What is a time-of-use electricity tariff?
A time-of-use tariff charges different electricity unit prices at different times. Half-hourly consumption records show when your business uses energy, helping you assess off-peak opportunities [S1]. A 30-minute meter record does not itself establish a changing price. Check your contracted time bands and all charges before scheduling vehicles or batteries around them [S1], [S2]. Checked October 2026.
What does a time-of-use tariff mean for your site?
A time-of-use tariff is an electricity contract with unit prices that vary according to when you consume energy. Your agreement may use day, night and peak bands. Half-hourly records measure consumption in 30-minute periods; measurement and the price structure are separate matters [S1].
Why it matters for your site: a depot that can charge parked vehicles overnight has a different opportunity from a visitor car park whose customers need immediate daytime charging. Smart charging should account for departure requirements as well as the electricity price [S2].
How do peak rates and half-hourly pricing differ?
A tariff can have fixed time bands rather than a new price in every settlement period. Ofgem distinguishes half-hourly consumption data from the option to choose a time-of-use tariff [S1]. Ask for the unit-rate schedule, clock-change treatment and any seasonal bands in writing.
For an illustration, assume charging uses 100 kilowatt-hours (kWh), the unit of energy, at either 30p or 15p per kWh. The energy components are 100 × £0.30 = £30 and 100 × £0.15 = £15. These are assumed prices, not market rates or a whole-bill saving.
How should charging and batteries use the tariff?
Check when vehicles are present, the energy needed before departure and the site’s power limit. Scheduling charging can shift demand; it cannot create extra connection capacity [S2].
Read smart charging for operating controls. Use battery tariff arbitrage for the separate calculation including storage losses and operating costs.
Compare the complete bill with business electricity data. The charging cost tool helps translate energy prices into charging costs.
Next step
Bring your contract and consumption profile to the site check, then get matched with an installer that covers your area.
Piggy Pineapple Ltd operates this referral service. We refer enquiries to installer partners and may be paid a fee. Our owner holds shares in at least one partner. Before sharing your details, we name the proposed partner and disclose any shareholding our owner holds in it.
Common questions
Does half-hourly metering mean your price changes every half-hour?
No. Half-hourly settlement uses consumption records. A time-of-use price depends on the supply contract; the meter data alone does not set your tariff [S1].
Are all night hours off-peak?
Use the time bands in your contract. Ofgem describes time-of-use tariffs as an opportunity to use electricity off peak, rather than setting universal business tariff hours [S1].
Can vehicles charge during lower-priced periods?
Smart controls can schedule charging, provided the vehicles are connected and can receive enough energy before departure. Include operational requirements in the schedule [S2].
Does the same price apply to imports and exports?
Do not assume so. The smart charging action plan distinguishes purchasing electricity from providing flexibility or exporting vehicle energy; obtain the applicable terms separately [S2].
What data helps assess a time-of-use tariff?
Obtain your half-hourly consumption profile and apply the proposed prices to the relevant periods. Ofgem identifies using consumption information to assess off-peak opportunities [S1].
Ask about your site
Sources
- Moving to half-hourly energy reads - a guide for businesses, Ofgem,Last checked 19 October 2026
- Electric vehicle smart charging action plan, Department for Energy Security and Net Zero,Last checked 19 October 2026