The Remarkable Efficiency Of Heat Pumps, Explained

Heat pumps use electricity to compress a refrigerant, raising its temperature. IEA

Heat pumps have only been a passing reference occasionally in these pages, but today they are the focus, thanks to Paul Hockenos in Yale e360:

In Europe’s Clean Energy Transition, Industry Turns to Heat Pumps

With soaring gas prices due to the Ukraine war and the EU’s push to cut emissions, European industries are increasingly switching to high-temperature, high-efficiency heat pumps. Combined with the boom in residential use, the EU is now hoping for a heat pump revolution.

An industrial heat pump at the Mars Confectionery in Veghel, the Netherlands. GEA

The Wienerberger brickworks in Uttendorf, Austria, in the Tyrolean Alps, has always required a steady stream of 90 degree C (194 degree F) heat to dry its construction blocks. This process would have been an expensive proposition for the company after Russia cut gas exports to Europe, as it was for most of Europe’s energy-intensive construction industry. But four years ago, Wienerberger — the largest brick producer in the world — made an investment in the future that is now paying off: it replaced Uttendorf’s gas-fired boiler with an industrial-scale heat pump, which whittles the factory’s energy bill by around 425,00 euros a year.

For decades, electric heat pumps have been used in European homes and other buildings for heating and cooling, but they’ve never gained much traction in manufacturing, which has far higher energy demands for producing hot water and steam. And because fossil fuels had long been relatively cheap, industries had little incentive to replace gas- and oil-powered systems with greener equipment. Now, with the development of heat pumps that can deliver temperatures up to 160 degrees C (320 degrees F) at a fraction of the price of gas boilers, and with gas prices skyrocketing due to the war in Ukraine, that calculus is being turned on its head. Many European businesses are rethinking their energy sources while also slashing their greenhouse gas emissions, an EU requirement. European industry is responsible for more than a quarter of the bloc’s greenhouse gases.

To meet its lofty energy goals and break its dependence on Russian gas, the EU is counting on nothing less than a heat pump revolution. In many countries, sales of heat pumps — primarily for residential use — doubled in the first half of 2022. In Germany, Europe’s largest consumer of Russian gas, demand jumped 52 percent last year, while growth across the EU in 2021 was 35 percent. Meanwhile, a somewhat less-heralded transition to heat pumps for manufacturing is gathering speed. Wienerberger, for instance, is now installing similar pumps at its brick foundries in the Netherlands, the U.K., Poland, Romania, and elsewhere in Austria.

“Five years ago most companies knew next to nothing about heat pumps,” says Veronika Wilk, a senior research engineer at the Austrian Institute of Technology. “Now companies are aware of them, and ever more heat pumps are installed in industry.”

A compression heat pump can both warm and cool air. In the winter, it raises indoor temperatures by removing heat from water, from deep in the earth, or from outdoor air, then ratchets up its temperature using a small amount of electricity and moves that air indoors. Even air as cold as -12 degrees C (10 degrees F) contains sufficient energy for a heat pump to extract and boost its temperature. In the summer, electric heat pumps lower indoor temperatures by removing heat from interior air and shunting it outside. Absorption heat pumps run not with electricity but with a heat source, which could be natural gas but could also be solar-heated water or even waste heat from data centers or sewers. They bring this heat up to a “useful” temperature, then deliver it as either warm air or hot water.

Read the whole article here.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s