Illustrative examples for learning. Companies are not named unless legally reviewed.
Quote headline: £900/year saving vs current gas
Claimed saving: Roughly 40% vs last year's gas bill
On a standard electricity tariff the annual saving fell to under £150. The grant reduced upfront cost but loan repayments were excluded from the headline comparison. Homeowner asked for a new-boiler comparison and itemised radiator costs before deciding.
Quote headline: 7-year payback
Claimed saving: Based on 70% self-consumption without bill evidence
Using the homeowner's actual half-hourly data, self-consumption was closer to 45%. Payback stretched beyond 12 years unless export tariff rose. Battery degradation was not in the quote assumptions.
Quote headline: Government grant reduces your electricity costs
Claimed saving: Marketing implied ongoing bill reduction from grant
The grant was a capital subsidy on installation, not a tariff saving. Clarifying net capital cost after grant changed the comparison with staying on grid-only supply.
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