Solar explained to clever people by people who are not trying to be clever

Solar Panels in TW11 (Richmond upon Thames)

See if solar pays off for you in Richmond upon Thames — price, savings and payback in under a minute (official UK data).

Solar Calculator

Change the settings below to see how costs and savings work for your situation.

System Size

Roof Direction

Battery Storage

Export Value

Your Numbers

Break-even
12.2 years
After this, it's pure profit
Upfront Cost
£6,104
What you pay to get started
Annual Benefit
£502
What you save every year
Profit Over 25 Years
£6,441
After paying itself off, you're this much ahead

Ready to Get Started?

Get your free quote from Blue Ape Renewables. They'll connect you with MCS-certified installers in your area and handle all the paperwork.

Get Solar Quote →
4.8★ Trustpilot • Octopus Energy trusted partner • MCS certified • No obligation
How we calculate this

Solar generation: Based on typical south-facing roof at 35° angle. We account for weather, dirt, and system losses (14%).

How much you'll use directly:

  • Without battery: You'll use about 40% of what you generate. The rest gets sold back to the grid.
  • With 5 kWh battery: You'll use about 70% (battery stores extra for evening use).
  • With 10 kWh battery: You'll use about 75% (more storage means less exported).
  • Panel-only payback: Bigger systems don’t shorten payback—cost and savings rise together per kW.
  • Battery & payback: Batteries raise self-use and cut bills, but added hardware cost often lengthens break-even at typical UK rates.
  • When a battery can still make sense:
    • Evening-heavy usage patterns
    • Time-of-use tariffs / cheap night rates
    • Low export rate vs. high unit rate
    • Heat pump or EV charging synergy
    • Optional backup/resilience (system-dependent)
    • Lower evening-hour CO₂ vs. grid

Costs: Battery prices are typically £700 per kWh. Export tariffs vary by supplier (usually 5–15p per kWh).

Grid connection: Systems up to about 3.7 kW typically need just a notification (G98). Larger systems may need permission (G99).

These are typical values based on average usage patterns. Your actual results will vary based on your roof, shading, and how you use electricity.

Your area in context

Read the full story

A typical roof here lands around 3.0 kW, with most eligible homes comfortably fitting within 3–6 kW. Each kilowatt of panels produces roughly 998 kWh per year on a south-facing roof. We value self-used electricity at 26.9p and exported surplus at a baseline 10p via SEG. Use the calculator above for your exact tariff.

Unit rate
26.9p/kWh
Standing charge
47.6p/day
Sunshine yield (south)
998 kWh/kW
Export price (baseline)
10p/kWh

Browse the scenarios below. Each battery size has its own expand — open the one that matches your plan (or just explore). For each system size (2–8 kW) we show annual output, how much you use directly, what gets exported, annual benefit, upfront cost, break-even, and a 20-year net. Negative numbers are possible — that’s the honest trade-off when adding more battery than your usage profile justifies.

No battery 5 kW example → Annual benefit: £836, Upfront: £10,173, Break-even: 12.2 yrs
System Annual output Self-use Exported Bill saving Export income Annual benefit Upfront cost Break-even 20-year net
2 kW 1995 kWh 798 kWh 1197 kWh £215 £120 £335 £4,069 12.2 yrs £2,621
3 kW 2992 kWh 1197 kWh 1796 kWh £322 £180 £502 £6,104 12.2 yrs £3,932
4 kW 3990 kWh 1596 kWh 2394 kWh £430 £239 £669 £8,138 12.2 yrs £5,243
5 kW 4988 kWh 1995 kWh 2992 kWh £537 £299 £836 £10,173 12.2 yrs £6,554
6 kW 5985 kWh 2394 kWh 3591 kWh £644 £359 £1,004 £12,207 12.2 yrs £7,864
7 kW 6982 kWh 2793 kWh 4190 kWh £752 £419 £1,171 £14,242 12.2 yrs £9,175
8 kW 7980 kWh 3192 kWh 4788 kWh £859 £479 £1,338 £16,276 12.2 yrs £10,486

Assumptions: south-facing, sensible tilt; self-use shares from site rules; export at 10p baseline. Costs: panels £/kW = 2,035, battery £/kWh = 700.

3 kWh battery 5 kW example → Annual benefit: £1,005, Upfront: £12,273, Break-even: 12.2 yrs
System Annual output Self-use Exported Bill saving Export income Annual benefit Upfront cost Break-even 20-year net
2 kW 1995 kWh 1197 kWh 798 kWh £322 £80 £402 £6,169 15.3 yrs £1,872
3 kW 2992 kWh 1796 kWh 1197 kWh £483 £120 £603 £8,204 13.6 yrs £3,857
4 kW 3990 kWh 2394 kWh 1596 kWh £644 £160 £804 £10,238 12.7 yrs £5,843
5 kW 4988 kWh 2992 kWh 1995 kWh £806 £200 £1,005 £12,273 12.2 yrs £7,829
6 kW 5985 kWh 3591 kWh 2394 kWh £967 £239 £1,206 £14,307 11.9 yrs £9,815
7 kW 6982 kWh 4190 kWh 2793 kWh £1,128 £279 £1,407 £16,342 11.6 yrs £11,801
8 kW 7980 kWh 4788 kWh 3192 kWh £1,289 £319 £1,608 £18,376 11.4 yrs £13,787

Assumptions: south-facing, sensible tilt; self-use shares from site rules; export at 10p baseline. Costs: panels £/kW = 2,035, battery £/kWh = 700.

5 kWh battery 5 kW example → Annual benefit: £1,089, Upfront: £13,673, Break-even: 12.5 yrs
System Annual output Self-use Exported Bill saving Export income Annual benefit Upfront cost Break-even 20-year net
2 kW 1995 kWh 1396 kWh 598 kWh £376 £60 £436 £7,569 17.4 yrs £1,147
3 kW 2992 kWh 2095 kWh 898 kWh £564 £90 £654 £9,604 14.7 yrs £3,470
4 kW 3990 kWh 2793 kWh 1197 kWh £752 £120 £872 £11,638 13.4 yrs £5,793
5 kW 4988 kWh 3491 kWh 1496 kWh £940 £150 £1,089 £13,673 12.5 yrs £8,117
6 kW 5985 kWh 4190 kWh 1796 kWh £1,128 £180 £1,307 £15,707 12.0 yrs £10,440
7 kW 6982 kWh 4888 kWh 2095 kWh £1,316 £209 £1,525 £17,742 11.6 yrs £12,764
8 kW 7980 kWh 5586 kWh 2394 kWh £1,504 £239 £1,743 £19,776 11.3 yrs £15,087

Assumptions: south-facing, sensible tilt; self-use shares from site rules; export at 10p baseline. Costs: panels £/kW = 2,035, battery £/kWh = 700.

7.5 kWh battery 5 kW example → Annual benefit: £1,115, Upfront: £15,423, Break-even: 13.8 yrs
System Annual output Self-use Exported Bill saving Export income Annual benefit Upfront cost Break-even 20-year net
2 kW 1995 kWh 1456 kWh 539 kWh £392 £54 £446 £9,319 20.9 yrs £-401
3 kW 2992 kWh 2185 kWh 808 kWh £588 £81 £669 £11,354 17.0 yrs £2,024
4 kW 3990 kWh 2913 kWh 1077 kWh £784 £108 £892 £13,388 15.0 yrs £4,449
5 kW 4988 kWh 3641 kWh 1347 kWh £980 £135 £1,115 £15,423 13.8 yrs £6,873
6 kW 5985 kWh 4369 kWh 1616 kWh £1,176 £162 £1,338 £17,457 13.0 yrs £9,298
7 kW 6982 kWh 5097 kWh 1885 kWh £1,372 £189 £1,561 £19,492 12.5 yrs £11,722
8 kW 7980 kWh 5825 kWh 2155 kWh £1,568 £215 £1,784 £21,526 12.1 yrs £14,147

Assumptions: south-facing, sensible tilt; self-use shares from site rules; export at 10p baseline. Costs: panels £/kW = 2,035, battery £/kWh = 700.

10 kWh battery 5 kW example → Annual benefit: £1,132, Upfront: £17,173, Break-even: 15.2 yrs
System Annual output Self-use Exported Bill saving Export income Annual benefit Upfront cost Break-even 20-year net
2 kW 1995 kWh 1496 kWh 499 kWh £403 £50 £453 £11,069 24.5 yrs £-2,016
3 kW 2992 kWh 2244 kWh 748 kWh £604 £75 £679 £13,104 19.3 yrs £476
4 kW 3990 kWh 2992 kWh 998 kWh £806 £100 £905 £15,138 16.7 yrs £2,969
5 kW 4988 kWh 3741 kWh 1247 kWh £1,007 £125 £1,132 £17,173 15.2 yrs £5,461
6 kW 5985 kWh 4489 kWh 1496 kWh £1,208 £150 £1,358 £19,207 14.1 yrs £7,953
7 kW 6982 kWh 5237 kWh 1746 kWh £1,410 £175 £1,584 £21,242 13.4 yrs £10,445
8 kW 7980 kWh 5985 kWh 1995 kWh £1,611 £200 £1,811 £23,276 12.9 yrs £12,937

Assumptions: south-facing, sensible tilt; self-use shares from site rules; export at 10p baseline. Costs: panels £/kW = 2,035, battery £/kWh = 700.

13.5 kWh battery 5 kW example → Annual benefit: £1,149, Upfront: £19,623, Break-even: 17.1 yrs
System Annual output Self-use Exported Bill saving Export income Annual benefit Upfront cost Break-even 20-year net
2 kW 1995 kWh 1536 kWh 459 kWh £414 £46 £459 £13,519 29.4 yrs £-4,331
3 kW 2992 kWh 2304 kWh 688 kWh £620 £69 £689 £15,554 22.6 yrs £-1,771
4 kW 3990 kWh 3072 kWh 918 kWh £827 £92 £919 £17,588 19.1 yrs £789
5 kW 4988 kWh 3840 kWh 1147 kWh £1,034 £115 £1,149 £19,623 17.1 yrs £3,348
6 kW 5985 kWh 4608 kWh 1377 kWh £1,241 £138 £1,378 £21,657 15.7 yrs £5,908
7 kW 6982 kWh 5377 kWh 1606 kWh £1,447 £161 £1,608 £23,692 14.7 yrs £8,468
8 kW 7980 kWh 6145 kWh 1835 kWh £1,654 £184 £1,838 £25,726 14.0 yrs £11,027

Assumptions: south-facing, sensible tilt; self-use shares from site rules; export at 10p baseline. Costs: panels £/kW = 2,035, battery £/kWh = 700.

Figures are illustrative and use the same method as the calculator above. For exact results, adjust your roof direction, tariff, and usage in the calculator.

Your Area at a Glance

Your Electricity Rate
26.92p/kWh
Daily Fixed Charge
47.60p/day
Local Sunshine
998kWh/kW
A 1 kW system generates ~998 kWh per year. A typical home uses ~2,700 kWh per year.
Typical System Size
3.0kW
For houses & bungalows in this area

⚠️ This area is predominantly flats. Many residents require freeholder approval for solar installations. System size shown reflects houses and bungalows only.

Local Property Data

Property Types

Houses: 42% • Flats: 51% • Bungalows: 1% Based on 6,347 properties

Coverage

Richmond upon Thames (100%)

Areas Covered

Teddington, Hampton Wick & South Teddington, Fulwell & Hampton Hill, South Twickenham, Ham, Petersham & Richmond Riverside

Data Sources & Assumptions

Solar yield: PVGIS (EU Joint Research Centre), January 2025 data

Electricity rates: Ofgem price cap, Q4 2025

Installation costs: MCS certified installer data, March 2025

Property data: EPC open data (Open Government Licence), aggregated

All estimates are typical values. Actual results vary based on your specific situation, roof characteristics, and usage patterns.