Overnight: the cheap rate
Roughly seven hours. Storage heaters charge here, before you know what tomorrow will need.
Storage heater running costs
Why storage heaters cost what they cost, and why it’s rarely simple
Most people asking about storage heater running costs are really asking about Economy 7. Here’s how that tariff actually works, and where it stops adding up.
- Economy 7 tariff
- Fixed overnight charge
- Smart meter friction
- Daytime top-up rate
The mechanic, explained
Economy 7 gives you cheap electricity at night, and a higher rate during the day
Economy 7 splits your electricity price into two rates: a cheap rate for roughly seven hours overnight, and a standard, often higher, rate for the rest of the day. Storage heaters are built around this. They charge up on the cheap overnight electricity, then release that stored heat through the following day.
The tariff isn’t a discount on your heating. It’s a different pricing structure that only pays off if your usage pattern actually matches it.
Daytime: the standard rate
The other seventeen hours, at a standard rate that’s often higher. Anything you top up with costs this.
Where it stops adding up
The heater doesn’t know what your day actually looks like
A storage heater charges the same amount overnight whether tomorrow is freezing or mild, whether you’re home all day or out at work, and whether you need heat in that room at all.
Charge too little
You’re cold by evening, and reaching for a plug-in heater on the expensive daytime rate.
Charge too much
You stay warm, but you’re paying to heat rooms you don’t use.
Neither is something a newer storage heater fixes. It’s how the tariff and the technology work together.
A real, current problem
Why storage heaters and smart meters don’t always get along
Economy 7 was designed around older meters with a simple day and night switch. Smart meters and modern time-of-use tariffs don’t always map cleanly onto that split, and some households find their storage heaters’ charge cycle stops lining up with when the cheap rate actually applies once a smart meter is fitted.
It’s one of the more common reasons people start looking at alternatives: not because the storage heater broke, but because the tariff it depends on no longer behaves the way it used to.
The alternative
radTherm radiators don’t need a special tariff to make sense
Because radTherm radiators heat on demand rather than storing heat overnight, they work on a standard electricity tariff. There’s no cheap-rate window to plan around, and no risk of a smart meter changing how your heating tariff behaves.
You can keep Economy 7 if you want to, but you’re not dependent on it. That’s a structural difference from a storage heater, not a small one.
Common questions
Storage heater running costs: what people ask us
The questions we’re asked most often by people trying to understand why storage heaters cost what they do.
Why are storage heaters so expensive to run?
Usually it isn’t the heater itself. It’s the mismatch between a fixed overnight charge and a day that never goes exactly to plan. You pay for a set amount of stored heat whether you need that much or not, or run out and top up on the more expensive daytime rate. That unpredictability drives the cost more than the price of electricity does.
What is Economy 7 and how does it work?
Economy 7 is an electricity tariff with a cheap rate for about seven hours overnight and a standard rate for the rest of the day. Storage heaters charge during the cheap window and release that heat afterwards. It only saves you money if your heating needs match that overnight pattern.
Do storage heaters work properly with smart meters?
Not always smoothly. Economy 7 was built around older meters, and some smart meter installations don’t line up cleanly with a storage heater’s charge cycle. It’s a genuine and fairly common issue: not a fault with your heater, but a mismatch between older tariffs and newer metering.
How much does it cost to run a night storage heater?
It depends heavily on how well each night’s charge matches the next day’s use, which is why storage heater running costs are so unpredictable. There’s no reliable single figure, and that’s part of why people look at alternatives that don’t depend on guessing a day in advance.
Do radTherm electric radiators need Economy 7 to be worth it?
No. radTherm radiators work on a standard tariff, so there’s no cheap-rate window to plan your day around. You can stay on Economy 7 if you already have it, but switching doesn’t require it the way a storage heater does.
What does it cost to replace storage heaters with electric radiators?
It depends on how many rooms and what size radiators your home needs, so we don’t quote a figure without seeing it. Every quote from our free survey is fixed and given in person, with no obligation to go ahead.
Stop guessing a day in advance
Get the brochure, or book a free survey
Neil can look at your actual usage and tariff and tell you honestly whether switching would help, with no pressure and no obligation.