What to ask if a quote relies on a special energy tariff
Heat-pump rates, time-of-use and multi-rate tariffs can make savings look better. Questions to ask before you sign.
If the saving depends on a special tariff, say so
Electricity unit rate drives heat pump running cost. Some quotes use a heat-pump or time-of-use tariff that lowers the average p/kWh in the spreadsheet. That can be fair. It can also disappear if you switch supplier, move home, or the product is withdrawn.
Six things to get in writing
- Exact tariff name and supplier
- Eligibility (meter type, payment method, region)
- Standing charge and any daily fees
- Off-peak hours vs when your heating and hot water actually run
- Exit fees and how long the rate is fixed
- Annual running cost on a standard tariff you could use instead
Hot water timing
If immersion or heat pump hot water runs outside cheap windows, the average cost per kWh rises. Ask how the model schedules hot water.
Solar and battery stacks
Some quotes combine export/import products with heat pumps. Treat stacked savings as a scenario to verify, not a single headline number.
Run your figures through the Heat Pump Quote Reality Checker with “special tariff” ticked and again with a standard rate.
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