The hardest part of decarbonising a home isn't the technology — it's knowing where to begin. The good news is that there are really only two front doors, and most people walk through one of them without ever seeing the other. Pick either and you're on a good path. Which door suits you comes down to one question: what are you likely to replace next?
Tap a door below to see where the journey goes from there.
Why the EV can come first
It surprises people, but a car can be the smartest opening move in a home energy plan. Buying an EV qualifies you for a special overnight tariff — a few cheap hours in the small hours designed for charging. The twist is that those cheap hours don't only power the car; anything you can shift to run overnight draws the same low rate — think dishwasher, washing machine, tumble dryer and immersion heater. The EV is the key; the cheap electricity is the door it opens.
There's one decision to make here. To unlock the very cheapest smart tariffs — the likes of Octopus Intelligent Go (IOG) — you need a smart charger the supplier can control, so it charges the car automatically in the cheapest half-hours. Our Top 5 home EV chargers covers the ones that do this well. Not fussed? A standard off-peak EV rate still saves plenty without one.
From there the path is open-ended. Add a home battery and you can hoard cheap overnight power to run the house through the day on cheap off-peak electricity — no solar required (our battery guide has five worth a look). Solar is then optional: with the battery already filling up cheaply overnight, panels become the cream on top rather than the main event.
Why solar comes first for everyone else
If a new car isn't on the cards, the roof is the natural place to start. Solar begins cutting bills the day it's switched on, and it sets up everything that follows. The usual sequence is solar first, then a battery to store the daytime surplus for the evening — or both together if the budget allows. An EV can still join later, and when it does, it brings that overnight rate with it.
The question that decides your first step: what are you replacing?
Replacing your car? Make it an EV — that's your front door, and it unlocks the cheap overnight rate for everything else.
Replacing your roof? That's the moment to consider in-roof (integrated) solar, where the panels sit flush and become the roof surface — neater and often cheaper when you're re-roofing anyway. If the roof is staying put, ordinary on-roof panels that mount above the existing tiles are the simpler, lower-disruption choice.
Timing a big-ticket item you were going to buy anyway is how the low-carbon home gets built without ever feeling like a grand project.
The bottom line
There's no wrong door. The EV route and the solar route both end up in the same place — a home running on cheap, clean power — and they meet in the middle once you've added the missing pieces. Start with whichever big purchase is coming up next, let it unlock the next step, and build from there. One decision at a time.