Every rational person recognises that global warming (or, more accurately, global heating) is an existential threat to the planet.

A series of recent meteorological disasters around the world – including extreme heat and strong winds resulting in huge forest fires and dramatic flooding caused by intense rainfall – are a stark warning that all is not well with our planet’s biosphere.

To mitigate the dangers exposed by the climate emergency, we must limit global warming to 1.5°C, the threshold that the Intergovernmental Panel for Climate Change suggests is safe.

For this to happen, we need to achieve climate neutrality by reducing greenhouse gas emissions to zero. The question is: How? The answer is ‘clean’ electricity generated by non-polluting renewable energy sources such as geothermal, solar, tidal, and wind power.

But a sustainable path to climate neutrality involves more than electrification alone; it also demands efficient cooling and heating technology. Heat accounts for almost half of the UK’s total energy consumption and around 25% of greenhouse gas emissions. This makes heating a prime target for efficiency savings.

The link between energy efficient heating & cooling

One of the best ways to improve heating efficiency is, ironically, to confront the energy issues created by cooling or, more specifically, the waste heat generated in its production, much of which is simply released into the surrounding air.

Heat recovery – the process of collecting and re-using heat that would normally be lost – is a powerful weapon in the energy efficiency armoury because it makes perfect sense both economically and ecologically.

Markus Enzensperger, a sales engineer at Engie Refrigeration, explains the value of heat recovery systems: “Heat recovery is more than just hot air: over the service life of a system, even minor energy savings can lower operating costs by several hundred thousand euros.

“At the same time, saving energy always means avoiding carbon emissions. The actual reduction in CO2 depends on the proportion of heat recovery. Companies can thus considerably improve the sustainability of their buildings and production chain.”

But how can the full potential of waste heat be tapped? The answer is to interweave cooling and heating. A great example of heat recovery technology that can achieve this can be found in Engie Refrigeration’s air-cooled and water-cooled Quantum series chillers, both of which have a heat recovery option that makes the waste heat generated by the cooling process usable for heating demands.

This saves users investment costs for additional heat generation systems and, at the same time, increases the overall efficiency of the chiller equipment.

Benefits for all

It is not only operators who benefit from heat recovery: if there is no acute demand for heat among those responsible, there is also the option of passing on the waste heat to other companies or to neighbourhoods and communities. In other words, it results in holistic solutions that benefit all involved parties both economically and ecologically.

The Quantum chiller with heat recovery possesses several properties that distinguish it from a conventional device. With a traditional heat pump, for example, the consumer decides the heat load he or she requires, and this determines the thermal output and the operation of the compressors. The machine is therefore said to be ‘heat controlled’.

With a refrigerating machine with heat recovery, on the other hand, it is only the demand that the operator places on the refrigerating capacity that matters. The machine is said to be ‘cold led’ but, unlike a pure refrigeration machine, the Quantum makes full use of the energy absorbed from the refrigerant and the electrical energy of the compressors in the form of heat.

This is achieved by transferring it to a hot water network. The higher the cooling capacity, the greater the proportion of waste heat that’s available for subsequent heating processes. In this way, the technology makes full use of the heat recovery process.

However, it is not without technical challenges. In many industries, for example, the demand for cooling varies throughout the year. And, if users don’t need cooling in the winter months, chillers with heat recovery are unable to provide heat since there will be no release of waste heat without a cold supply.

Geothermal field

Thankfully, this is a challenge to which Engie Refrigeration has risen. The company’s engineering experts have worked on an application to compensate for the inverse development of the cooling demand over the course of the year employing a geothermal field. This is used as a regenerative heat source in winter, which is achieved by extracting heat from the ground.

The Quantum air-cooled and oil-free chiller in combination with optional heat recovery brings this to a higher temperature and thus makes it usable for heating. In order to prevent the ground from cooling down too much, the Quantum feeds the waste heat from the cooling process back into the geothermal field in summer.

This ensures the supply of cooling and heating throughout the year for a variety of industries including  data centres, the chemical and pharmaceutical sectors, and process cooling in industry.

Improve efficiency, reduce costs

As well as the overall efficiency of the chiller being improved by using the waste heat from the refrigeration process, Quantum chillers with heat recovery also save money because they lower investment costs for additional heat-generating subsections or even make them entirely unnecessary.

The Quantum range with heat recovery, which covers temperatures between 3 and 57°C, is is particularly a versatile technology. For example, it is possible to install hydraulic decoupling on the heat side or to pass on the surplus cold and heat to district cooling and heating networks.

All Quantum models feature outstanding efficiency, exceptional cooling performance, convenient control systems, and first-rate serviceability. Their sustainable design uses the minimum of refrigerants, and they are light and compact due to a sophisticated modular design.

For more information about Klima-Therm’s industry-leading range of chillers, visit: Industrial, Air & Water-Cooled, Absorption Chillers