In December, a 4 kWp solar array facing due south near Chingford Green makes about 142 kWh, according to the European Commission’s PVGIS 5.3 model. In June the same array makes about 482 kWh. Over a year it comes to about 4,011 kWh, but the year is far from even, and that unevenness decides how much a battery can do for you.
This guide goes through the months for a Chingford roof, what changes on east- and west-facing slopes and near the forest, and what it means for sizing. For the roof itself, planning in the Chingford Green conservation area and the cost benchmarks, see our page on solar panels in Chingford.
The Chingford year, month by month
PVGIS’s monthly averages for a 4 kWp south-facing array at our Chingford point (51.63, 0.005), building-mounted, 35° tilt and 14% losses, on the 2005–2023 satellite record:
| Month | kWh in the month | kWh a day |
|---|---|---|
| January | 159 | 5.1 |
| February | 210 | 7.5 |
| March | 340 | 11.0 |
| April | 448 | 14.9 |
| May | 475 | 15.3 |
| June | 482 | 16.1 |
| July | 486 | 15.7 |
| August | 441 | 14.2 |
| September | 376 | 12.5 |
| October | 267 | 8.6 |
| November | 185 | 6.2 |
| December | 142 | 4.6 |
On our arithmetic, November to February together make about 696 kWh, roughly 17% of the year, while May to August make about 1,884 kWh, roughly 47%. These are figures for an unshaded roof, not a survey result or a promise of what any system will produce.
The sunshine behind the curve
Hampstead, the nearest Met Office climate station to Chingford, averaged about 1,559 hours of sunshine a year over 1991–2020, from about 200 hours in July to about 54 in December; Greenwich Observatory, the next nearest, averaged about 1,526. Output follows the same shape. Panels still generate from diffuse light under cloud, which is why Chingford’s December total is low rather than nil; our guide to whether solar panels work on cloudy days explains why.
East and west slopes lose more in winter
Across Chingford’s five wards 34.6% of households live in semi-detached houses, 49.0% in Endlebury (Census 2021, our sums), and not every semi has a slope facing south. We ran PVGIS for the same Chingford point with the array facing due west and due east. Facing west: about 3,126 kWh a year, 451 kWh in June and 61 kWh in December. Facing east: about 3,226 kWh a year, 462 kWh in June and 59 kWh in December.
In June an east or west roof gives up only about 4% to 7% against south. In December it makes less than half as much, about 13% of its own June output (our arithmetic). So on an east- or west-facing Chingford roof, winter contributes very little, and the case for panels rests on the months from spring to early autumn.
The forest edge
Chingford sits on the edge of Epping Forest, kept as public open space since the Epping Forest Act 1878 with the City of London Corporation as Conservators, and trees along the forest edge can shade nearby roofs. PVGIS calculates its horizon from terrain data, so its figures leave out trees and neighbouring buildings. In winter the sun stays low, and a tree that clears an E4 roof in June can shade it in December, cutting further into the weakest month. That is why we measure shading on site rather than rely on a model.
What it means for a battery
Ofgem’s typical household uses 2,500 kWh a year, about 6.8 kWh a day on average (our arithmetic). An average June day on a south-facing Chingford roof makes about 16.1 kWh, more than twice that, much of it while people are out; an average December day makes about 4.6 kWh, less than the household uses. A battery moves daytime surplus into the evening. In summer there is surplus to move; in December there is little or none. No battery makes a home self-sufficient in a Chingford winter.
The Energy Saving Trust says a typical home system might be 10 kWh, puts a 5 kWh system at around £4,600 and says there is no exact formula for sizing. With about 16 kWh made on a June day, a 5 kWh battery could fill from the roof on a sunny day if little is used at home in daylight; with 4.6 kWh made in December, part of it used as it is generated, it will rarely fill from the panels.
The practical test is your own evening use between April and September, when a south-facing Chingford roof averages between about 12.5 and 16.1 kWh a day on PVGIS’s figures. Read it from your smart meter or your bills and size the battery to that, not to December. With 63.5% of households across the five Chingford wards owning their home (Census 2021, our sums), most can make that call without waiting on a landlord. Our guide to what size home battery you need starts from your own readings, and our page on battery storage in Chingford covers where a unit fits in an E4 semi.
One year is not the average
PVGIS gives the south-facing Chingford array a year-to-year swing of about ±158 kWh around its 4,011 kWh average, and December alone varies by about ±28 kWh. A dull December can make noticeably less than 142 kWh, a bright one more. Design for the average and treat any single month as a range. Our solar panels in North London hub covers the boroughs around Waltham Forest.
Sources: PVGIS 5.3 (European Commission Joint Research Centre), PVcalc, PVGIS-SARAH3 2005–2023, DEM-calculated horizon, 4 kWp, 35° tilt, 14% losses, building-mounted, at 51.63, 0.005: due south run 15 October 2026 and re-run 18 October 2026, due west and due east run 18 October 2026 (percentages our arithmetic); Met Office, Hampstead and Greenwich Observatory location-specific long-term averages, 1991–2020; ONS Census 2021 via Nomis, TS044 for Chingford’s five 2022 wards (our sums); City of London Corporation, Epping Forest; Ofgem, Typical Domestic Consumption Values (from 1 July 2026); Energy Saving Trust, Battery storage (updated 19 August 2026).