Solar Energy Concepts

DIY Solar for UK Homes. Real guides from a real install.

Step-by-step practical guides, component lessons, and hard-earned fixes from a real UK DIY solar setup.

7.15kWpinstalled 6,072kWhgenerated 2025 £1,668/yrmodelled value

Latest field notes

Fundamentals

Germany has over 1.2 million registered plug-in solar systems, built on an 800 watt output cap, a single online registration form, and a safety standard that took nine years to publish.
The UK has decided to legalise plug-in solar, but the only lawful way to connect solar generation today is still a hardwired installation by a registered electrician notified to your network operator.
Every country where plug-in solar actually took off shares three things: an official product safety standard, a one-step registration process, and (in the stronger examples) a legal right for renters to fit one.
The details vary sharply across Europe, from France’s no-export promise and Belgium’s approved-kit list to Switzerland’s stricter 600 watt cap and Lithuania’s flat cash subsidy for installing one.
The UK spec is published and lands where Germany did: 800 VA limit, up to 2,000 W of panels, BS 1363 plug with 5 A fuse. The consultation closed 30 June 2026, and a government response is expected around 22 July, subject to analysis and approval. No kit can be plugged into a UK socket legally today.
German 2-year payback posts usually include free export: UK DIY plug-in kits should assume £0 export income.

Updated 16 Jul 2026 Read Entry →

Practical and DIY

A home battery belongs in a garage, outside or a fire-separated utility room, not a loft, bedroom or escape route: PAS 63100:2024 and BS 7671 Amendment 4 set the rules.
A loft is expressly excluded: PAS 63100 rules out lofts, roof spaces and voids, and joist loading and summer heat make the case worse.
Outside is the preferred spot: it keeps a fire off the living space, but the enclosure must sit 1 m from windows and doors, 2 m from stored fuel, and cope with winter cold.
Indoors needs fire separation, ventilation and detection: a utility room with about 30 minutes of fire separation works; a sealed cupboard, bedroom or hallway does not.
Make the installer justify the location in writing: the exact spot, its fire separation in minutes, ventilation, Grade D2 detection and the manufacturer temperature limits, before you sign.

Updated 16 Jul 2026 Read Entry →

My Components

Buy decision page: Tigo vs SolarEdge vs microinverters for UK quotes and retrofits.
Pick by ecosystem: retrofit = Tigo, new SolarEdge stack = SolarEdge, complex new roof = microinverter quotes.
On clean unshaded roofs, skip optimisers and spend the money on panels or a battery.
Physics companion: when power optimisers help.

Updated 16 Jul 2026 Read Entry →

Fundamentals

Use the calculator below to compare tilt, direction and 10-year ROI for your roof. It covers every UK region; the optimal angle barely changes across a postcode area.
The textbook optimum is 35-40° facing south, but east-west and even vertical setups beat it for many real households.
Flat roofs win summer, steep walls win winter. Match the angle to when you actually use power.

Updated 16 Jul 2026 Read Entry →

Fundamentals

Overpaneling increases UK annual yield, especially in winter and low-light conditions.
The key metric is DC/AC ratio — oversize within inverter and DNO limits.
Done correctly, it improves ROI without automatically requiring a bigger inverter.

Updated 16 Jul 2026 Read Entry →

System Guides

Most UK homes have a single-phase supply, but some homes already have three phase.
G98 permits up to 3.68kW per phase, so a three-phase supply allows up to 11.04kW in total.
You can use a true three-phase inverter or, with DNO agreement, one single-phase inverter on each phase.
Three-phase solar makes most sense with a large array and substantial loads such as a heat pump and EV.

Updated 16 Jul 2026 Read Entry →

Practical and DIY

Sunsynk timer SOC depends on Grid Charge: with it selected the row can be a charge level; without it, discharge towards that level may be allowed.
Find the binding constraint: source-specific current, timer Power, BMS requests, equipment limits, available energy and time can all restrict battery power.
Priority Load and Priority Battery change where solar goes: a timer SOC is not a universal cap on solar charging.
Diagnose in a fixed order: identify the active row and source permissions before changing current limits or protection values.
Keep protection and compliance settings out of experiments: grid code, CT wiring, battery protocol and firmware need the exact manual or an installer.

Updated 16 Jul 2026 Read Entry →

Practical and DIY

Solar Assistant is local Pi monitoring, not a cloud app replacement for glances: real-time data and optional control on your LAN once the link is healthy.
Pick exactly one official connection method: RS485, RS232 where documented, or a supported logger path. Simultaneous methods can give partial or corrupted reads.
If the battery already owns the combined CAN/RS485 port, plan that before you buy: use a documented 2-in-1 or purpose-built split, not a random Ethernet splitter.
Commission by proving power, SOC and grid match: do not start automation until live values agree with the inverter display or app.
Route failures before rewriting settings: CRC and wiring go to the CRC guide; rules and tariffs go to the automation guide.

Updated 16 Jul 2026 Read Entry →

Practical and DIY

You can add a battery and keep your Feed-in Tariff if the generation meter, and any metered export, still records eligible solar correctly.
AC-coupled after the generation meter is the low-risk route: it leaves your certified PV system and its meter untouched, where a hybrid swap re-wires the generating side and has to be re-proven.
Deemed export stays at 50% of generation: solar PV up to 30kW keeps the 50% deemed rate even with a battery and a smart meter, because it is read off the generation meter.
Grid charging is allowed but must be metered cleanly: if a meter cannot separate exported solar from exported grid electricity, you lose the export payment.
Report the change to your Feed-in Tariff licensee: notifying co-located storage with a wiring diagram and battery details is a scheme requirement, not a courtesy.

Updated 16 Jul 2026 Read Entry →