Solar panel cost in Harlow (CM18)

See realistic solar installation costs, savings and payback for CM18 (Harlow) in under a minute using official UK data. Start with the calculator, then get a no-obligation quote from an MCS-certified installer. You can also ask the SolarByPostcode assistant to sanity-check your roof, bills and plans.

Solar Calculator

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System Size

Roof Direction

Battery Storage

Export Value

Your Numbers

Break-even
10.9 years
After this, it's pure profit
Upfront Cost
£7,307
What you pay to get started
Annual Benefit
£670
What you save every year
Profit Over 25 Years
£9,446
After paying itself off, you're this much ahead

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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: The official cost per kW is lower above 4 kW, so a 5–6 kW system can pay back a little faster than a 3–4 kW system on otherwise identical assumptions.
  • 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

Panel costs: Uses March 2026 TIC mean installation costs: £1,827/kW up to 4 kW and £1,628/kW above 4 kW.

Other costs: Battery prices are modelled at £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 4.0 kW, with most eligible homes comfortably fitting within 3–6 kW. Each kilowatt of panels produces roughly 1012 kWh per year on a south-facing roof. We value self-used electricity at 26.4p and exported surplus at a baseline 10p via SEG. Use the calculator above for your exact tariff.

Unit rate
26.4p/kWh
Standing charge
53.9p/day
Sunshine yield (south)
1012 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: £838, Upfront: £9,134, Break-even: 10.9 yrs
System Annual output Self-use Exported Bill saving Export income Annual benefit Upfront cost Break-even 20-year net
2 kW 2024 kWh 810 kWh 1215 kWh £214 £121 £335 £3,654 10.9 yrs £3,048
3 kW 3036 kWh 1215 kWh 1822 kWh £320 £182 £503 £5,481 10.9 yrs £4,571
4 kW 4049 kWh 1619 kWh 2429 kWh £427 £243 £670 £7,307 10.9 yrs £6,095
5 kW 5061 kWh 2024 kWh 3036 kWh £534 £304 £838 £9,134 10.9 yrs £7,619
6 kW 6073 kWh 2429 kWh 3644 kWh £641 £364 £1,005 £10,961 10.9 yrs £9,143
7 kW 7085 kWh 2834 kWh 4251 kWh £748 £425 £1,173 £12,788 10.9 yrs £10,666
8 kW 8097 kWh 3239 kWh 4858 kWh £854 £486 £1,340 £14,615 10.9 yrs £12,190

Assumptions: south-facing, sensible tilt; self-use shares from site rules; export at 10p baseline. Costs: panels £/kW = 1,827, battery £/kWh = 700.

3 kWh battery 5 kW example → Annual benefit: £1,003, Upfront: £11,234, Break-even: 11.2 yrs
System Annual output Self-use Exported Bill saving Export income Annual benefit Upfront cost Break-even 20-year net
2 kW 2024 kWh 1215 kWh 810 kWh £320 £81 £401 £5,754 14.3 yrs £2,274
3 kW 3036 kWh 1822 kWh 1215 kWh £481 £121 £602 £7,581 12.6 yrs £4,461
4 kW 4049 kWh 2429 kWh 1619 kWh £641 £162 £803 £9,407 11.7 yrs £6,648
5 kW 5061 kWh 3036 kWh 2024 kWh £801 £202 £1,003 £11,234 11.2 yrs £8,835
6 kW 6073 kWh 3644 kWh 2429 kWh £961 £243 £1,204 £13,061 10.8 yrs £11,022
7 kW 7085 kWh 4251 kWh 2834 kWh £1,121 £283 £1,405 £14,888 10.6 yrs £13,209
8 kW 8097 kWh 4858 kWh 3239 kWh £1,282 £324 £1,606 £16,715 10.4 yrs £15,396

Assumptions: south-facing, sensible tilt; self-use shares from site rules; export at 10p baseline. Costs: panels £/kW = 1,827, battery £/kWh = 700.

5 kWh battery 5 kW example → Annual benefit: £1,086, Upfront: £12,634, Break-even: 11.6 yrs
System Annual output Self-use Exported Bill saving Export income Annual benefit Upfront cost Break-even 20-year net
2 kW 2024 kWh 1417 kWh 607 kWh £374 £61 £435 £7,154 16.5 yrs £1,537
3 kW 3036 kWh 2126 kWh 911 kWh £561 £91 £652 £8,981 13.8 yrs £4,056
4 kW 4049 kWh 2834 kWh 1215 kWh £748 £121 £869 £10,807 12.4 yrs £6,574
5 kW 5061 kWh 3543 kWh 1518 kWh £935 £152 £1,086 £12,634 11.6 yrs £9,093
6 kW 6073 kWh 4251 kWh 1822 kWh £1,121 £182 £1,304 £14,461 11.1 yrs £11,611
7 kW 7085 kWh 4960 kWh 2126 kWh £1,308 £213 £1,521 £16,288 10.7 yrs £14,130
8 kW 8097 kWh 5668 kWh 2429 kWh £1,495 £243 £1,738 £18,115 10.4 yrs £16,648

Assumptions: south-facing, sensible tilt; self-use shares from site rules; export at 10p baseline. Costs: panels £/kW = 1,827, battery £/kWh = 700.

7.5 kWh battery 5 kW example → Annual benefit: £1,111, Upfront: £14,384, Break-even: 12.9 yrs
System Annual output Self-use Exported Bill saving Export income Annual benefit Upfront cost Break-even 20-year net
2 kW 2024 kWh 1478 kWh 547 kWh £390 £55 £444 £8,904 20.0 yrs £-14
3 kW 3036 kWh 2217 kWh 820 kWh £585 £82 £667 £10,731 16.1 yrs £2,604
4 kW 4049 kWh 2955 kWh 1093 kWh £780 £109 £889 £12,557 14.1 yrs £5,222
5 kW 5061 kWh 3694 kWh 1366 kWh £975 £137 £1,111 £14,384 12.9 yrs £7,840
6 kW 6073 kWh 4433 kWh 1640 kWh £1,169 £164 £1,333 £16,211 12.2 yrs £10,458
7 kW 7085 kWh 5172 kWh 1913 kWh £1,364 £191 £1,556 £18,038 11.6 yrs £13,076
8 kW 8097 kWh 5911 kWh 2186 kWh £1,559 £219 £1,778 £19,865 11.2 yrs £15,694

Assumptions: south-facing, sensible tilt; self-use shares from site rules; export at 10p baseline. Costs: panels £/kW = 1,827, battery £/kWh = 700.

10 kWh battery 5 kW example → Annual benefit: £1,128, Upfront: £16,134, Break-even: 14.3 yrs
System Annual output Self-use Exported Bill saving Export income Annual benefit Upfront cost Break-even 20-year net
2 kW 2024 kWh 1518 kWh 506 kWh £401 £51 £451 £10,654 23.6 yrs £-1,631
3 kW 3036 kWh 2277 kWh 759 kWh £601 £76 £677 £12,481 18.4 yrs £1,053
4 kW 4049 kWh 3036 kWh 1012 kWh £801 £101 £902 £14,307 15.9 yrs £3,737
5 kW 5061 kWh 3796 kWh 1265 kWh £1,001 £127 £1,128 £16,134 14.3 yrs £6,422
6 kW 6073 kWh 4555 kWh 1518 kWh £1,202 £152 £1,353 £17,961 13.3 yrs £9,106
7 kW 7085 kWh 5314 kWh 1771 kWh £1,402 £177 £1,579 £19,788 12.5 yrs £11,790
8 kW 8097 kWh 6073 kWh 2024 kWh £1,602 £202 £1,804 £21,615 12.0 yrs £14,475

Assumptions: south-facing, sensible tilt; self-use shares from site rules; export at 10p baseline. Costs: panels £/kW = 1,827, battery £/kWh = 700.

13.5 kWh battery 5 kW example → Annual benefit: £1,144, Upfront: £18,584, Break-even: 16.2 yrs
System Annual output Self-use Exported Bill saving Export income Annual benefit Upfront cost Break-even 20-year net
2 kW 2024 kWh 1559 kWh 466 kWh £411 £47 £458 £13,104 28.6 yrs £-3,949
3 kW 3036 kWh 2338 kWh 698 kWh £617 £70 £687 £14,931 21.7 yrs £-1,198
4 kW 4049 kWh 3117 kWh 931 kWh £822 £93 £915 £16,757 18.3 yrs £1,553
5 kW 5061 kWh 3897 kWh 1164 kWh £1,028 £116 £1,144 £18,584 16.2 yrs £4,303
6 kW 6073 kWh 4676 kWh 1397 kWh £1,234 £140 £1,373 £20,411 14.9 yrs £7,054
7 kW 7085 kWh 5455 kWh 1630 kWh £1,439 £163 £1,602 £22,238 13.9 yrs £9,804
8 kW 8097 kWh 6235 kWh 1862 kWh £1,645 £186 £1,831 £24,065 13.1 yrs £12,555

Assumptions: south-facing, sensible tilt; self-use shares from site rules; export at 10p baseline. Costs: panels £/kW = 1,827, 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.

Before you request quotes in Harlow

Use the numbers above to sanity-check installer quotes. The main things to compare are system size, battery assumptions, payback claims, MCS certification, DNO paperwork and export assumptions.

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Seasonal solar output in CM18

Monthly generation per kilowatt of solar panels

kWh 39 Jan 53 Feb 86 Mar 113 Apr 120 May 123 Jun 123 Jul 111 Aug 95 Sep 68 Oct 46 Nov 35 Dec
Best month Worst month Winter (Dec–Feb) Other months

Winter output: 49.9% of an average month (Dec–Feb)

Best / worst month: Jul / Dec

These figures show output per kilowatt (kW) of panels installed. In winter, a 1 kW system here produces about 42 kWh per month; the average month produces around 84 kWh. So a typical 4 kW home system would generate roughly 168 kWh in winter, or 337 kWh in an average month.

Your Area at a Glance

Your Electricity Rate
26.38p/kWh
Daily Fixed Charge
53.94p/day
Local Sunshine
1012kWh/kW
A 1 kW system generates ~1012 kWh per year. A typical home uses ~2,700 kWh per year.
Typical System Size
4.0kW
For houses & bungalows in this area

Local Property Data

Property Types

Houses: 66% • Flats: 27% • Bungalows: 4% Based on 6,703 properties

Coverage

Harlow (100%)

Areas Covered

Bush Fair, Latton Bush & Stewards, Passmores, Little Parndon & Town Centre, Sumners & Kingsmoor, Great Parndon, Epping West & Rural, North Weald Bassett

Data Sources & Assumptions

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

Electricity rates: Ofgem price cap, Q3 2026

Installation costs: DESNZ/MCS data, March 2026 (TIC)

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.