Glamorgan
Solar panels in Mountain Ash, sized to your roof.
About 6,030 kWh a year from 12 panels in Mountain Ash, £6,360 installed, with your system designed on a free 30-minute video call.
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or call 07782 219224
- Free 30-minute video design call
- Priced before anyone visits
- Installed by our MCS-certified, fully insured teams
What a roof in Mountain Ash can generate
From 26.3 kWh per kWp in December to 123.1 in May: a roof in Mountain Ash makes 4.7 times as much in its best month as in its darkest, and 948 kWh per kWp across the year.
Generation per kWp, month by month
Show the monthly figures
| Month | kWh/kWp |
|---|---|
| January | 28.8 |
| February | 47.3 |
| March | 83.9 |
| April | 113 |
| May | 123 |
| June | 119 |
| July | 119 |
| August | 104 |
| September | 89.1 |
| October | 56.7 |
| November | 37.5 |
| December | 26.3 |
Source: PVGIS v5.2 (European Commission JRC), SARAH3 database, 1 kWp, 14% system loss, 35 degree pitch, due south, checked September 2026.
Against Great Britain as a whole: Mountain Ash makes 948 kWh per kWp a year, and the mean of our 85 county PVGIS estimates (our GB average) is 925, so Mountain Ash is 2% above it.
How Mountain Ash compares
Small towns rarely get published solar figures, so here are the numbers for Mountain Ash. It is one of 32 Glamorgan towns we track, and it ranks 27th of 32 for solar yield, a town of 13,405 people in the House of Commons Library settlement data. PVGIS gives its roofs 948 kWh per kWp a year, 2.60 peak sun hours a day averaged across the seasons, and the standard 12 panel model turns that into £858 of year one benefit, £247 of it from your own generation and £611 from export at 12p.
These are starting numbers, not a quote. The calculator below opens on Mountain Ash's own PVGIS figure; change the panels, the battery or the export rate and it reruns. The design call replaces every assumption with your roof and your bills.
Mountain Ash sits within Rhondda Cynon Taf, its local planning authority, and the House of Commons Library classes it as a small town.
The charger is in the installed price but left out of payback: charging savings depend on your mileage and tariff, which the design call models properly.
Your real roof and usage, worked through on a free 30-minute video call. Use the full form or leave three details below.
Price this for your roof
Three details. We call or text within one working day to book your free 30-minute design call, on video or by phone if you prefer.
Modelled for Mountain Ash at 51.67952, -3.3782 on PVGIS data, with imports valued at 26.32p/kWh and solar at £1,000 per kWp installed. Sources and assumptions: help page.
Connecting solar to the Mountain Ash network
Mountain Ash sits in National Grid Electricity Distribution's South Wales licence area, so NGED is the network operator (DNO) any solar panels or battery here are registered with.
G98 is the simple route. If the inverter, plus any battery, stays at or under 3.68kW per phase, NGED only has to be told within 28 days after the system is commissioned.
A bigger inverter or battery output needs a G99 application in advance. NGED's guaranteed standards give 45 working days for a low voltage generation quotation, with £80 paid for each working day late.
Sources: NESO DNO licence areas (3 May 2024); NGED, guaranteed standards of performance table, checked 25 September 2026. G98 vs G99, explained.
Adding a heat pump or an EV charger in Mountain Ash
A heat pump in Mountain Ash
Solar and a heat pump pull in opposite directions through the year: Mountain Ash's roofs make 890 kWh from November to February on a 12-panel system, and 2,960 kWh from May to August. The heating season leans on the grid, so off-peak rates do the heavy lifting.
The Boiler Upgrade Scheme, open in England and Wales, takes £7,500 off an air source or ground source heat pump, or £2,500 off an air-to-air unit. Homes on oil or LPG with no mains gas get £1,500 more until March 2027 (gov.uk, checked 28 September 2026).
Charging an EV in Mountain Ash
A 12-panel roof in Mountain Ash makes about 780 kWh in May. A typical home uses around 70 kWh of that in daylight (the calculator's typical-use settings), which leaves most of the month's output for an EV or for export.
Renters and flat owners with private off-street parking can get 75% off a chargepoint and its installation, up to £500 per socket, until 31 March 2027 (gov.uk, checked 28 September 2026). The calculator above adds a 7.4kW smart charger from £1,100 installed.
The packages, priced before anyone visits
Every system is designed around your roof on the free call before anything is fitted.
Solar panel servicing and repair in Mountain Ash
Guidance is nationwide, so the benchmarks hold in Mountain Ash: repair costs, service scope, and when the inverter is the real fault.
Mountain Ash solar questions
What could a roof in Mountain Ash generate?
PVGIS puts a roof in Mountain Ash at 948 kWh per kWp a year, 2.60 peak sun hours a day averaged across the seasons. A 12-panel, 6.36 kWp system makes about 6,030 kWh a year, most of it between April and September.
What would 12 solar panels cost in Mountain Ash?
£6,360 for 12 panels (6.36 kWp), the same as in every other place we cover, because solar is priced at £1,000 per kWp installed rather than by area. A battery adds its own installed price on top. Where Mountain Ash differs is output: about 6,030 kWh a year from that system.
Do I need permission from the DNO for solar in Mountain Ash?
Usually not in advance. NGED, the network operator for Mountain Ash, only needs a G98 notification within 28 days of commissioning for systems up to 3.68kW per phase. Bigger inverter or battery outputs need G99 approval first. NGED's guaranteed standards give 45 working days for a low voltage generation quotation, with £80 paid for each working day late. "See our DNO explainer.
How much would export pay on a system in Mountain Ash?
It is exported. With typical use and no battery, about 5,093 kWh of the 6,030 kWh a 12-panel system makes in Mountain Ash goes to the grid, around £611 a year at 12p. A battery keeps more of it for the evening; the export rates table shows what suppliers pay.
Do solar panels work in winter in Mountain Ash?
Yes, at a lower level. PVGIS gives Mountain Ash 26.3 kWh per kWp in December and 28.8 in January, so a 12-panel system makes about 170 kWh and 180 kWh in those months, against 780 kWh in May. Winter output mostly covers daytime use rather than exporting.
How Mountain Ash compares with its neighbours
Same satellite dataset, same assumptions, so the differences are real geography rather than modelling noise.
| Town | kWh per kWp a year | vs Mountain Ash |
|---|---|---|
| Mountain Ash | 948 | this town |
| Aberdare | 940 | −8 kWh |
| Porth | 961 | +13 kWh |
| Rhondda | 882 | −66 kWh |
| Merthyr Tydfil | 942 | −6 kWh |
| Tonypandy | 956 | +8 kWh |
| Treorchy | 925 | −23 kWh |
Each row is a PVGIS v5.2 run at that town's centre with the same settings. Treat gaps of a few kWh as noise and gaps over about 30 kWh per kWp as real differences in sunshine.
Also for Mountain Ash: Solar panels in Mountain Ash from OVO Solar & Battery
Also near Mountain Ash
See a number before you speak to anyone
Answer a few questions about your roof and usage and see an instant solar and battery estimate. No email needed to see the result.
Further reading for Mountain Ash
Sourced, dated and written by us. The same ground we cover on your free call.
Solar panel types, and the four numbers that actually matter
TOPCon, HJT and back contact decoded, plus the four numbers worth comparing.
Read the guide →Tesla Powerwall 3 against the alternatives, and where each one wins
The strongest single box in the market, and the houses it is still wrong for.
Read the guide →Charging an EV from your own solar
Every surplus kWh is 3.6 to 5 miles. Whether that beats a 7p overnight rate is arithmetic.
Read the guide →What are the disadvantages of a heat pump? Six honest ones
Six real disadvantages, worth planning around rather than a reason to rule one out.
Read the guide →Why tariff choice moves payback more than kit choice
Identical kit, five times the export income. The tariff decision worked through with August 2026 rates.
Read the guide →What MCS certification actually is, and why your export payments depend on it
The badge that decides whether your solar earns export payments. It cannot be added later.
Read the guide →Get my free quote
Takes about two minutes. We call or text within one working day to book your free 30-minute video design call at a time that suits you. We design it around your roof and your numbers, and our MCS-certified, fully insured installation teams install it.