Isle of Man · Solar evidence for home decisions
Solar panel generation on the Isle of Man
Explore how much electricity an example system could generate—and how its direction, tilt and mounting change the result. Start with the seasonal pattern, then ask for a design for your own home.
PVGIS 5.3 · SARAH3 solar data, 2005–2023 · imported 21 September 2026. One regional example point near Douglas. Not a roof survey, current measurement or guaranteed output.
Explore a system scenario
Every scenario uses crystalline-silicon panels, 14% system losses and PVGIS’s terrain horizon. The default is a south-facing, 35° system with free-standing ventilation. These inputs are examples, not facts about any advertised property.
kWp is the panels’ rated peak capacity; kWh is the electricity generated over time. Size examples scale a 1 kWp model, holding every other input fixed. They do not determine usable roof area, inverter sizing or an appropriate installation size.
4,135 kWhmodelled average per year
Mayhighest average month
10.0%of yearly output in Dec–Feb
Showing 4 kWp · South-facing · 35° tilt · regional example near Douglas.
Chart: average monthly electricity in kWh. Full values and units are in the accessible table.
| Month | Electricity kWh/month | Daily average kWh/day | Year-to-year variation, kWh | Panel-plane sunlight kWh/m²/month |
|---|---|---|---|---|
| January | 120 | 3.9 | 22 | 35.2 |
| February | 202 | 7.2 | 35 | 59.0 |
| March | 352 | 11.4 | 42 | 102.8 |
| April | 495 | 16.5 | 58 | 147.3 |
| May | 569 | 18.4 | 50 | 172.2 |
| June | 549 | 18.3 | 56 | 169.1 |
| July | 532 | 17.2 | 57 | 164.8 |
| August | 479 | 15.4 | 43 | 146.8 |
| September | 369 | 12.3 | 36 | 111.8 |
| October | 239 | 7.7 | 32 | 71.5 |
| November | 138 | 4.6 | 24 | 41.3 |
| December | 91 | 2.9 | 17 | 27.1 |
Variation is the model’s standard deviation across historical years, not an error bar, likely range or prediction. Annual variation for this example: 141 kWh. Monthly averages can differ from a year’s actual output; rounded monthly totals may not sum exactly to the annual figure.
Compare direction, tilt and mounting
All six use the same regional point and system-loss assumption. Only the named setting changes. “Free-standing” is PVGIS’s well-ventilated mounting model; “building-integrated” restricts airflow behind panels. Real roof-mounted systems can fall between these cases. The selected angles are examples, not an optimisation or recommendation.
| Scenario | Annual output kWh | Relative to south 35° | December–February kWh |
|---|---|---|---|
| South-facing · 35° tilt | 4,135 | 100.0% | 413 |
| East-facing · 35° tilt | 3,140 | 75.9% | 201 |
| West-facing · 35° tilt | 3,301 | 79.8% | 201 |
| South-facing · 15° tilt | 3,850 | 93.1% | 304 |
| South-facing · 60° tilt | 3,965 | 95.9% | 481 |
| South-facing · 35° · building-integrated | 4,016 | 97.1% | 405 |
Generation is not the same as financial savings. This comparison does not model batteries, export limits, electricity tariffs, self-consumption or installation costs.
Use this when comparing homes
- Ask for monthly generation estimates with the installer’s assumptions attached.
- Compare the seasonal pattern with your household’s actual electricity use.
- Check roof rights, condition, shade, panel layout and connection arrangements on site.
- If panels already exist, ask for their recorded generation and ownership documents.
What the model does not know
The solar-radiation grid is approximately 5 km, while terrain-horizon modelling uses separate elevation data. The selected point is not an island-wide average or a measurement for every parish. Coordinates: 54.15°, -4.48°.
We have not modelled a property’s roof, nearby trees, chimneys or neighbouring buildings. This is not a property score, a climate forecast, planning approval or a performance guarantee.
Sources, assumptions and downloadable data
Source: European Commission Joint Research Centre, PVGIS 5.3, using the PVGIS-SARAH3 radiation database and the returned 2005–2023 period. The meteorological database reported by the API is ERA5. Imported 2026-09-21; this does not make the historical data a current observation. Independent presentation, without provider endorsement.
Read the PVGIS methodology (opens in a new tab) · PVGIS reuse conditions (opens in a new tab) · NASA seasonal climate context. NASA figures use a different period and measure incoming horizontal solar energy; do not combine them with PVGIS panel generation as though they were the same measure.
Original source response for each scenario
- South-facing · 35° tilt — 1 kWp source model (opens in a new tab)
- East-facing · 35° tilt — 1 kWp source model (opens in a new tab)
- West-facing · 35° tilt — 1 kWp source model (opens in a new tab)
- South-facing · 15° tilt — 1 kWp source model (opens in a new tab)
- South-facing · 60° tilt — 1 kWp source model (opens in a new tab)
- South-facing · 35° · building-integrated — 1 kWp source model (opens in a new tab)
The controls run entirely in your browser. They do not send addresses, property coordinates or choices to PVGIS. Downloads contain public regional model outputs only. Existing provider rooftop maps remain external links and are not copied.