Heat recovery for screw compressors
Put the waste heat from your compressor to good use
Operating screw compressors generates a large amount of heat that can be used cost-effectively.
By consistently implementing heat recovery concepts, up to 94% of the electrical energy used can be recovered as heat. This protects the environment and leads to considerable energy cost savings with short payback periods.
Recovery
up to 94 %
Water temperature
up to 65 °C
Systems
internal and external
Retrofitting
possible
Good air quality and operational reliability
One way of recovering heat is to use the heat radiated by the compressor. This can be used for heating in the form of warm air via exhaust air ducts.
With heat recovery using an oil/water heat exchanger, on the other hand, process or heating water is heated to a temperature of up to 65°C. RENNER offers two systems for this, which can also be retrofitted into existing installations and networks:
The integrated plate heat exchanger is installed in the screw compressor and connected directly to the oil circuit, so no additional floor space is required. Thanks to the additional water connections, it can be connected quickly and easily to the in-house water network.
This solution is available for the following compressors:
RS-PRO 2-11.0 – 18.5
RS 18.5 – 1-30.0
RS-PRO 2-30.0 – 55.0
RS 55.0 – 250
The external plate heat exchanger is housed in a separate casing. With its compact dimensions and prepared connections, it takes up little space and can be integrated quickly and easily into the existing system. No external energy is required for operation.
The external plate heat exchanger is suitable for the following compressors:
RS-PRO 7.5 – 18.5
RS 18.5 – 1-30.0
RS-PRO 2-30.0 – 55.0
RS 55.0 – 132
For sensitive areas and on request, double-walled safety heat exchangers are also available for both systems. Other temperature ranges are possible on request.
For sensitive areas and on request, double-walled safety heat exchangers are also available for both systems. Other temperature ranges are possible on request.
The annual savings potential can be calculated using the following formula:
Usable energy (kW) x hours (h) x heating oil price (€)
_________________________________________________________________
Calorific value of the oil (kWh/l) x heating efficiency
Annual savings potential when using a plate heat exchanger in the RENNER RS-PRO 15.0:
13.18 kW x 1,680 h x €0.8
______________________________ = 2,113.58 euros
9.86 kWh/l x 0.85
Advantages:
- Considerable cost savings through free use of the heat energy generated
- Short payback periods thanks to BAFA funding and energy cost savings
- Small footprint thanks to compact design or integration within the units
- Simple installation thanks to ready-to-connect components
- Protects the environment, as the energy generated is recovered and put to good use
Internal and external heat recovery
Internal heat recovery
External heat recovery
Frequently asked questions
How much energy can be recovered from a screw compressor?
With consistent implementation, up to 94 % of the electrical energy used, in the form of heat.
How can I use the waste heat?
Either as warm air, routed through exhaust air ducts for heating. Or via an oil/water heat exchanger that heats process or heating water.
How hot does the water get?
Up to 65 °C with an oil/water heat exchanger. Other temperature ranges are possible on request.
What is the difference between internal and external heat recovery?
The internal plate heat exchanger is installed in the compressor and connected directly to the oil circuit, so it needs no additional space. The external one sits in a separate, compact casing and works without external energy.
Can heat recovery be retrofitted?
Yes. Both systems can also be retrofitted into existing installations and networks; the connections are prepared.
Which compressors are the heat exchangers available for?
For the RENNER RS-PRO and RS series in various power classes. We will be happy to work out with you which solution suits your compressor.
Is there a solution for sensitive areas?
Yes. Double-walled safety heat exchangers are available for both systems.
How do I calculate the savings potential?
Usable energy in kW times operating hours times the heating oil price, divided by the calorific value of the oil in kWh/l times the heating efficiency. The result is the annual saving on heating oil in monetary terms.
Is the investment worthwhile?
The waste heat is generated anyway and is used free of charge. This considerably reduces energy costs, and payback periods are short.
Who can help me choose the right heat recovery system?
We can. The right model depends on compressor output, consumption, running time and space, and we will advise you on this. Call us or write to us.
Which heat recovery system suits your compressors?
There are various heat exchanger models, which vary according to compressor output, consumption, running hours and available space. Let us advise you to find the optimum model for your needs.
