22 panels · 15 kWh battery · Hampshire, UK
One roof.
Every number published.
This is our own solar and battery setup on a fairly ordinary UK house, and really it's just a place to track one thing: how quickly it pays back, and whether real life keeps pace with the proposal's estimate. So every day's numbers go up here automatically, straight off the inverter, cloudy days and all. It's all run with Home Assistant and Predbat, and the config files that make it work are public too, in case they save someone else the faff.
Yesterday · Sunday, 2 August 2026
Payback progress · £11,999 system
A running total of savings against what the same usage would have cost with no solar or battery, tracked every day since commissioning. Full charts →
VPP earnings · grid-balancing events
£4.27from 1 grid event at £1/kWh · £10/month minimum guaranteed
£25 referral Got a battery? We both get £25.
What's here
The system
22 Aiko 475W panels on an east/west roof, a Sigenergy hybrid inverter and 15.06 kWh of battery. £11,999 fully installed. Specs & warranties →
The brain
Home Assistant on a £50 second-hand Dell, with Predbat planning every half hour against Octopus Agile prices and a Solcast forecast. How it works →
The configs
The apps.yaml, automations and helpers that run this Sigenergy and Predbat setup. Sanitised, annotated and free to copy. Help yourself →
Why bother with all this? Honestly, it's mostly for us. A £12k punt deserves an honest scoreboard, so rather than take the proposal's payback estimate on trust we wanted to track how quickly it really pays back, day by day, against that projection. The Predbat-and-Sigenergy setup took enough trial and error that we've put the configs up too, in case they save someone else some of it. Start with the install diary.