Today heat pumps are in common use as an environment-friendly way of heating and cooling buildings. In an energy system of the future, with priority given to making more use of renewables and boosting system efficiency, this versatile technology could well play an increasingly vital part. Using ambient heat is an important advantage of heat pumps; heat stored in outdoor air, the groundwater or the ground is raised from a lower temperature to a higher one by means of an efficient technology, making it available for space heating and supplying hot water. In the case of cooling the flow of refrigerant is reversed (active cooling). With ground-source or groundwater-source heat pumps low ground temperatures can also be exploited directly (passive cooling). Heat pump technology has considerable potential when it comes to heating and cooling efficiently via thermal grids and to making efficient use of energy in industry and commerce.
Austria’s technology road map for heat pumps
In 2016, commissioned by the Ministry for Transport, Innovation and Technology (bmvit) and the Austrian Heat Pump Association, AIT Austrian Institute of Technology and e-think drew up an Austrian road map for heat pump technology. This spotlights heat pumps’ economic potential up to 2030, and includes an R&D agenda which identifies the crucial steps to be taken and details the appropriate framework for the introduction on the market. As between the four main areas of application, “Heat pumps for residential and non-residential buildings”, “Smart electric grids and heat pumps”, “Heat pumps in thermal grids” and “Heat pumps for industrial processes”, the need for research and innovation as regards heat pump technology in Austria varies.
In the area of new buildings, residential and non-residential, the heat pump has steadily gained acceptance as a heating technology over many years. The area of renovating buildings is seen as a major market of the future with real potential. Here there are research issues of system integration and control to be tackled, particularly in the field of hybrid systems. With applications to deliver temperatures above 100°C there is a need for additional research to develop technology for heat pump units that can be integrated into industrial processes so as to minimize heat wastage.
Market situation and trends in Austria
In 2015 roughly 78,700 process-water heat pumps, 158,100 heat pumps for space heating, 4,700 air-conditioning heat pumps and several hundred industrial heat pumps were in operation in Austria. Domestic sales of heat pumps for space heating are currently going up fast; in 2015 17,451 such pumps were sold in Austria, an increase of 9.8 % on 2014. Most heat pumps for space heating are installed in new detached and semi-detached residences, where pumps in the lowest rating category are employed (up to 10 kW); in 2015 this sector grew by 21.4 %. However, heat pumps are also in use in blocks of flats and in service-sector buildings.
In the mid term the largest potential for heat pumps in space heating will be in renovating existing buildings. In this field heat pumps can also be used to dry buildings out. As regards sources of heat, there is currently a strong trend to air/water systems (for economic and structural reasons), but more use has also been made of direct-vaporization systems in recent years.