Drive from Loughton up to Epping and you cross from one electricity network licence area into another. Both belong to UK Power Networks, both towns are in Epping Forest district, and the people who live there pay the same council, yet on UKPN’s own boundary data Loughton’s town centre is on its London network and Epping’s on its Eastern one. For solar panels and a battery that difference is mostly paperwork, but it is a good place to start understanding how Essex homes connect. Our hub on solar panels across Essex covers grants and planning by council; this guide is about the wires.
Before UK Power Networks, the cables and lines in Essex were managed by Eastern Electricity and London’s network by London Electricity. Both are now part of UKPN, which is why every Essex connection we deal with goes to the same company, whichever licence area your street falls in.
Six towns, three licence areas
| Town | Council | Town centre’s licence area | Nearest other area, from the town-centre point |
|---|---|---|---|
| Loughton | Epping Forest | UKPN London | Eastern, about 1.2 km |
| Epping | Epping Forest | UKPN Eastern | London, about 3.8 km |
| Basildon | Basildon | UKPN Eastern | South Eastern, about 9.1 km |
| Harlow | Harlow | UKPN Eastern | London, about 10.4 km |
| Brentwood | Brentwood | UKPN Eastern | London, about 12.2 km |
| Chelmsford | Chelmsford | UKPN Eastern | London, about 26.9 km |
Licence areas from UK Power Networks’ boundary data; distances measured on NESO’s licence-area boundaries.
Chelmsford is deep inside the Eastern area; Loughton sits so close to the edge that parts of the town may be on either network. The South Eastern area nearest Basildon, across the Thames, is UKPN’s too. If you want certainty for your own address, the code on your electricity bill contains a Distributor ID: the Energy Networks Association lists 10 as Eastern England and 12 as London, both UK Power Networks. Our Loughton solar panels and solar panels in Epping pages cover the two towns either side of the line.
G98 or G99: the size that changes the paperwork
The connection rules are national, set by the Energy Networks Association. Type-tested equipment up to and including 16 A per phase, 3.68 kW, is notified under G98, before commissioning or within 28 days after. Anything larger needs a G99 application approved before work starts. The line falls close to a typical home system: a 4 kW inverter runs at about 17.39 A, so it is just over and goes down the G99 route. The installer works out which applies to the whole system and files it; you should not have to fill in a form.
UK Power Networks makes two commitments that matter here. It says it automatically approves applications where the installation’s maximum export, after any export limitation scheme, is under 5 kW, which covers most home systems. And it says that if your supply can take the new equipment there is nothing for you to pay it; only where its teams need to upgrade the supply do cost and timing vary by project. Approved installers file the forms through its Smart Connect portal, which handles both G98 and G99 for solar PV and battery storage.
What the network’s reliability figures say
Ofgem publishes reliability figures for every licence area. For 2024/25, as reported (Ofgem notes they are not final), UKPN’s Eastern area recorded about 44.6 supply interruptions per 100 customers and about 32.5 minutes lost per customer over the year, down from about 46.2 and 35.6 the year before. Its London area recorded about 11.2 and 10.5. Across all 14 licence areas in Great Britain the figures were about 39.7 and 35.1.
Those are licence-area averages, planned and unplanned work included, not a forecast for your street, and they do not make a battery a necessity anywhere in Essex. They do answer a question we hear often: on average, customers on either network lost well under an hour of supply over the year.
The plain truth about batteries and power cuts
A standard grid-tied battery is not a backup supply. When the grid goes down, the solar inverter and the battery shut down too, and the house goes dark like its neighbours. Backup is possible, but it has to be designed in: extra switching, normally for chosen circuits, at extra cost.
Even with backup, winter limits what it can do. PVGIS puts a 4 kWp due-south array in Chelmsford at about 145 kWh in December, roughly 4.7 kWh a day (our arithmetic), against Ofgem’s typical household use of about 6.8 kWh a day. A December outage is covered by whatever the battery held beforehand, not by the roof. If you work from home in Brentwood or rely on powered medical equipment in Basildon, say so at survey and we will tell you whether backup is worth paying for. See our pages on solar panels in Chelmsford and solar panels in Basildon for each town’s generation figures.
Sizing a battery is a separate question
The network decides the paperwork, not the battery size. The Energy Saving Trust says there is no exact formula, describes a typical home system as perhaps 10 kWh and puts a 5 kWh system at around £4,600; our guide to what size home battery you need shows how to size one to your evening use. If you are considering storage without panels, battery storage without solar panels sets out when that makes sense. For a town on the boundary, our page on battery storage in Loughton covers the local detail.
What to have ready for a survey
Bring a recent electricity bill, so the Distributor ID and your usage are both to hand, a note of where your meter and consumer unit are, and whether anything in the house must keep running in a cut. We are MCS-certified for solar PV and battery storage, with certification held via NAPIT (member 73495), and the G98 or G99 paperwork is the installer’s job, not yours. If your supply needs upgrading first, we will tell you before you commit.
Sources: UK Power Networks, licence boundaries open data (town-centre point checks), Our history, Solar and storage: cost, time and what’s involved, and Smart Connect; NESO, GIS boundaries for GB DNO licence areas (May 2024); Energy Networks Association, Find my network operator and EREC G98 Issue 2; Ofgem, RIIO-2 Electricity Distribution annual report 2024 to 2025 and supplementary datafile (reliability), and typical domestic consumption values from 1 July 2026; PVGIS 5.3, European Commission Joint Research Centre (PVGIS-SARAH3 2005–2023; Chelmsford monthly run, 15 October 2026); Energy Saving Trust, Battery storage (updated 19 August 2026). Read 15 October 2026. Daily figures are our arithmetic.