Estimate savings

Solar savings calculator: how much of the annual benefit is bill reduction, and how much is export income? Start with measured kWh or a clearly explained bill estimate.

Compare payback and storage

Solar payback calculator: how does the installed cash cost compare with annual benefit, and what additional return does a battery offer?

Existing-owner battery comparison: assess additional storage without charging the original solar purchase again.

Check an existing proposal

Solar quote checker: enter one or two proposals to identify missing scope, inconsistent arithmetic and specific questions to ask. It does not invent an installer-quality score.

Understand the assumptions

Methodology and source register: equations, units, dated assumptions and limitations used by the tools. Results can be printed with their inputs and version.

Next useful guides

Solar Payback Calculator for UK Homes Estimate solar payback, separate bill savings from export income and compare the additional return from a battery with transparent inputs. Solar Savings Calculator for UK Homes Estimate annual solar bill reduction and export receipts using actual kWh or an explicit electricity-bill estimate, then carry inputs to detailed payback. Solar Quote Checker Enter one or two solar or battery proposals to check scope and arithmetic. You get missing-information questions and an explained comparison, with no... Add a Battery to Existing Solar Adding storage can be assessed after solar has been installed, but the existing inverter, metering and export agreement need checking. Start with measured...