Need help choosing a new heating system!

matelodave

Hot water from a gas boiler (on mains gas) will cost you around 2.5-3p/kwh, whereas using an electric shower on an e7 tariff during the day could cost you 15-20p/kwh depending on how much your peak rate is - it's cheaper if you shower during the middle of the night as you can use the off-peak rate.(you could also use the hot water from a tank heated on off peak rates and get the benefit with a conventional shower, rather than electric)

A 10kwh electric shower will use 1.6kwh of electricity in ten minutes - on gas = just under 5p, on peak rate leccy it could be between 25p and 32p. Check your tariff to see how much it's costing you

Gerry1

Do you prefer an instantaneous electric shower at 15.74pp kWh, an E7 immersion heater shower at 7.96pp kWh, or a mains gas shower at perhaps 2.4p/kWh?

hozza94

Jules2054 said:

Just a thought, but at the moment I've got a separate fused electric shower fitted....would this work better coming off the boiler,  in terms of running costs? Or not? 
I suppose it would, as if the boiler is on to heat the water, then there's no point in using electricity to use the shower!!!! Is that right? Lol! Brains not working today! Lol! 😊

Pretty spot on. If the water from the boiler is hot enough to have a shower, then there is no point of having an electric shower. 
I have an open-vent immersion cylinder and it retains the heat so well that water is still very hot just before e7 time. 
So it's all about cost here, is your immersion a storage one? 

Jules2054

matelodave said:

Hot water from a gas boiler (on mains gas) will cost you around 2.5-3p/kwh, whereas using an electric shower on an e7 tariff during the day could cost you 15-20p/kwh depending on how much your peak rate is - it's cheaper if you shower during the middle of the night as you can use the off-peak rate.(you could also use the hot water from a tank heated on off peak rates and get the benefit with a conventional shower, rather than electric)

A 10kwh electric shower will use 1.6kwh of electricity in ten minutes - on gas = just under 5p, on peak rate leccy it could be between 25p and 32p. Check your tariff to see how much it's costing you

The tariff I'm on atm is 15.74ppkwh peak rate and 7.96ppkwh off peak. 

Jules2054

Gerry1 said:

Do you prefer an instantaneous electric shower at 15.74pp kWh, an E7 immersion heater shower at 7.96pp kWh, or a mains gas shower at perhaps 2.4p/kWh?

Obviously, I'd prefer the mains gas, but the E7 immersion heater shower at the lower cost is doable. So what type/brand is best to work with the E7 immersion heater? Or should i just wait to sort it when the new system is in situ? 

Robin9

Jules - don't forget that your electric will still cost - usage, standing charges - in addition to the LPG costs.   What have you included in your budget ?

Jules2054

hozza94 said:

Jules2054 said:

Just a thought, but at the moment I've got a separate fused electric shower fitted....would this work better coming off the boiler,  in terms of running costs? Or not? 
I suppose it would, as if the boiler is on to heat the water, then there's no point in using electricity to use the shower!!!! Is that right? Lol! Brains not working today! Lol! 😊

Pretty spot on. If the water from the boiler is hot enough to have a shower, then there is no point of having an electric shower. 
I have an open-vent immersion cylinder and it retains the heat so well that water is still very hot just before e7 time. 
So it's all about cost here, is your immersion a storage one? 

My immersion heater is a 2 element one, with 0ne connecting to the booster and one to the E7, however, I have rewired the E7 to the larger tank, so I get more hot water on E7 overnight! 
It's got to be over 32yrs old, so could do with replacing, maybe? 

Gerry1

Just check the thermostat on the lower immersion heater, that's probably the culprit.  Start by turning it fully up to see whether it works overnight.  If the element is faulty, just get it replaced. 

Gravity should run your shower, but if you have a pumped shower (i.e. no instantaneous heating) it won't be a special E7 one, it won't care what the electricity supply is.

Jules2054

Robin9 said:

Jules - don't forget that your electric will still cost - usage, standing charges - in addition to the LPG costs.   What have you included in your budget ?

Yes, I'm aware of that, but if the LPG works out cheaper or the same as E7 overnight, for heating the water, then it's better to use the LPG? 
The LPG standing charges work out at about £6.67per month, whereas the leccy works out at £6.16 per month, so not much in it! 

Gerry1

Jules2054 said:

Robin9 said:

Jules - don't forget that your electric will still cost - usage, standing charges - in addition to the LPG costs.   What have you included in your budget ?

The LPG standing charges work out at about £6.67per month, whereas the leccy works out at £6.16 per month, so not much in it! 

Unless you switch to gas lighting and a solar powered laptop you'll still need to pay the electricity standing charges !