Energy monitoring for business: how to track use, find waste and use smart controls

Most small businesses only look at energy when the bill arrives, by which time the waste has already happened. Energy monitoring simply means measuring usage often enough to spot problems: lights left on, a fridge struggling, a heating timer set wrongly. It can be as simple as a monthly meter reading in a spreadsheet, or as detailed as live data from sub-meters. This page explains the options and how to choose.

Why monitor?

• Find out-of-hours waste. Government guidance says nearly half of business electricity use happens outside standard operating hours. Monitoring shows how much of that is yours.
• Catch faults early. A sudden jump in overnight use can mean a failing compressor or a switch left on.
• Prove savings. After an upgrade you can see whether the saving was real.
• Avoid estimated bills. Regular actual readings stop you paying on guesses; see estimated business energy bills.

Level 1: read your meter

The cheapest method is a regular reading from your own meter. Weekly is ideal; monthly is the minimum. Write the date, time and reading in a sheet and subtract the previous reading to get use. Do one reading at close of business on Friday and another at opening on Monday to see weekend use. Our guide to submitting a business meter reading explains how to read your meter and send it to your supplier. If your gas meter shows cubic metres or hundreds of cubic feet, convert with the gas units to kWh converter.

Level 2: smart and half-hourly data

If you have a smart or half-hourly meter, your supplier may offer an online portal showing usage in half-hour blocks. That is rich data for free. Learn more in half-hourly meters explained and business smart meters. Look for the baseload (the lowest overnight demand) and for peaks that coincide with equipment start-up. The industry is moving every electricity meter towards half-hourly settlement, see market-wide half-hourly settlement, which should make more data available over time. Rules for non-domestic smart meters are set to change from 2027, with new fixed-term contracts needing smart-meter terms from 1 September 2027, according to the government's collection page.

Level 3: plug-in monitors and sub-meters

• Plug-in energy meters show how much a single appliance uses. Cheap and ideal for fridges, freezers, hot-water boilers and equipment you suspect.
• Clip-on current sensors fit in a distribution board (installed by an electrician) and show whole-building or circuit-level use live on a screen or app.
• Sub-meters measure specific areas, such as a kitchen, a tenant's unit or a separate workshop. They are useful where costs are shared. If you are a landlord, note the rules about charging tenants; see can landlords resell energy to tenants.

What to look for in the data

• Baseload creep. If the overnight minimum rises month by month, something new is staying on or something is failing.
• Morning spikes. A big jump when everything starts together can raise your peak demand; staggering start-up can help on half-hourly sites that pay capacity-related charges, see supply capacity and kVA charges.
• Weather link. Gas use should rise when it is colder. If it doesn't track the weather, controls may be at fault.
• Weekend and holiday patterns. Use should drop clearly when you are shut. If it doesn't, find out why.

Write down a simple target, such as cutting overnight baseload by 10% in three months, and recheck. Small, measured goals are easier to keep than a vague aim to save energy, and a written record helps you show a landlord, accountant or lender what changed and when.

Level 4: smart controls

Monitoring tells you what's happening; controls make changes happen. Examples include smart thermostats and zoned heating, timers and occupancy sensors on lights, smart plugs for equipment with a schedule, and automatic shutdown of kit overnight. Government guidance lists smart thermostats and lighting timers as longer-term options. Use products from reliable sources such as the government's Energy Technology List and make sure controls work with your existing equipment. For heating specifically, read business heating efficiency.

Worked example: sizing out-of-hours waste

A shop reads its electricity meter at 6pm on Friday (reading 48,200) and at 8am on Monday (reading 48,630).

• Use: 48,630 - 48,200 = 430 kWh.
• Hours: Friday 6pm to Monday 8am = 62 hours.
• Average load: 430 / 62 = 6.94 kWh per hour, or about 6.9 kW.

Fridges and alarms might explain 2 kW (an assumption). That leaves around 4.9 kW running unnecessarily. If 4 kW of it could be switched off for 5,000 hours a year (nights and weekends), the saving is 4 x 5,000 = 20,000 kWh. At 27.2p/kWh that is £5,440. Even a quarter of that, £1,360, would justify a few hours of detective work. (The meter readings and loads are made up for illustration; 27.2p is Moneysupermarket Business's October 2026 average small-business fixed rate, used as an indicative price.)

Find the culprits by switching off one circuit at a time at the fuse board and re-reading the meter. Or use a plug-in monitor on suspect equipment.

Choosing a system

• Match the effort to the bill. Get a price for the kit, installation and any subscription, then compare it with a realistic saving. As a rule of thumb, if the system would take more than a few years of savings to pay back, start with meter readings and a plug-in monitor instead.
• Check who can see the data. Make sure you own it and can export it.
• Beware of tied contracts. Some monitoring services come bundled with a long energy contract. Read the Principal Terms and see contract terms to check.
• Look for ongoing fees. Cloud subscriptions can undo the saving.

Make it a habit

Pick an owner, a day each week and a place to record the result. Review each month: is use higher or lower than the same month last year? Is the overnight baseload falling? Share the results with staff; people switch things off when they see the cost. For a bigger programme of savings, see saving energy in a small business and business energy audit.

Next steps

1. Take a meter reading today and again in a week.
2. Do the Friday-to-Monday test above.
3. Ask your supplier whether you can access smart or half-hourly data online.
4. Buy a plug-in meter for the three biggest suspects.