Saving Energy in Offices

Office energy saving starts with a benchmark, then uses measured proof to find avoidable use in lighting, HVAC, IT, kitchen equipment and out-of-hours loads.

Use this page for

• Finding where electricity, heating fuel and water are being used.
• Checking night, weekend and lunch-period consumption.
• Measuring plug-in equipment and office appliances.
• Setting practical savings targets and proving progress.

Recommended loggers

Product	Logger	Best fit	Measures
	EC-7VAR-RS Electrocorder EC-7VAR-RS Three Phase Voltage, Current & Power Factor Recorder	Best for larger offices with three-phase supplies where full power and energy behaviour matters.	Three-phase voltage, current, power factor and energy.
	CT-3A-RS Electrocorder CT-3A-RS Three Phase Current Logger (60A/200A or 60A/400A)	Useful for longer current-only load surveys on three-phase feeders.	Three-phase current only.
	EC-2VA Electrocorder EC-2VA Power Logger and Energy Recorder	Best for single-phase circuits or equipment where voltage, current and energy are all needed.	Single-phase voltage, current, power and energy.
	CT-2VA Electrocorder CT-2VA Power and Energy Recorder	Best for single-phase current-derived power and energy checks where voltage measurement is not required.	Single-phase current-derived power and energy.
	AL-2VA Electrocorder AL-2VA Energy Logger for Domestic and Light Commercial Appliances	Best for plug-in office equipment, appliances and socket-level energy checks.	Single appliance or socket-level power and energy.

Start with a benchmark

There are many ways to save energy in an office, and many cost little to implement. Start by assessing the present consumption. The first purpose is not to decide whether energy reduction is possible, but to create a benchmark that can be compared against later.

Read meters for electricity, gas, heating oil, petrol, diesel and water. Bills may arrive monthly or quarterly, but regular meter readings give a better breakdown of when energy is being used.

For a short office survey, read the meter first thing in the morning, at the start and end of lunch, and at the end of the working day. Compare Friday evening with Monday morning to understand how much energy is used when the office is closed.

Benchmark office energy use

For an office that does not manufacture a physical product, useful ratios include kWh per employee per year and kWh per m2 per year. The original Acksen office example used the following figures:

• 1,500 kWh per employee per annum.
• 94 kWh per m2 per annum.
• 10 kWh per widget per annum.

These ratios help with year-on-year comparison, but they should be treated carefully. A kWh per employee figure assumes that employees, working patterns and the type of work are comparable.

If direct comparison with competitors is difficult, compare with similar non-competitive businesses, neighbours or partners. Even approximate comparison can show whether energy use is unusually high.

Education and behaviour

Ask staff to turn off lights when leaving an empty office, avoid leaving PCs running through lunch, and switch equipment off at night. A PC left on through a one-hour lunch break may waste around 12% of its daily running time. Energy reduction can also be made part of staff incentives or internal targets.

Turn off lights, PCs, radiators and heaters when rooms are vacant. Put named people in charge of checking empty rooms and out-of-hours use.

Lighting

Check that lighting meets legal and practical requirements without over-lighting. If there is too much light, remove lamps or tubes. Upgrade inefficient lighting, open blinds where natural light is useful, and replace incandescent or halogen lamps with efficient alternatives.

Thermostatic control and HVAC

Heating and cooling settings should be controlled by authorised people. If particular staff need warmer or cooler conditions, it may be better to move them closer to or further from heating and cooling sources rather than changing the whole office.

Check that HVAC is not running on Saturdays, Sundays or holidays. This is a common problem because nobody is present to notice it. Personal fan heaters should be discouraged because electricity is often the most expensive form of heating and portable heaters can be left on.

A voltage or duty-cycle logger can be used to analyse when a pump, fan, oil heating system or gas heating system is running. The fan or pump electricity may be small, but the associated heating fuel can be very significant. Logging can show whether heating runs when the building is empty or whether frost protection is set too high, such as 15C instead of 5C.

Review bills and measured data

Review electricity, gas, heating oil, petrol, diesel and water bills to understand where energy sits in overall business spending. A simple pie chart of major company purchases can show whether energy cost is large enough to justify a deeper audit.

Investing in a data recorder gives measured proof rather than relying only on equipment ratings. The AL-2VA is suitable for office and home equipment and can show the actual energy profile of individual items. In larger premises with a three-phase supply, a current logger can record a rough energy profile over a week so that theoretical estimates can be compared with real results.

Practical office checks

Vending machines without perishables can often be switched off at night and weekends, or controlled by a 5/2 time switch. Toilets can use IR lighting sensors, and hand-dryer sensors and timers should be checked. In kitchens, avoid overfilling kettles, put coffee makers on time switches, and coordinate breaks so one kettle boil serves several people.

Targets, controls and responsibility

A realistic starting target may be a 5% or 10% reduction over 6 to 12 months. The sooner practical changes are implemented, the sooner savings begin. Monitor progress against the original benchmark.

Use time clocks and time switches to enforce a use-envelope for non-critical equipment.

If cleaners enter the site early and turn on all lights, HVAC, escalators or vending machines, they may be spending a considerable amount of money on your behalf before the office is occupied. Check up on out-of-hours operation and appoint one or more responsible people to analyse and control energy spending.

Related guides and products

• Energy Audit Loggers: for energy audits, load profiles, peak demand and before/after savings proof.
• Load Survey and Current Loggers: for feeder checks, current logging, load surveys and capacity planning.
• All application guides: choose an Electrocorder by the job or problem you need to investigate.

Relevant products:

• EC-7VAR-RS: Electrocorder EC-7VAR-RS Three Phase Voltage, Current & Power Factor Recorder.
• CT-3A-RS: Electrocorder CT-3A-RS Three Phase Current Logger (60A/200A or 60A/400A).
• EC-2VA: Electrocorder EC-2VA Power Logger and Energy Recorder.
• CT-2VA: Electrocorder CT-2VA Power and Energy Recorder.
• AL-2VA: Electrocorder AL-2VA Energy Logger for Domestic and Light Commercial Appliances.