What If Home Energy

Know your energy costs.

A UK household energy app that answers one question: what would my bills be if I changed something? Model a change, compare it against what you pay now, and see the difference in pounds before you commit to anything.

What you can model

Adding solarPanel size, self-consumption, and what you'd actually export.
Adding a batteryIncluding time-shifting into an off-peak window.
Switching tariffYour own rates, with exit fees and switch dates accounted for.
Riding the price capWhat the Ofgem cap would cost you now, and next quarter.
A heat pumpHeat demand from your actual home, with an efficiency you set, or a typical one.
An electric vehicleHome and public charging, at the right rate for each.
Better insulationWhat a filled cavity or a thicker loft would take off your heating.

What If Plus

An optional one-off purchase — not a subscription — for households on smarter tariffs. It adds tariffs with several cheap windows a day, a battery modelled hour by hour through your day, charts of your home on an average, a winter and a summer day, and reminders when your fix ends or Ofgem announces the next cap. Everything above stays free.

Your data stays on your phone

There is no account, no sign-in, and no analytics. Everything you enter is stored on your device, and we have no way to read it. One optional feature sends a partial postcode to look up your energy region — never your full address, and you can skip it. Read the full privacy policy.

Available now

Free on the App Store for iPhone, in the United Kingdom, with an optional What If Plus upgrade. Download What If Home Energy.

More from us

Four apps, one idea: your own numbers, worked out on your own device, with nothing to sign into and no account to make.