The short version
Salt words describe the land and the town’s history; they say nothing about a particular roof. Planning words decide whether you need an application. Grid words decide whether the installer tells the network operator afterwards or asks first. Scheme words decide who might help pay. Every term below links to the page that explains it in full.
Salt and ground
Words a Northwich buyer meets in the conveyancing file or on a listing, long before anyone talks about panels.
- Brine pumping
- Extracting salt by pumping water into the rock salt under mid-Cheshire and drawing it back up as brine. Where salt dissolved away underground, the surface could sink. Parliament legislated for the damage twice, in 1891 and in 1952. Subsidence and solar →
- The 1891 Act
- The Brine Pumping (Compensation for Subsidence) Act 1891, the earlier law, aimed at the Northwich area. It is history now, but it explains why subsidence appears in local paperwork at all. Subsidence and solar →
- Compensation District
- The single district set up under the Cheshire Brine Pumping (Compensation for Subsidence) Act 1952. A 1970 Lords written answer described it as taking in every part of Cheshire where brine subsidence had happened or might. It is a legal boundary, not a statement about any one street. Subsidence and solar →
- Cheshire Brine Subsidence Compensation Board
- The body the 1952 Act created to deal with claims inside the district. The Act was amended in 1964. Questions about a claim go to the Board or a solicitor, not to a solar firm. Buying a home with solar →
- Brine search
- A conveyancing search that buyers’ conveyancers commonly order for homes in the district, reporting on the brine-subsidence position. It is a paper check about the land, so it tells you nothing about whether the rafters can carry a solar array. Buying a home with solar →
- Subsidence-liftable
- Historic England’s wording for three listed Witton Street buildings: the Brunner Public Library (1909), the R.A.O.B. Hall (1911) and the former Post Office (1914). Each is a timber frame built so the whole structure could be raised and re-levelled if the ground beneath it dropped. Liftable timber buildings →
Buildings and planning
The planning words that decide whether panels need an application, a prior decision from the council, or nothing at all.
- Listed building
- A building on the National Heritage List for England. Panels on a listed house need planning permission and separate consent, whatever the roof looks like. Search the list by address before getting quotes. Liftable timber buildings →
- Listed Building Consent
- The consent needed for works that affect a listed building’s special interest. It sits alongside planning permission, so the Witton Street frames would need both before any panel went up. Liftable timber buildings →
- Conservation area
- A designated area of special architectural or historic interest. The council lists 96 across the borough; the ones around the town are Northwich, Marston - Lion Salt Works, Hartford, Davenham, Trent and Mersey Canal. On a house, a roof slope inside one stays permitted development; a wall or balcony facing the road does not. Conservation areas →
- Class A
- The part of the national rules covering panels on a house or block of flats and on buildings in its grounds. On a pitched roof the panels may stand no more than 0.2 m proud of the slope and must stay below the ridge; on a flat roof the limit is 0.6 m. Conservation areas →
- Class B
- Stand-alone panels in the grounds of a house: up to 9 m² without an application, with height limits and further conditions. Relevant on the larger plots in Hartford and Davenham. Off-gas homes →
- Prior approval
- A council decision required before certain permitted work starts. For homes in a conservation area, panels on a flat roof need one; pitched roof slopes do not. Conservation areas →
- SI 2026/896
- The amendment to the solar planning rules that took effect on 27 August 2026. It brought plug-in panels within the rules, changed the wall and balcony limits, and allows work under the old rules to finish until 26 August 2027. Renters and flats →
- Plug-in solar
- A small panel set that plugs into an ordinary socket. Under the amended rules it counts as solar PV and may not be fixed to timber walls, balconies, enclosures or timber-clad parts of a building, which matters on Northwich’s black-and-white timbered fronts. Liftable timber buildings →
- Lawful development certificate
- An optional council decision confirming that a project needed no planning application. Worth considering where the position is close, because a future buyer’s conveyancer may ask how the panels were approved. Buying a home with solar →
Output and data
How this guide measures a roof, and where the household figures come from.
- kWp
- Kilowatt peak: the rated size of an array under standard test light. Every output figure on this site is per 1 kWp, so multiply by the size on a quote. Output →
- Yield (kWh per kWp)
- Units of electricity a year for each kWp installed. The best case in our Northwich runs is a south-facing roof at 40°, at about 941 kWh per kWp a year; a 4 kWp array there would make roughly 3,764 kWh. Output →
- PVGIS
- The European Commission’s solar model. We ran it for central Northwich with 14% system losses and the PVGIS-SARAH3 sunlight data for 2005-2023. It assumes an unshaded roof. Data and sources →
- Pitch and direction
- Pitch is the roof angle from horizontal; direction is the way the slope faces. The roof check on the home page takes both and returns the PVGIS figure for that combination. Roof readiness check →
- Self-use and export
- Self-use is solar electricity used in the house as it is made; export is the rest, sent to the grid. In our south-facing runs, 69% of the year’s output arrives between April and September, which is why the summer surplus matters. Export and self-use →
- Ward (Census 2021)
- The council area unit the Census reports by. We use 7 wards, from the three Northwich wards to Shakerley and Davenham, Moulton & Kingsmead. A ward figure describes households, not roofs. Homes by ward →
- Installed cost per kW
- The government’s price measure, from certified installations. In 2025/26 the UK median for 0–4 kW was £1,595 per kW; the North West average was £1,800. It is a guide to fair prices, not a Northwich quote. Costs →
- Solar PV sites (local authority)
- The government’s count of solar sites by council, homes and businesses together. Cheshire West and Chester went from 5,759 at the end of 2019 to 11,740 at the end of 2025. Solar take-up locally →
Grid, paperwork and schemes
The names on the forms after the panels go up.
- Network operator
- The company that runs the local wires, which is not the company that bills you. SP Energy Networks describes its area as covering parts of Cheshire, so confirm yours with the Energy Networks Association postcode search before reading anyone’s connection rules. Grid connection →
- G98
- The route for small systems: up to 16 A per phase, which is 3.68 kW on a normal single-phase supply. The installer notifies the network operator within 28 days of commissioning. Grid connection →
- G99
- The route for anything over the G98 limit, including many solar-and-battery pairings. The application goes in and is answered before the work, so allow for it in the timetable. Grid connection →
- MCS
- The certification scheme for small renewable installers and products. An MCS certificate for the job is what an export tariff application asks for. Choosing an installer →
- SEG
- The Ofgem-run export scheme. Larger suppliers must offer an export tariff above 0p for MCS-certified systems of up to 50 kW with a meter that records export. The rate is set by each supplier. Export and self-use →
- Consumer code
- A code of practice, such as RECC or HIES, that MCS firms must belong to. It sets rules on deposits and contracts and gives a complaints route that is not the installer itself. Choosing an installer →
- Zero-rate VAT
- Installed solar panels and batteries on homes carry 0% VAT until 31 March 2027, then 5%. The rate applies to installation by the firm, not to kit you buy yourself. Costs →
- Warm Homes: Local Grant
- Funding for lower-income households in homes rated EPC D to G, run in west Cheshire by a council consortium until 31 March 2028. It can include solar panels; eligibility is checked through GOV.UK. Grants and schemes →
- Switch Together Solar
- The council’s group-buy, run in registration rounds with a reverse auction among certified firms. The council reports 473 people in the borough installed through the 2023 to 2025 rounds; the latest registration closed on 25 September 2026. Grants and schemes →
Words this guide avoids
We do not describe any Northwich street as safe or unsafe ground, because nothing published lets anyone say that about one address. We do not name a network operator for the town, because the postcode search is the reliable answer. For the full method see data and sources; if a definition here is out of date, tell us through the contact page.