Case Study
See the difference
in a real home
"

We were spending a fortune heating rooms we barely used. Now every room warms up exactly when we need it. The kids' rooms are cosy for bedtime, the living room's perfect for the evening, and the spare room only heats up when we have guests. Our gas use dropped and has stayed down.

40%
Energy reduction
£965
Annual saving
Semi-detached
Property type
22 TRVs
Smart valves installed
ZW
The founder’s own home · 4-bedroom semi-detached
Glasgow, G12
Cutting consumption is your price hedge
Same home. Same system. The war in Ukraine drove UK gas from under 3p to over 11p per kWh. The gas this home no longer burns was worth ~£747 in 2022, ~£1,864 at the 2023 peak and ~£965 in 2025: one reduction, whose value rises with whatever prices do next.
Gas used each year kWh — cut by 40% and held there Before zoning Installation year With zoning
015k30k45k202040,499202136,388202220232024202524,2922020 level
What gas would have cost without zoning £ per year at that year’s gas price (below); label = saving Without zoning With zoning
£0£1k£2k£3k£4k£5k−£7472022−£1,8642023−£9642024−£9652025 Gas unit price that year p/kWh 0p14p6.85p11.69p6.36p5.95p
Show the figures
YearUnit rateGas chargeskWh usedAnnual saving
2020 baseline2.71p/kWh£1,17540,499—
2021 zoning added Nov 20212.87p/kWh£1,14536,388—
2022 first full year6.85p/kWh£1,90429,583£747
2023 price spike11.69p/kWh£2,28424,546£1,864
20246.36p/kWh£1,80125,349£964
2025 latest5.95p/kWh£1,62624,292£965

Baseline = 2020 (40,499 kWh), the last full year before installation. The zoning system was added in November 2021, so 2021 is shown as the installation year and not used as the baseline. Annual saving = kWh reduction from that baseline × that year’s average unit rate (kWh-weighted). This is the pure consumption saving: the gas not burned, valued at prevailing prices. The cost chart is gas used × unit rate only, without standing charges, so it is lower than the gas charges in the table, which include standing charges and VAT as billed. Every figure comes from the monthly gas statements for this home (Pure Planet to April 2021, Octopus Energy since). The same gas not burned was worth ~£465/yr at 2021 rates and ~£1,864/yr at 2023 peak rates.