Over the years, while working at KOSPEL SA, you have witnessed changes in the energy market. Where are we now?
In recent years, we have seen a strong drive towards low emissions and improved air quality. Many energy-saving facilities are being built and we are increasingly choosing renewable energy sources for the needs of individual households - this is a huge change. Unfortunately, in Poland this process is progressing quite slowly. We still lead in pollution caused by the use of fossil fuels. It is very important to build ecological awareness, but also to meet the needs of owners of old solutions who plan to change their current heat source. Therefore, in Kospel educational materials, we pay attention to good practices, as well as subsidies for such activities. If we can afford to replace the old type boiler with a new generation boiler, even if it is still powered by solid fuel, we are already contributing to improving the air quality. Of course, the best solution is to completely replace it with an electric boiler or heat pump. By using alternative heat sources, we can further reduce CO2. All you need to do is use a photovoltaic installation to power them.
What should you consider when selecting a photovoltaic installation for a heat pump?
We usually adjust the power of the photovoltaic installation to meet basic energy needs. In the next step, it should protect domestic hot water. Only then can it protect heating purposes. However, we must plan the installation very well, because after securing the energy intended for powering everyday appliances and heating water, there may not be enough energy to heat the house and it will be taken 100% from the power plant. If, after using the energy for basic energy needs and water heating, there is e.g. 4,000 kWh left for use in the installation and we connect a heating source using 6,000 kWh, then we will already know the difference, which we will buy in full from the energy company. However, if we add a heat pump as a heat source, which consumes 1 kW of electricity and produces 3.5 kW of thermal energy, we see much greater economics. The most important thing is to select a photovoltaic installation that meets your basic needs, hot water and heat source. If we perform these calculations correctly, we will be able to enjoy low bills throughout the year, regardless of whether we connect a heat pump or an electric boiler to the installation.
What are the differences between a heat pump and an electric boiler combined with a photovoltaic installation?
The main advantage of an electric boiler is its favorable price. If the investor incurs costs related to the construction of a photovoltaic installation, then an economical solution will be to connect it with a not very expensive electric boiler. However, when a heat pump is added to such an installation, the installation cost may range from PLN 30,000 to PLN 40,000. zlotys, then the investment becomes quite expensive. However, the heat pump has the main advantage compared to the boiler - it consumes up to 3-4 times less electricity. So, in fact, at the investment planning stage you should decide, preferably with the help of a specialist, which solution will be the best.
So how to properly match the heat pump to the building?
Every building, old and new, has a specific energy demand for thermal energy. If the building has a demand of 8 kW, the pump should have a similar power. If the pump is oversized, i.e. the parameters are much higher than the building's demand, then it will certainly work properly on frosty days. However, when the temperature increases, the pump will enter the so-called timing. To sum up, it will quickly fill the heat gaps in the building and then turn off. As soon as the temperature in the building drops, the pump will repeat this process. In the ultimate
settlement will consume a lot of energy. However, if the pump power is lower than the building's heat demand, then on frosty days the pump will have to turn on an additional peak heat source in the form of an electric heater. Then energy consumption will increase.
What characteristics must a hot water exchanger match to a heat pump have?
Of course, this is a very important question. The most important parameter of an exchanger adapted to a heat pump is the large surface of the coil. We match it to the pump power. Approximately 0.25 m² of coil is assumed for each kilowatt of pump power. In addition, the exchanger tank itself should have a capacity of 200-300 liters.