Solar panels, batteries, an EV charger, a heat pump and the smart tariff that ties them together. We write the independent guides and build the tools to help you choose, install and run them well.
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Generation
Panels, inverters, microinverters, mounting and the surprisingly large gap between modelled and measured output.
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Storage
Home batteries, hybrid systems, V2H and the long question of whether storage pays back in your lifetime.
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Mobility
Home chargers, smart tariffs, load balancing and the truth about public network reliability.
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Warmth
Air source, ground source, the radiator question, the grants, the noise and the survey that decides it all.
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Tools
No round numbers, no marketing-friendly outputs. Drop in your real inputs, see the assumptions, watch the maths update.
Latest
Battery · 14 min
A 4 kWp roof in Surrey, a 5 kWh battery and a year of half-hourly meter data. We ran the numbers four different ways.
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EV · 11 min
Three differences that matter, seven that the marketing pages want you to weight. We separated them.
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Heat pumps · 17 min
A semi in West Yorkshire. The 14 kW survey was wrong. Here is how to tell when yours is too.
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