Around two million UK homes heat primarily with electric storage heaters. They’re most common in all-electric properties — flats, maisonettes, and older houses built without gas connections — and in homes where Economy 7 tariffs made overnight electricity cheap enough to make the maths work. If that describes your home, you’ve probably noticed that it doesn’t work quite as well as it used to. Rising electricity prices have squeezed the Economy 7 advantage, and the technology itself is from another era.
The question is whether heat pumps are a genuine upgrade or just an expensive green initiative that doesn’t actually make sense for your situation. Here’s the honest picture.
What Storage Heaters Actually Cost to Run
Old brick storage heaters are genuinely expensive to operate. A typical three-bedroom home running on old brick storage units on Economy 7 pays roughly £1,200 a year on the off-peak rate alone, with another £400 or so in peak-rate top-up heating when the stored heat runs out mid-afternoon. That’s around £1,600 a year before you add hot water.
Modern high heat retention storage heaters are noticeably better. These units from manufacturers like Elnur, Dimplex, and Creda use advanced core materials that hold heat more effectively and release it more gradually, and they have sensors that adjust charging based on weather forecasts and your usage patterns. On Economy 7, a three-bedroom home with modern high retention heaters typically costs around £1,000 to £1,150 a year. That’s a real saving, and the capital cost is relatively low compared to a heat pump.
So if you’re on old brick units, upgrading to modern storage heaters is a reasonable first step with a payback period that’s hard to argue with.
Why Heat Pumps Are Fundamentally Different
Heat pumps don’t generate heat from electricity the way storage heaters do. They move heat from outside air (or the ground) into your home, using electricity to run a compressor. The result is a coefficient of performance of three to four, meaning every unit of electricity you put in returns three to four units of heating energy. Storage heaters deliver one unit of heat for every unit of electricity — they’re simply resistive elements converting electricity directly to warmth.
That’s the entire reason heat pumps cost so much less to run. It’s not a marginal improvement; it’s a fundamentally different physics.
An air-to-air heat pump, which works like a reverse air conditioning unit and doesn’t need wet radiators, typically costs £600 to £800 a year to heat a three-bedroom home on a standard single-rate tariff. An air source heat pump with a wet radiator or underfloor heating system, running on a smart tariff like Cosy Octopus that gives cheaper rates during overnight and off-peak hours, brings that down to £400 to £600 a year. The Energy Saving Trust estimates that switching from old electric storage heaters to an air source heat pump saves the typical three-bedroom home up to £1,200 a year. That’s not small.
The Grant Situation in 2026
The Boiler Upgrade Scheme provides a £7,500 grant toward the installation of an air source heat pump. Installed costs for a three-bedroom semi-detached house typically run from £8,000 to £14,000 before the grant, which puts the net cost at £500 to £6,500 depending on your property and what work is involved. Ground source heat pumps attract a higher grant of £7,500 as well, though the installation cost is considerably higher.
To claim BUS, your property needs to have at least a moderate level of insulation (you’ll be asked to confirm there’s no outstanding recommendation for cavity wall or loft insulation on your Energy Performance Certificate), and the installer must be MCS-accredited. The grant is applied directly through the installer — you pay the net amount rather than claiming money back.
The ECO4 scheme is worth checking if your household is on certain benefits or has a low EPC rating. For storage heater households on a low income, there may be grant options covering the full cost of switching, not just a contribution.
Who Should Actually Consider Switching
Heat pumps make most sense for houses with outdoor space where an air source unit can be positioned. They work best in well-insulated properties, though they’re more tolerant of modest insulation than the early marketing suggested. Most existing radiators can run adequately with a heat pump, though you may need to upsize a few to compensate for the lower flow temperature heat pumps operate at (typically 35 to 45 degrees Celsius rather than the 65 to 70 degrees a storage heater can achieve at the element).
Flats are more complicated. An air-to-air heat pump doesn’t require wet radiators and is feasible for many flats, but you need external wall access or a suitable outdoor space for the unit. In leasehold properties, you’ll also need freeholder permission for external installations. It’s not impossible, but it adds steps.
If you rent your home, the upgrade decision isn’t yours to make — though it’s worth knowing that landlords face minimum EPC standards that may push them toward heat pump installations over the next few years, especially in properties currently rated below a D.
Practical Next Steps
Get an MCS-accredited installer to assess your property before making any decisions. They’ll look at your insulation levels, existing radiator sizing, and available outdoor space, and give you a realistic cost and savings estimate specific to your home rather than the industry averages that guides like this one have to rely on.
It’s also worth comparing your current Economy 7 tariff against alternatives. If you switch to a heat pump, Economy 7 pricing becomes less relevant — heat pumps work well with demand-flexible tariffs like Cosy Octopus or Octopus Agile that give lower rates during overnight and shoulder periods rather than the fixed split that Economy 7 offers.
Modern high heat retention storage heaters remain a reasonable option if your property makes heat pump installation difficult. They’re not exciting, but the cost saving over old brick units is real, and the disruption is minimal. The heat pump payback calculation works better for houses than for flats, and for properties that already have decent insulation.