International News
USING HEATING TO COOL ROOMS
By Fraunhofer Institute for Building Physics
Climate change is causing a persistent increase in the number of hot summer days . Offices and homes are getting hotter , and the nights bring little respite from the heat .
Against this backdrop , a significant increase in new cooling system installations is anticipated , which in turn will give rise to increased energy consumption . One potential cost-effective alternative is to use existing heating systems .
According to an analysis by the Fraunhofer Institute for Building Physics IBP , the heat pumps in these systems can be reverse operated to provide effective cooling .
Global energy consumption from air conditioning systems continues to rise . According to information from the International Energy Agency ( IEA ), the total energy used to cool residential and office buildings in 2016 was around 2000 terawatt hours . That is an estimated 10 % of the world ’ s total power consumption .
This amount could triple by 2050 : By then , ten air conditioning systems will be sold every second . In Germany , experts expect energy consumption for cooling residential buildings to double over the next 20 years . For non-residential buildings , the German Environment Agency expects an increase of 25 %.
How can this expected surge in new cooling system installations be prevented ? This is the issue being addressed by a team of researchers at Fraunhofer IBP . “ In existing buildings , if a heat pump – the heat generator – that is already installed can be reverse operated to provide air conditioning , the same system that is already being used for heating could be used for cooling as well ,” says Sabine Giglmeier , a scientist at Fraunhofer IBP . This would remove the need to purchase new cooling systems and save energy .
ASSESSMENT OF THE POTENTIAL OF RADIATORS AND UNDER-FLOOR HEATING SYSTEMS To assess the extent to which this technology can be used to avoid overheating in summer , the engineer and her team assessed the potential of two heating systems : They investigated whether radiators and under-floor heating systems – heat distributors – could replace the air conditioning units that are often used in existing buildings . These units dissipate their waste heat via a tube through the window or an opening in the wall .
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RACA Journal I October 2021 www . hvacronline . co . za