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The ÐÇ¿Õ´«Ã½ Research
Establishment estimates that 90% of heating and ventilation control systems in buildings are inadequate, and that this is costing UK industry £500m a year in additional energy costs.

AEC, an energy specialist, believes this is down to poor boiler controls and that most commercial buildings could save at least 20% on their heating bills. Using the simple measures below, we helped the Hind Grove estate in Tower Hamlets reduce its annual energy costs from £111,000 to £50,000, and cut the fuel bills of about 430 homes.

Get to know your boiler
The first step towards reducing heating bills is to investigate the firing patterns of the boilers – when they start up, reach peak temperature and turn off. You can work out how efficiently heat is being used by logging the temperature in your boiler room at one-minute intervals over 24 hours. An adequate building management system will be able to provide this information, or data-logging equipment can be attached to key points on the plant.

This provides a picture of the building's behaviour and will allow you to identify the demand for energy and match the supply to it. Although this may sound like no more than common sense, it is surprising how few buildings are run this way despite the huge savings that can be reaped.

Heat and efficiency
For maximum energy efficiency, your heating plant must be run according to building efficiency rather than boiler efficiency.

These measures helped one estate reduce its annual energy costs by £61,000

Boiler efficiency means that water is stored at the optimum temperature for the transference of heat from the burner flame to the water, usually about 82°C. This doesn't take into account whether the heat is needed and so is not the most efficient way to heat a building. ÐÇ¿Õ´«Ã½ efficiency means keeping the boilers off for as long as possible while maintaining services, looking at the building's requirements as a whole. This provides the exact amount of heat required for heating and hot water.

Temperature, temperature
You could also sequence the boiler to the return temperature of the water rather than the flow temperature. Flow temperature sequencing means the boiler heats water to its internal thermostat and takes no notice of demand from the building. This means that when demand is low, water may return to the boiler at almost the same temperature as it left.

Setting the boiler to meet a target return temperature means that it heats water according to how much the building is using. The desired level can be as low as 60°C, which wastes much less energy but is still hot enough to ensure protection from Legionella bacteria.

Fire away
You should also ensure that the correct number of boilers fire to meet demand. Often, multiple boilers are firing when one would be sufficient to meet the requirement from the building.