Your smart meter is doing far more than sending readings to your supplier. For UK SMEs running shops, offices, restaurants, warehouses, or workshops, the underlying business smart meter data is one of the most practical tools available to identify waste, challenge high bills, and prepare for a renewal negotiation with real evidence behind you.
Reading Your Half-Hourly Consumption Data
For electricity, half-hourly data can help you see when power is being used. Gas data may be supplied at a different interval. Ask your supplier how to obtain the available history, its units and whether any readings are missing or estimated. The government's non-domestic smart-meter data guidance explains the data offer.
Look at a full week rather than a single day. You want to see the natural shape of your consumption — when it rises, when it drops, and whether it ever truly reaches zero during overnight hours. A flat baseline running through the night suggests equipment is drawing power continuously.
Pay particular attention to Monday mornings. If consumption jumps sharply the moment trading begins, that is normal. If it is already elevated before anyone arrives, check whether that use is necessary. Refrigeration, security, servers, ventilation and appropriate preheating can all have legitimate loads.
Spotting Out-of-Hours Usage
Out-of-hours consumption is one of the most common — and correctable — sources of waste in small business premises.
Export your half-hourly data and identify your core closed hours. For a retailer, that might be midnight to 7 am. For a restaurant, it might be 2 am to 9 am. Filter those rows and calculate the total.
- Heating and cooling systems are frequent culprits. A programmer set to the wrong schedule or a thermostat that never switches to setback mode can run equipment through the night at near-full load
- Lighting circuits left on in storage areas, stairwells, or back-of-house spaces are easy to overlook but consistent drains
- Refrigeration units will always show some overnight draw, but a sudden increase compared with previous weeks can signal a failing door seal, a blocked condenser, or a unit working harder than it should
- IT and catering equipment such as ovens on standby, commercial dishwashers, and servers without power management settings all contribute
Once you have identified the hours and approximate load, you can begin physically checking equipment in those categories.
Step-by-Step: Turning Data Into Action
- Step 1 — Download three to four weeks of half-hourly data from your supplier portal or smart meter app. If it is not visible, ask your supplier how to request the available data
- Step 2 — Identify your trading hours and mark out-of-hours periods clearly in a spreadsheet
- Step 3 — Calculate your overnight baseline — the consistent minimum load running during closed hours
- Step 4 — Compare weeks — look for any week where the baseline is noticeably higher, which may indicate a fault or a recently changed setting
- Step 5 — Walk the premises during or after a closed period and match what you find — lights, displays, equipment — against the load you identified
- Step 6 — Log any changes you make so you can measure the impact in subsequent weeks of data
Using Data Before Your Tariff Renewal
Check your contract's actual end date, notice requirements and expiry terms. Out-of-contract prices or automatic renewal may apply if no replacement is arranged; that is not the same as the deemed arrangement commonly encountered by a new occupier. Use our renewal timetable.
Before you request an energy comparison, gather representative consumption history, ideally including seasonal changes where available. Tell the person quoting about planned operating changes. A different consumption profile may affect a quotation, but lower use does not guarantee a lower unit rate.
If your data shows you have already reduced out-of-hours waste, bring that evidence to the renewal conversation. This helps make the forecast realistic; the price still depends on the supplier, market conditions and your site.
For a full overview of business electricity and gas products available to UK SMEs, the Aarubi business electricity and gas section covers the main contract types and what to look for when switching.
Action Checklist
- Download three to four weeks of half-hourly consumption data from your supplier portal
- Identify and total your out-of-hours usage across a typical week
- Check heating programmers, lighting circuits, and refrigeration units for incorrect settings or faults
- Note any weeks with an unusually high overnight baseline and investigate the cause
- Log the date and nature of any changes so you can measure improvement
- Pull updated data at least six weeks before your contract renewal date
- Use your consumption profile as supporting evidence when you compare suppliers
Related business energy FAQs
For concise answers on this topic and links to official guidance, see our business energy FAQs.
Reviewed on 30 September 2026.
