Guide · Costs

Plug-in solar cost and savings: how the numbers actually work

A complete plug-in solar kit in the SocketPower range costs between £599 and £1,199 including VAT, with G98 notification handling included. What it saves depends on generation at your address and on how much of that generation you use at the time it happens — so payback is a range, not a promise, and this guide shows you how the estimate is built rather than asking you to trust a single number.

Last reviewed: 13 August 2026

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Kit prices
£599 – £1,199 inc. VAT
Included
G98 notification handling
Payback
An estimate, not a promise
Export income
Not assumed

What you actually pay

The purchase is a complete matched kit at a single price. There is no installation charge in the SocketPower model because the kit connects to an existing suitable socket rather than to your fixed wiring — but that is a description of the product, not a VAT position, and none of these prices should be read as a zero-rated installation.

Current SocketPower RRPs (inc. VAT where applicable)
KitDC capacityAC outputRRP
SocketPower Pro Compact 515W515W (1 × 515W)799 VA£599
SocketPower Pro Duo 890W890W (2 × 445W)799 VA£999
SocketPower Pro Plus 1030W1030W (2 × 515W)799 VA£1,099
SocketPower Pro Max 1260W1260W (2 × 630W)799 VA£1,199

Costs people forget

Budget for anything your property needs before the kit can be used safely: a suitable outdoor socket installed and certified by a qualified electrician if you do not already have one, an upgrade to residual-current protection if your circuit lacks it, and any ballast, frame or fixing your chosen position needs beyond the hardware supplied. Those costs sit with your property, not with the kit, and they vary enormously.

How we estimate savings

Our savings calculator works in four steps, and it is deliberately conservative at each one:

The estimate, step by step
StepWhat happensWhy it varies
1. GenerationDC panel capacity is converted to an annual kWh figure using a yield assumption for the location and aspect.Latitude, orientation, tilt, shading and weather all move this substantially.
2. ClippingGeneration above the inverter's AC ceiling is discarded, because the device cannot output more than its limit.The larger the DC array relative to the AC limit, the more midday output is clipped.
3. Self-consumptionOnly the share used at the moment it is generated is counted as a saving.Daytime occupancy, appliance timing and household size change this dramatically.
4. ValueSelf-consumed kWh are multiplied by your electricity unit rate.Tariffs change, and future rates are unknowable.

The variables that move the answer most

Ranked by impact, roughly

  • Self-consumption share — the single biggest lever. A household that is out all day saves far less from the same generation.
  • Shading — partial shade on a panel costs disproportionately more than its share of the surface area.
  • Orientation and tilt — south maximises the peak; east and west spread output across the day, which can suit usage better.
  • Electricity unit rate — the same kWh is worth more on an expensive tariff, and rates change over time.
  • Location — annual irradiance differs meaningfully between the south of England and northern Scotland.
  • DC capacity above the AC limit — helps in weak light, does nothing at a bright midday peak.

Because of that ordering, two identical kits at two addresses can differ by a factor of two or more in annual saving. Anyone quoting you a single confident number for “what you will save” without asking about your occupancy is guessing.

Reading a payback figure sensibly

Divide the kit price by the estimated annual saving and you get a payback in years. Treat it as a scenario, not a forecast. Run the calculator at a pessimistic self-consumption share as well as an optimistic one, and be comfortable with the pessimistic case before you buy. A 10-year warranty on panel and inverter, subject to SocketPower terms, gives you a sense of the expected service life the estimate is spread across.

Cost questions

Sources

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Editorial note · Last reviewed 13 August 2026

Written and reviewed by SocketPower, a trading name of Storm Renewables Ltd (SC802881). This guide is general information about plug-in solar in Great Britain, not electrical design advice for your property. Always follow the instructions supplied with your product and use a qualified electrician for any work on your fixed wiring.

Plug-in solar in Great Britain: the framework covers single-phase solar PV with a maximum inverter apparent output of 800 VA, and SocketPower devices are limited to 799 VA continuous AC output. Plug-in batteries and battery-integrated devices are outside the framework and are not sold by SocketPower. The current G98 arrangements allow one plug-in solar device per household, and network notification remains required — SocketPower handles the applicable notification for kits bought from us. This framework applies in Great Britain from 27 August 2026 and not in Northern Ireland. Always follow the instructions supplied with your product, check that your socket and circuit are suitable, never use extension leads, multiway adaptors, travel adaptors or plug-in RCD adaptors, and obtain any permissions you need before installing.