Compressor waste heat recovery for heating – forecast over 120 MWh per year
Elister installed an automation-controlled heat recovery system in the compressor oil cooling circuit for AQ Lasertool OÜ, directing the residual heat of the 55 kW compressor into the building's heating system and domestic hot water. The system recovers an average of 10 MWh per month, with an annual forecast of over 120 MWh, resulting in significant heating cost savings and reduced CO₂ emissions.
Project challenge
Production had a constant heating need and the compressor operated daily, but the waste heat of the 55 kW unit had previously gone unused. Payback calculations showed that directing the heat into the building's heating system provides a very fast return on investment, which is why it was decided to implement the solution.
How we built the solution
We installed an automation-controlled heat recovery system into the compressor's oil cooling circuit, which optimises heat exchange and prevents the compressor from overheating. Heat energy is directed both to the domestic water and the heating water, and all parameters are adjustable.
- Automation-controlled heat recovery system
- Oil and domestic water/heating water temperature regulation using four sensors
- Built-in heat meter for accurate measurement of recovered energy
- Directable both to domestic water and the building's heating system
Result
Based on the first results, the amount of recovered energy averages 10 MWh per month. During the winter months, an even greater result is expected, as the higher temperatures of the heating system enable more efficient heat transfer due to the small temperature difference. The projected annual amount of waste heat is over 120 MWh, which means significant savings in heating costs and a reduction in CO₂.
Galerii
FAQ
Frequently asked questions
How much energy does the system recover?
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How is recovered energy measured?
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