Warm Home Optimiser
The best next move for your home and budget — geared to the Warm Homes 0% loan. Enter real quotes to sharpen the payback; it will also tell you when you're done.
Your limiting factor
Single-phase supply
Your single-phase supply caps how much you can charge, export, and run at once — three-phase is the unlock behind the bigger moves.
Best move now
Switch to a smart EV tariff
£0 → saves £350/yr · 0.0yr payback · on the 0% loan you're +£350/yr from year one.
Your home
0 = full
Your energy
0 = no gas
0 = no EV
blank = no gas boiler
Your budget
0 = Warm Homes
Off-peak 7p · export 13p · gas 6.2p. All figures modelled — adjust any input and the plan updates live.
Your options, ranked
Switch to a smart EV tariff
BestFree. Charges your EV at ~7–8p overnight instead of the day rate.
Saves
£350/yr
Payback
0.0y
On loan
+£350/yr
Add a 10 kWh battery
Saves
£452/yr
Payback
12.2y
On loan
−£98/yr
Add 5.0 kWp solar PV
Export income needs MCS certification — otherwise only self-use counts.
Saves
£407/yr
Payback
16.0y
On loan
−£243/yr
Replace gas boiler with a heat pump
Best deferred until your boiler dies, so the grant offsets a spend you were going to make anyway.
after £7,500 grant
Saves
£98/yr
Payback
45.9y
On loan
−£352/yr
Raise export limit (G99 / DNO)
UnlockerOnly worth it if your solar/battery is actually capped by the export limit — enter your DNO quote to check.
Unlocks: export
Saves
—
Payback
—
On loan
−£200/yr
Upgrade to three-phase supply
UnlockerAn enabler more than a saver — it unblocks a bigger battery, higher export and a heat pump running alongside the EV. Enter your DNO quote.
Unlocks: higher charge rate, higher export ceiling, run heat pump + EV + battery together
Saves
—
Payback
—
On loan
−£600/yr
"On loan" is your annual saving minus the loan repayment — positive means you're up from year one. Ranked by payback; blocked and zero-value moves sink to the bottom.