Smart Tariff Savings London 2026 — Real Numbers (Not Hype)

London standard variable tariff mid-2026: around 27p/kWh import, 28p/day standing charge. A 3,500 kWh/year household pays roughly £1,050 + £102 standing = £1,152/year.

Adding an EV (3,000 kWh/year for 10,000 miles): £810. Total £1,962.

Adding a heat pump (4,000 kWh/year for ASHP replacing gas): £1,080. Total £3,042.

Adding solar + battery without smart tariff: saves £400-700/year on import. Total £2,342-2,642.

These are the numbers smart tariffs are competing with.

Off-peak rate around 7p/kWh for the EV charging slot. Charging 3,000 kWh/year at 7p = £210 vs £810 on standard. Saving £600/year.

Cheap-rate window covers all home electricity in that window. Dishwasher and washing machine on timer save another £40-60/year.

Realistic total saving: £640-680/year on a typical EV-using household.

Catch: peak rate (5-8pm) is 27-30p, sometimes slightly higher than standard. If you can't avoid peak usage (work-from-home stay-at-home parents), savings are 15-20% lower.

Heat pump usage 4,000 kWh/year, of which around 60% can be shifted to cheap windows with a smart thermostat schedule.

Cheap rate around 13p/kWh, peak around 32p, standard around 25p. Versus a flat 27p tariff: shift 2,400 kWh from 27p to 13p saves £336.

Add hot water and dishwasher on cheap-window timers: another £80-120/year.

Realistic total saving: £400-500/year for an ASHP household. Less than Intelligent Go for EV, but the heat pump itself is the bigger win — moving off gas in 2026 saves £600-900/year on heating alone.

A 6 kW solar + 13.5 kWh battery system in London generates around 5,400 kWh/year. Self-consumption typically 60-70% with battery; export 30-40%.

Agile import averaging 14-18p in the day (when solar is generating but household has shifted load away), 5-8p overnight (charge battery if needed), 28-35p in peak.

Outgoing Agile export averaging 14-18p, hitting 25-35p at peak grid pricing.

Active management (Home Assistant or Octopus Mini) shifts battery charging to cheapest 6-hour windows daily. Realistic savings vs flat-rate: £700-1,100/year additional on top of basic solar self-consumption savings.

Without active management, Agile can lose you money — avoid manual Agile usage unless you're a tinkerer.

Solar (6 kW) + battery (13.5 kWh) + EV + ASHP + smart everything in a London 3-bed semi:

Baseline cost without smart kit: £3,500-4,200/year (gas + electric).

With solar + battery + Agile + Outgoing Agile + heat pump + EV all working together: £1,400-2,000/year net.

Annual saving: £1,500-2,200. Capex to get there: £20,000-32,000 (solar £8-12k, battery £6-9k, ASHP £8-12k, EV charger £900). With 0% VAT until 1 May 2027 and BUS £7,500 grant, net capex £14,000-22,000.

Payback: 7-12 years. Plus you've protected against energy-price shocks for the lifetime of the kit (20-25 years).

If you have no EV, no heat pump, no solar — a smart tariff saves £40-80/year. Worth doing but not life-changing.

If you have one of (EV, heat pump, solar) — £400-700/year saving is realistic.

If you have two of three — £700-1,100/year.

Full stack — £1,500+/year.

Beware the £2,000+/year claims that assume aggressive peak avoidance plus full-stack equipment. Real households eat dinner during peak and use the dishwasher when they have time. Build in real-life behaviour and the numbers above are honest.