Heat Pumps to Cut CO2 Emissions
Nearly everybody now has a heat pump in their house. This being better known as a refrigerator. The idea being that when a gas is pressurised it changes state into a liquid and this process causes heat. When it allowed to be in a less pressurised environment it will change back to a gas and while condensing will cool the surrounding area, i.e. the refrigerator.
If this process is used in reverse then the ground or a nearby river could be cooled and the heat generated could be used as space heating, for a house or office.
The CO2 emissions reduction potential of 6% will increase in the near future, because both heat pumps and power plants are becoming more efficient as a result of technology developments. While the efficiency of a fossil fuel boiler can never be higher than 100%, the theoretical heat output of a space heating pump is approximately 14 times the energy input. Heat pump technologies can be used in both residential and industrial solutions, competing with fossil fuel boilers and direct electric heating. They can be used just for heating , but can also simultaneously produce both heating and cooling, useful for different parts of a building or in different seasons.
Building applications
In many countries, space heating and cooling are two vital elements to create a comfortable working atmosphere. In the Netherlands, the 26,000m2 Anova office building is heated and cooled by a ground coupled heat pump which supplies and extracts heat from an underground thermal storage, an aquifer. This installation saves 7% on electricity and 84% on natural gas compared to a base line installation, and CO2 emissions drop by 52%.
In central and northern Europe with a moderate to cold climate, residential heating-only heat pumps provide an energy-efficient way of heating at low emission levels. Many of these heat pumps extract (solar) heat from the ground. In Switzerland, for example, replacing an oil fired boiler by an electric heat pump reduces CO2 emissions by 98%. This high figure is the result of a nearly CO2 free electricity production.
Industrial applications
In many industrial processes, heat pumps are applied to recover process waste heat. They are used in dehumidification, distillation and evaporation processes, but also for water heating and combined heating and cooling, many opportunities in the food and chemical industries. One of the largest heat pump installations in the world is integrated in a propylene/propane distillation process at the Shell site, Pernis, in the Netherlands. This heat pump saves 37 million m3 gas annually, and cuts COO emissions by 90 thousand tonnes.
Further savings potentialTo emphasise the potential which heat pumps offer, the IEA Heat Pump Centre carried out a large scale assessment of the global environmental benefits of using heat pumps. This analysis concludes that there is a large potential for extending the present environmental advantage of heat pumps over conventional heating systems. This potential is an invitation waiting for realisation, through R&D, the support of governments and utilities, and through market transformations.
More information
from the IEA Heat Pump Centre at Novem in Sittard. TEL: +31-46-420 2236
E-MAIL: hpc@heatpumpcentre.org URL: www.heatpumpcentre.org