Domestic Solar — Designed Around Your Home, Not a Package

Solar + battery + tariff as one decision

The single biggest mistake on UK domestic solar is treating panels, battery and tariff as separate decisions. KMM models them together. The right system on the wrong tariff under-performs; the right tariff with a too-small battery wastes export potential; the right battery with a too-small PV array creates an evening shortfall. We run the maths across the combinations.

Example trade-offs we discuss with most domestic clients:

• Octopus Intelligent / Cosy / Go with a battery sized to cover overnight cheap-rate import → arbitrage against daytime peak. Suits homes with EVs and / or heat pumps.
• Octopus Agile with battery + smart export → real-time arbitrage against the half-hourly wholesale market. Higher engagement, higher upside.
• Standard SEG export with a smaller battery → optimised for self-consumption, simpler operation. Suits households with a steady daytime presence.

Economy 7 — what it actually means

Economy 7 is a legacy two-rate tariff with cheap overnight electricity (typically 7 hours, often 00:30–07:30) and higher-rate daytime. Older homes with storage heaters or immersion heaters still use it. With a modern battery, Economy 7 can be optimised — charge the battery overnight on cheap rate, discharge during daytime peak, supplement with solar. KMM models this where relevant rather than assuming Economy 7 is always worth switching off.

Smart Export Guarantee — what we actually advise

SEG is the mandated export tariff scheme replacing the old Feed-in Tariff. Every UK supplier with over 150,000 customers must offer an SEG rate, but rates vary materially. We don't lock you in to a specific supplier — we model your projected export across the SEG landscape, recommend the strongest options for your profile, and you can switch SEG provider separately from your import supplier.

Advanced battery configurations

Modern domestic battery systems can do more than store solar — they support grid arbitrage, time-of-use shifting, virtual power plant participation, EV charging integration and (with the right hardware) whole-home backup. KMM scopes these capabilities against your goals rather than fitting the cheapest unit. Battery sizing decisions on most homes deserve more attention than they typically get from installers.

Domestic and farm crossover

Many KMM domestic clients are also farm owners or operators. The two design conversations often merge — household solar on the farmhouse roof, ground-mount or larger PV array on the agricultural buildings, battery sized for combined loads, and a procurement strategy spanning both. KMM handles this as one project where relevant.