Solar Energy Concepts

Fundamentals

Flat vs Pitched vs Vertical: How Roof Type Affects Your 10-Year Solar ROI

  • 28 degree pitched roof vs 6 degree flat: only 16% difference per kWp in real-world UK data over 3 years
  • Winter is where angle earns its keep — pitched roof advantage peaks at +78% in January, drops to just +8% by June
  • July is the one month flat wins — gazebo edges the pitched roof by 1.9% when the sun is highest
  • More panels at a bad angle beats fewer at the perfect angle — the flat gazebo nearly doubled total system output
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An image of a wall with solar panels from the ground up. On a nice sunny day.
Fundamentals

Mounting Solar Panels on a Wall: Complete UK Guide (2026)

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My Components

Best Solar Panel Optimisers UK: Tigo vs SolarEdge (2026 Comparison)

  • Solar panel optimisers let each panel produce power independently, so shade on one panel does not drag down the rest of the string.
  • Two brands dominate the UK market: Tigo and SolarEdge.
  • For most UK homes, Tigo optimisers are the better choice: they work with any inverter, cost less per unit, and Tigo’s global dataset of 105,000 sites shows an average 8.7% energy gain.
  • SolarEdge optimisers only work with SolarEdge inverters but include built-in SafeDC shutdown and tighter portal integration.
  • NREL data: optimisers recover 3-4.5% in light shade, 15-18% in moderate shade, and 18-22% in heavy shade.
  • Cost premium: roughly £30-50 per panel extra.

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An image of a server rack type battery comprising of 3 battery units in a server rack. The door is pen and we can see the batteries inside.
My Components

Fogstar 15kWh Battery: 3-Year Owner’s Review

  • Real Home Battery Reliability Data: 600 cycles over 3 years with only ~10% capacity loss — well within the manufacturer-rated 6,000-cycle lifespan at 80% retained capacity.
  • Battery Expectations vs Reality: I changed my usage dramatically in late 2024 (nightly grid charging to 100%), and the batteries have handled the intensive daily cycling without issue.
  • Cost-Effective Storage: At £2999.99 for 15kWh, the Fogstar Rack still offers strong price-to-capacity value, though newer DIY kits are closing the gap.
  • UK-Specific Design: Self-heating cells for sub-zero charging, local customer support, and an active owner community make this battery well-suited to UK conditions.
  • Honest Drawbacks: Winter balancing quirks required a BMS firmware update — a manageable tradeoff I document in full below.
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