With energy prices continuing to rise, more and more companies are looking for solutions that offer energy for free in the form of heat recovery. Free heating can help to drastically reduce gas or fuel consumption – or even eliminate it altogether – by repurposing heat rejected by the cooling process.

Cooling and heating as a single service
Traditional HVAC design approaches heating and cooling as two separate systems but enhancing one or the other can only produce limited savings in energy consumption and reduced carbon emissions. Cooling and heating loads typically overlap, however most buildings have separated chiller and boiler rooms with no interaction between the two systems.

Trane Rental’s approach is very different – we look on cooling and heating as services, not products, which means we can assess systems as a whole and look for every opportunity to save on energy use. We recognise that a combined heating and cooling approach can significantly reduce energy consumption and carbon footprint by eliminating all or part of the fossil fuel used for heating or hot water purposes.

How it works
Heat pumps use a refrigerant to absorb heat from a cold source, typically the ambient air or water. The refrigerant is then compressed, which raises its temperature, and the heat is released into the HVAC system through a heat exchanger, the condenser. Heat pumps are highly efficient. They can move heat instead of generating it, which is significantly more environmentally friendly and cost-effective, especially when compared to other heating methods that convert energy to heat with a maximum theoretical efficiency of 100%, such as burning fuel in a boiler. Heat pumps, in comparison, are three to six times more efficient.

Trane water-to-water heat pumps can provide high heating efficiencies. They deliver all the cooling capacity needed while also having the potential to deliver heating for free. The secret is just thermodynamics – chillers reject heat to the atmosphere when they cool a fluid, while heat pumps can transfer the same heat into the hot water system of the building.

This integrated cooling and heating production of a water-to-water heat pump is also the most viable choice from an economic standpoint. Energy consumption for cooling remains the same but heat is being delivered for free as a valuable by-product of the cooling process, rather than being rejected to the atmosphere.

Heat pumps are designed to be highly energy-efficient because they don't generate heat directly; instead, they move heat from one place to another. 

Retrofit options
The solution is easy to implement, and you don’t necessarily have to start from scratch with a whole new system. Heat pump modules can often be added as a retrofit option on many existing chiller systems, without compromising either performance or reliability.

At a car components manufacturer in the Czech Republic, Trane Rental Services helped the company achieve extensive five-figure savings over a period of just four months with a heating and cooling solution aimed at reducing energy costs through free heating. The company has a 30,000 square feet factory and over 1,200 employees. It had been relying on gas boilers and ageing air-cooled chillers to fulfil its substantial cooling and heating requirements. However, a year-long trial – covering just part of the factory’s overall cooling and heating needs – has proved a huge success. The local Trane Rental team supplied two different units: a Sintesis Advantage CGAF air-cooled chiller to replace an existing air-cooled chiller and a City™ RTSF water-to-water heat pump to replace an existing water-cooled chiller. The aim with the RTSF unit was to provide both cooling and free heating: 260 kW of cooling capacity at 17/12°C for the factory production line along with 300 kW of free heating – at temperatures of up to 75°C – for employee comfort in the factory’s administration building. Trane installation has drastically reduced the gas consumption in the boiler system.

In Portugal, one of Europe’s leading providers of electronics packaging wanted to replace its gas boiler with a heat pump solution that could provide free heating and energy-efficient cooling. The plant needs cooling for dehumidification during the manufacturing processes while both cooling and heating are needed for employee comfort. The company has 900 employees working at its 500,000 square foot facility. The Trane solution – using air handling units and an XStream™ RTWF water-to-water heat pump– provides all the needed cooling capacity while delivering 1750 kW of free heating. Also, the unit uses R1234ze refrigerant which has a near-zero GWP.

Conclusion
Reducing carbon emissions and cutting energy costs – these are clearly everyone’s goals at present. Trane Rental Services works closely with its customers to identify opportunities where free heating can be provided through our innovative heat pump technology. It is an easy choice, and as our many customers can testify, tremendous savings can be achieved.

Learn more about Trane heat pump systems