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Solar panel cost in Portsmouth (PO4)

See realistic solar installation costs, savings and payback for PO4 (Portsmouth) 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

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
9.1 years
After this, it's pure profit
Upfront Cost
£8,139
What you pay to get started
Annual Benefit
£898
What you save every year
Profit Over 25 Years
£14,311
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

In Southern, the current unit rate is 26.42p/kWh with a 49.70p/day standing charge. Your postcode’s south-facing sunshine yield is 1084 kWh/kW — 83 above the regional median (1001).

Read the full story

A typical roof here lands around 5.0 kW, with most eligible homes comfortably fitting within 3–6 kW. Each kilowatt of panels produces roughly 1084 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
49.7p/day
Sunshine yield (south)
1084 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: £898, Upfront: £8,139, Break-even: 9.1 yrs
System Annual output Self-use Exported Bill saving Export income Annual benefit Upfront cost Break-even 20-year net
2 kW 2168 kWh 867 kWh 1301 kWh £229 £130 £359 £3,256 9.1 yrs £3,928
3 kW 3252 kWh 1301 kWh 1951 kWh £344 £195 £539 £4,883 9.1 yrs £5,893
4 kW 4336 kWh 1734 kWh 2602 kWh £458 £260 £718 £6,511 9.1 yrs £7,857
5 kW 5420 kWh 2168 kWh 3252 kWh £573 £325 £898 £8,139 9.1 yrs £9,821
6 kW 6504 kWh 2602 kWh 3902 kWh £687 £390 £1,078 £9,767 9.1 yrs £11,785
7 kW 7588 kWh 3035 kWh 4553 kWh £802 £455 £1,257 £11,394 9.1 yrs £13,749
8 kW 8672 kWh 3469 kWh 5203 kWh £916 £520 £1,437 £13,022 9.1 yrs £15,713

Assumptions: south-facing, sensible tilt; self-use shares from site rules; export at 10p baseline. Costs: panels £/kW = 1,628, battery £/kWh = 700.

3 kWh battery 5 kW example → Annual benefit: £1,076, Upfront: £10,239, Break-even: 9.5 yrs
System Annual output Self-use Exported Bill saving Export income Annual benefit Upfront cost Break-even 20-year net
2 kW 2168 kWh 1301 kWh 867 kWh £344 £87 £430 £5,356 12.4 yrs £3,252
3 kW 3252 kWh 1951 kWh 1301 kWh £516 £130 £646 £6,983 10.8 yrs £5,928
4 kW 4336 kWh 2602 kWh 1734 kWh £687 £173 £861 £8,611 10.0 yrs £8,605
5 kW 5420 kWh 3252 kWh 2168 kWh £859 £217 £1,076 £10,239 9.5 yrs £11,281
6 kW 6504 kWh 3902 kWh 2602 kWh £1,031 £260 £1,291 £11,867 9.2 yrs £13,957
7 kW 7588 kWh 4553 kWh 3035 kWh £1,203 £304 £1,506 £13,494 9.0 yrs £16,633
8 kW 8672 kWh 5203 kWh 3469 kWh £1,375 £347 £1,722 £15,122 8.8 yrs £19,309

Assumptions: south-facing, sensible tilt; self-use shares from site rules; export at 10p baseline. Costs: panels £/kW = 1,628, battery £/kWh = 700.

5 kWh battery 5 kW example → Annual benefit: £1,165, Upfront: £11,639, Break-even: 10.0 yrs
System Annual output Self-use Exported Bill saving Export income Annual benefit Upfront cost Break-even 20-year net
2 kW 2168 kWh 1518 kWh 650 kWh £401 £65 £466 £6,756 14.5 yrs £2,564
3 kW 3252 kWh 2276 kWh 976 kWh £601 £98 £699 £8,383 12.0 yrs £5,596
4 kW 4336 kWh 3035 kWh 1301 kWh £802 £130 £932 £10,011 10.7 yrs £8,629
5 kW 5420 kWh 3794 kWh 1626 kWh £1,002 £163 £1,165 £11,639 10.0 yrs £11,661
6 kW 6504 kWh 4553 kWh 1951 kWh £1,203 £195 £1,398 £13,267 9.5 yrs £14,693
7 kW 7588 kWh 5312 kWh 2276 kWh £1,403 £228 £1,631 £14,894 9.1 yrs £17,725
8 kW 8672 kWh 6070 kWh 2602 kWh £1,604 £260 £1,864 £16,522 8.9 yrs £20,757

Assumptions: south-facing, sensible tilt; self-use shares from site rules; export at 10p baseline. Costs: panels £/kW = 1,628, battery £/kWh = 700.

7.5 kWh battery 5 kW example → Annual benefit: £1,192, Upfront: £13,389, 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 2168 kWh 1583 kWh 585 kWh £418 £59 £477 £8,506 17.8 yrs £1,028
3 kW 3252 kWh 2374 kWh 878 kWh £627 £88 £715 £10,133 14.2 yrs £4,167
4 kW 4336 kWh 3165 kWh 1171 kWh £836 £117 £953 £11,761 12.3 yrs £7,306
5 kW 5420 kWh 3957 kWh 1463 kWh £1,045 £146 £1,192 £13,389 11.2 yrs £10,445
6 kW 6504 kWh 4748 kWh 1756 kWh £1,254 £176 £1,430 £15,017 10.5 yrs £13,584
7 kW 7588 kWh 5539 kWh 2049 kWh £1,463 £205 £1,668 £16,644 10.0 yrs £16,723
8 kW 8672 kWh 6331 kWh 2341 kWh £1,673 £234 £1,907 £18,272 9.6 yrs £19,861

Assumptions: south-facing, sensible tilt; self-use shares from site rules; export at 10p baseline. Costs: panels £/kW = 1,628, battery £/kWh = 700.

10 kWh battery 5 kW example → Annual benefit: £1,209, Upfront: £15,139, 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 2168 kWh 1626 kWh 542 kWh £430 £54 £484 £10,256 21.2 yrs £-580
3 kW 3252 kWh 2439 kWh 813 kWh £644 £81 £726 £11,883 16.4 yrs £2,630
4 kW 4336 kWh 3252 kWh 1084 kWh £859 £108 £968 £13,511 14.0 yrs £5,841
5 kW 5420 kWh 4065 kWh 1355 kWh £1,074 £136 £1,209 £15,139 12.5 yrs £9,051
6 kW 6504 kWh 4878 kWh 1626 kWh £1,289 £163 £1,451 £16,767 11.6 yrs £12,261
7 kW 7588 kWh 5691 kWh 1897 kWh £1,504 £190 £1,693 £18,394 10.9 yrs £15,471
8 kW 8672 kWh 6504 kWh 2168 kWh £1,718 £217 £1,935 £20,022 10.3 yrs £18,681

Assumptions: south-facing, sensible tilt; self-use shares from site rules; export at 10p baseline. Costs: panels £/kW = 1,628, battery £/kWh = 700.

13.5 kWh battery 5 kW example → Annual benefit: £1,227, Upfront: £17,589, 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 2168 kWh 1669 kWh 499 kWh £441 £50 £491 £12,706 25.9 yrs £-2,887
3 kW 3252 kWh 2504 kWh 748 kWh £662 £75 £736 £14,333 19.5 yrs £394
4 kW 4336 kWh 3339 kWh 997 kWh £882 £100 £982 £15,961 16.3 yrs £3,675
5 kW 5420 kWh 4173 kWh 1247 kWh £1,103 £125 £1,227 £17,589 14.3 yrs £6,957
6 kW 6504 kWh 5008 kWh 1496 kWh £1,323 £150 £1,473 £19,217 13.0 yrs £10,238
7 kW 7588 kWh 5843 kWh 1745 kWh £1,544 £175 £1,718 £20,844 12.1 yrs £13,519
8 kW 8672 kWh 6677 kWh 1995 kWh £1,764 £199 £1,964 £22,472 11.4 yrs £16,801

Assumptions: south-facing, sensible tilt; self-use shares from site rules; export at 10p baseline. Costs: panels £/kW = 1,628, 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 Portsmouth

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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Check what MCS certification means

Understand DNO, G98 and G99 export limits

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Share the first part of your postcode and a few basics. We’ll help you check whether system size, battery, export and paperwork assumptions look sensible before you commit to installer conversations.

This is a practical sanity-check request, not an instant quote promise. The Blue Ape quote route above remains available if you already want installer introductions.

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Insights for PO4

Figures below are tailored to PO4 — click through for full league tables.

Big-Roof Britain Rank #1746 of 2182
4.5 kWp (UK avg 5.1 kWp)
~10 panels (≈430 W)
Solar Payback Index Rank #147 of 2996
9.1 years (UK avg 10.8 years)
~£898 /yr • £8,139 upfront
Standing-Charge Drag Rank #619 of 2996
20.2% (UK avg 26.6%) drag on savings
£181 fixed • ~£898 /yr value
Aspect Penalty View ranking →
East −20.8% West −22.2%
Typical output loss versus a south-facing roof (lower is better)

Seasonal solar output in PO4

Monthly generation per kilowatt of solar panels

kWh 41 Jan 56 Feb 93 Mar 123 Apr 131 May 134 Jun 135 Jul 117 Aug 99 Sep 69 Oct 48 Nov 37 Dec
Best month Worst month Winter (Dec–Feb) Other months

Winter output: 49.3% 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 45 kWh per month; the average month produces around 90 kWh. So a typical 4 kW home system would generate roughly 178 kWh in winter, or 361 kWh in an average month.

Your Area at a Glance

Your Electricity Rate
26.42p/kWh
Daily Fixed Charge
49.70p/day
Local Sunshine
1084kWh/kW
A 1 kW system generates ~1084 kWh per year. A typical home uses ~2,700 kWh per year.
Typical System Size
5.0kW
For houses & bungalows in this area

Local Property Data

Property Types

Houses: 62% • Flats: 32% • Bungalows: 0% Based on 12,451 properties

Coverage

Portsmouth (100%)

Areas Covered

Milton, Eastney and Craneswater, Central Southsea, Charles Dickens, Baffins

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.

Compare nearby areas

Nearby in Southern

PO5 (Portsmouth)
≈1.6 km away
Local sunshine: ~1,084 kWh/kWp · +0% vs PO4
PO1 (Portsmouth)
≈2.0 km away
Local sunshine: ~1,084 kWh/kWp · +0% vs PO4
PO3 (Portsmouth)
≈2.6 km away
Local sunshine: ~1,096 kWh/kWp · +1% vs PO4
PO2 (Portsmouth)
≈3.0 km away
Local sunshine: ~1,096 kWh/kWp · +1% vs PO4
PO12 (Gosport)
≈5.8 km away
Local sunshine: ~1,072 kWh/kWp · -1% vs PO4
PO11 (Havant)
≈5.8 km away
Local sunshine: ~1,096 kWh/kWp · +1% vs PO4

Similar sunshine across the UK

BN6 (Mid Sussex)
~1,084 kWh/kWp · +0% vs PO4
TR19 (Cornwall)
~1,083 kWh/kWp · -0% vs PO4
SS5 (Rochford)
~1,083 kWh/kWp · -0% vs PO4