The preference of heat pumps in District Energy has to do with many benefits and the fact that this technology is very energy efficient. Most industries are striving to keep energy consumption as low as possible, which is understandable given the rising energy costs.
Heat pumps transfer heat from a lower temperature system to a higher temperature one, thanks to the refrigeration cycle that they perform in between.
Heat is taken from a heat source, where normally the temperature is not controlled. The heat is then transferred to the consumer at a suitable and controlled temperature, which will depend on the application. Heat pumps benefits are quite a lot, and they can be used in a wide range of fields, from commercial to industrial size.
Heat pumps are used as an alternative to traditional boilers and electric heaters to produce heat energy, as the efficiencies that they can achieve are higher when there is a suitable heat source available.
What are the major benefits of heat pumps?
The main benefits of a heat pump are focus on the environment positive impact we would achieve reducing energy consumption at the same time that we are improving the CO2 footprint of the district energy overall system. The combination of different heating technologies will improve the decarbonization objective in the short term.
Resilience: fossil fuels dependence reduction:
If the heating sector uses more efficient heating systems based on low cost heat sources connected to low cost renewable energies, the final system balance will help to make resilient the whole energy market. The fuel import reduction will increase the energy independence of these countries, obtaining more financial resources to increase the industrial competitiveness and to promote the ecologic transition.
Circular economy contribution
New District Heating developments promote the use of waste heat coming from wastewater treatment plants or heat surplus from industrial market or data centers as the preferred heat source for heat pumps. One of the fundamentals of the circular economy is based on promoting the use of locally produced renewable energies, managing consumption and providing storage capacities to the regional energy system on demand.
Renewable energies contribution:
The influence of heat pumps on renewable electricity integration can be examined with several approaches. The influence on the use of heat pumps is analyzed under the assumption of a certain share of renewable energies in the electrical generation. Alternatively, the impact of renewable electrical generation is analyzed by assuming a high share of heat pump technology in heat generation. The expansion of renewable energies and the use of heat pumps are mutually influential, and therefore it is necessary to model their interdependencies when analyzing the sector coupling.
CO2 footprint and refrigerant green gas:
Selecting an environmentally friendly refrigerant is also important in order to receive a higher quantity of LEED points to achieve a higher certification level. The refrigerant used must have a very low Global Warming Potential and Ozone Depletion Potential. Given its favorable properties, natural refrigerants remain as the preferred refrigerants for efficiency and environmental reasons and they are expected to stay so indefinitely. The new synthetic HFOs have been approved as a strong solution, using hydrocarbon mixes that in some cases can obtain an ultra-low GWP, lower than 10.
Gas regulation compliance
The European market and others economics areas are regulating refrigeration and heating market by one of the most ambitious statement for CO2 emission reduction, reducing the use of HFC with high GWP for cooling or heating installations. New heat pump designs will manage these limitations inside the EU using natural refrigerants (Ammonia, CO2, hydrocarbons) and HFO with low GWP (<10), maintaining an optimal efficiency criteria.
These are the main heat pumps benefits for DH. But heat pump design expertise will permit a larger range of efficient systems depending on the project requirements, heat sources available, renewable energies coupling, local regulations and temperature supply to the network.
What are the key success factor on the heat pump design that will improve the global efficiency of the district energy of the future.