Adjust controls to match heating, cooling and lighting use to occupancy periods and to ensure service levels meet the needs of occupants ie avoid overheating, overcooling and excessive lighting levels.

Match time switch settings to occupancy to reduce plant operational time.

Establish responsibility for control setting, review and adjustment eg for BST-GMT switch.

Concentrate out-of-hours occupancy in one zone and run plant in these areas only.

Switch off lights and equipment when leaving a zone. Switch off lights when natural day light alone is sufficient.

Close all windows and doors when possible during the heating season.

Discourage supplementary electrical space heating appliances.

Use window shading devices such as blinds during summer to minimise air conditioning loads. Close window shading device during the heating season and when dark outside to minimise radiation losses.

Switch off heat generating equipment when not in use during the cooling season.

Maintain the building fabric to avoid excessive infiltration and minimise heat losses.

Maintain efficient operation of the mechanical ventilation system through regular cleaning and balancing.

Regularly clean and maintain all plant and distribution systems to ensure operational efficiency is kept high.

Raise chilled water temperatures, often water is needlessly chilled to low temperatures effectively providing unnecessary de-humidification.

Low-cost options

Typically requiring investment of less than 5% of the annual energy bill and payback within 3-5 years.

Replace existing lamps/luminaries with high-efficiency lamps/luminaries.

Use luminaries with efficient reflectors; this allows fewer lamps or luminaries to be used to produce a given illuminance.

Install automatic lighting control using time switches/ occupancy sensors/PSALI.

Improve HVAC control using compensators, thermostatically controlled zone and radiator valves.

Lag pipes, boilers, storage tanks, valves, insulating ductwork

Install power factor correction equipment.

Install draught stripping on doors and windows or replace if worn; typically gives a payback of under two years. Seal gaps between window frames and walls. Seal building openings at service penetrations.

Insulate wall cavities, roof voids and floors to minimise heat losses. Paybacks within 3-5years.

Install enthalpy sensors and controls to detect the cooling capacity of the external air and then modulate dampers to draw in more air than the basic fresh air requirement to provide free cooling.

Use night time air temperatures and the thermal capacity of the building to reduce daytime cooling requirements.

Capital-cost options

Typically when no or low cost-schemes have been implemented OR when major plant changes are required at end-of-life. The economics of these schemes improve when implemented as part of normal refurbishment work and payback can be less than 5 years.

Replace standard glow-switch starters with electronic starters, soft starting extends the economic life of the fluorescent tube, reducing maintenance costs. Energy savings can be 15-20%, with payback periods of 5-10 years.

Installation of a building energy management system top control and monitor energy usage.

Install double glazing to minimise heat losses.

Reduce solar gains through coated glasses, blinds or external shading.

Link heating and ventilation controls to occupancy sensors.

Replace boilers with condensing type. Install new burners to improve combustion and therefore conversion efficiency.

Install on site co-generation/ tri-generation, heat pumps or renewable energy systems

Install heat recovery devices on ventilation plant.

Reference: Energy efficiency in buildings, CIBSE Guide F, 1998

Energy Efficiency

Social considerations