Smart Meter & Time-of-Use Tariff Savings Calculator
Calculate potential savings from smart meter time-of-use tariffs like Octopus Agile, Intelligent Octopus, and Economy 7.
Smart Tariff Guide
How Time-of-Use Tariffs Work
Smart meters enable electricity suppliers to offer time-varying rates — charging less when grid demand is low (overnight) and more during peak hours. This benefits both consumers (savings) and the grid (demand shifting). Economy 7: the original time-of-use tariff. 7 hours cheap rate overnight (typically midnight-7am or 1am-8am). Standard day rate for remaining 17 hours. Best for: storage heaters, hot water immersion heaters, overnight EV charging. Intelligent Octopus: links to your EV charger or
Octopus Agile
Octopus Agile: half-hourly rates based on wholesale electricity prices. Rates can go negative during windy/sunny periods — you get paid to use electricity. Rates can be very high during peak demand. Requires: smart meter with half-hourly data enabled. App to check rates in advance. Ability to schedule appliances, EV, heating. Best for: tech-savvy users, EV owners, homes with battery storage. Average savings: 10-25% vs standard tariff for engaged users. Requires active participation — passively f
EV Charging and Smart Tariffs
An EV fundamentally changes the economics of smart tariffs. Typical EV consumption: 3,000-6,000 kWh/year for average mileage. At 24p/kWh standard tariff: £720-1440/year. At 7.5p/kWh Intelligent Octopus overnight: £225-450/year. Annual saving: £495-990/year just on EV charging. With an annual electricity tariff standing charge saving of £100-200: a smart tariff can save EV owners £600-1,200/year vs standard. Heat pumps: similar logic. Heat pumps typically use 3,000-8,000 kWh/year for space heatin
Battery Storage and Solar
Battery storage unlocks further smart tariff savings: charge battery cheaply overnight. Use stored cheap electricity during expensive peak hours. Solar and battery: sell solar to grid during peak (high export rate). Charge battery from grid overnight at cheap rate when solar insufficient. Octopus Flux tariff: designed for solar + battery households. Import rate overnight ~8p/kWh. Export rate midday ~15p/kWh. Payback on battery (Powerwall ~£9,000): approximately 10-15 years at current rates witho
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