Immersion heater - what tariff is best

Hi, I moved into my apartment last month (bulb was already the supplier) and I have a smart meter and I’m on a 1 rate tariff.

I have an immersion heater that causes a huge spike in my daily costs! I’m in a 1 bed apartment, living alone with hardly anything on in the day and still spending £3/£4 a day. I’ve noticed this is mostly due to when I have my immersion heater on.

Has anyone found it’s better to be switched to a 2 rate tariff/day and night with this kind of hot water system?

Getting to the point where I might just have cold showers haha

Hi @laurenj :wave: Welcome to Community,

Is your immersion heater on a timer? At what time of day does it normally come on to heat your water?

Moving onto a 2 rate tariff is something we can look into but I cannot make any guarantees at the moment.

– KT :bulb:

Thanks for your reply, it’s a timer I set myself, however I would rather have a Tarif where I can put it on the cheaper rate.

Currently I have it on at 6pm for an hour (which isn’t long enough) however it’s so expensive to have on longer

I would rather have it on overnight

Have you considered upgrading the shower to an electric shower that heats its own water? (assuming it’s not already)

That way, you might not need to use the immersion at all, as if your need for hot water is principally for the shower, it would be more efficient to just heat the water actually used than the whole hot water cylinder.

Immersion heaters are usually 3kW, so you’d expect it to be around 75p/hour to run (at 25p/kWh). Some are 6kW, which would obviously cost double that - although you’d expect to run them for half as long to achieve the same amount of hot water (ie overall, there should be no practical difference in running cost).

Electric showers tend to be in the range 7kW-11kW, so cost up to ~46p for a 10 minute shower (at 25p/kWh).

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Hey @laurenj

It may be worth you taking a look at our tariff information here and see what you would be charged on a 2 rate.

You would benefit from using or charging your heater if you did so in your cheaper hours.

The off-peak hours for Economy 7 meters usually fall somewhere between 10pm and 8am. The actual hours vary across the country, and they depend on the type of meter you have too. This would be the best time to use your appliances.

–Carl :bulb:

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I definitely think I would save by having 2 rates.

I have a smart meter, is it possible to have this kind of Tariff?

Hi @laurenj

I can have a chat with our metering team today to look at moving you over to two rate, I will send an email over today with an update.

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