Energy Stack

Energy Stack / Battery

Battery

Home storage, when it earns its keep and when it doesn't.

A battery is the most expensive single decision in the stack. Capacity matters less than the shape of your day and the tariff you are on. The case is sometimes obvious, often marginal, and worth doing the numbers on properly.

Guides

11 reference pages on storage.

Sizing

How much battery do you actually need?

Comes down to your evening load shape rather than a marketing-friendly round number.

Chemistry

LFP vs NMC, the short version

For almost every UK domestic install, the answer is LFP. Here is the long-form reason.

Hybrid

All-in-one hybrid inverters

Tidiness against a single point of failure. The trade-off is worth thinking about before quoting time.

Payback

Working through a real payback

Including the bits brochures tend to leave out: degradation, round-trip losses, opportunity cost.

VPP

Virtual power plants in 2026

Octopus Tesla Energy Plan and the others. Which schemes actually move the needle.

V2H

Vehicle-to-home, status check

What is shipping, what is promised, what is still a slide.

Calculator

Battery sizing.

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Battery sizing

Drop in your evening load shape and we work out the smallest battery that catches most of your spare solar without leaving a lot of unused capacity sitting in the cupboard.

Featured article.

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2026-05-08 · Battery · 14 min

A year with a 5 kWh battery on a small solar array

A look at the meter data after twelve months. The payback came in a couple of years earlier than the spreadsheet expected, mostly because of the tariff rather than the panels.

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