Put the heat on system efficiency
Five of the best things you can do to make sure you’re getting value out of the energy you put into process heat.
- Reduce demand. Look for opportunities where steam is being wasted or overused.
- Check temperatures and pressures. Make sure they’re appropriate for the end use – the lower they are, the lower the losses.
- Spread the load. If you can keep the load at or near optimal setting point, you’ll get better efficiency.
- Minimise distribution losses. Are there remote end users that could be better serviced by a small, dedicated, heat source?
- Look for heat storage opportunities. This can help to spread the load and improve efficiency.
- Use energy efficient end-user equipment. Every unit of energy you save is a win.
New systems and upgrades – lock in the savings
Opportunities with temperature
- Make sure the temperature of the transfer fluid is appropriate to the end use and demand. The lower the temperature, the lower the energy losses.
- Heating at temperatures below 100°C can be achieved with heat pumps, which are much more energy efficient and low carbon than boilers. They’re also more economic, providing they are correctly sized.
- If only a subset of your energy end use requires a higher temperature, servicing it with dedicated heat production may improve the overall efficiency of your process.
Using waste heat
- Look for hot waste streams exiting from your system. Flue gas, air, water or even steam can be reused if there is enough volume at the right temperature.
- Think about whether waste heat could be used to pre-heat any entering streams. Temperature match is key. You can address differences in timing with storage.
Options for distributed or centralised systems
You can either generate heat in one central location and distribute it to all the end uses, or generate heat with a number of smaller systems located close to where the heat is needed.
These factors will have a bearing on which option is best for your business:
- Location of heat end uses – whether they’re in one building or many.
- How far the heat needs to be distributed – longer distances mean greater thermal losses.
- How much heat you need at each location.
- The space available to locate distributed boilers.
- The load profile during the day/season for each end-user.
- Needs and opportunities to install thermal storage tanks.