Top improvements to save costs and carbon
- Check and monitor the excess air.
- Check for insulation damage and leaks.
- In solid fuel combustion systems, check fuel is distributed evenly on the bed.
- In liquid or gaseous fuel combustion systems, check the flame patterns are correct.
- Make sure heat transfer surfaces are clean, or can be cleaned easily and often.
- Review boiler set points to minimise short cycling.
- Modify boiler sequencing to ensure the most appropriate boiler is matched to the demand.
New systems and upgrades – lock in the savings
Opportunities with fuel switching
High temperature electric heat pumps are the way to go if your temperatures needs are up to 100°C (or 120°C in some instances). They’re highly efficient, commercially available, and use New Zealand’s low carbon electricity.
For higher temperatures, the best option depends on your energy use profile.
- Biomass is a viable alternative if your energy use is relatively stable. It can replace coal or be used as a co-firing option.
- Electro-boilers may suit if you have peaking energy use. They’re convenient, low capital, low maintenance investments, with the downside of having a higher energy costs.
- Mixed options can work for energy uses with a strong regular base (provided by a biomass boiler) and some peaking (provided by an electro-boiler). This helps you find the best economic balance between capital cost and energy cost.
If flue gases are above 120°C, investigate opportunities to fit an economiser.
Pre-heating combustion air
Combustion air is low temperature, so can be pre-heated by almost any waste heat stream. Pre-heating combustion air increases your boiler efficiency.