of 30 years is taken into account. If a more commonly used air/water heat pump is compared, the graph of the advantages of the individual systems will change as follows:



EXAMPLE 2:
As heat losses in new buildings continue to decrease, and today a heat loss value of around 3-4 kW is standard, the heat loss of the building in the calculation tool has been decreased to 4 kW. Other values remained at their default settings:
•    Calculated outdoor temperature: -15°C
•    Floor area: 150 m2
•    Calculated heat loss: 4 kW
•    Hot water: 55°C for 4 people at 50 l/person 365 days/year
•    Electricity consumption for other appliances: 3,229 kWh/year



With heat losses of 4 kW, electric direct heating is the most advantageous, even compared to a ground/water heat pump with a COP of 4.3.

EXAMPLE 3:
An interesting result is also observed when the heat loss of the house is set to 3 kW, and forced ventilation with heat recovery is considered (standard for low heat loss houses):
•    Calculated outdoor temperature: -15°C
•    Floor area: 150 m2
•    Calculated heat loss: 3 kW
•    Controlled ventilation with heat recovery (efficiency 75%)
•    Hot water: 55°C for 4 people at 50 l/person 365 days/year
•    Electricity consumption for other appliances: 3,229 kWh/year



The graph clearly shows that for buildings with low heat losses and controlled ventilation, electric direct heating is the most optimal choice.

What do the examples suggest? That the new calculation tool aligns with real-world experiences. FENIX Jeseník, our largest manufacturer of electric heating systems, supports several projects for the construction of low-energy houses, both brick and based on light prefabricated wood, where they monitor and evaluate the operation and energy consumption. The experiences of contractors, manufacturers, and investors confirm that if a building has good thermal-technical properties, correctly implemented electric floor or ceiling heating is economically very advantageous. Low acquisition costs, practically zero maintenance costs, unattended operation, and above all, precise regulation clearly speak in favor of electric heating in this case.