Electric only home

matelodave

coffeehound said:

Fitting an instantaneous electric shower would be a major help.  If used during the off-peak period, it will use cheaper rate electricity.

You'd have to shower between midnight and 7am but TBH that's going to be a lot better than flushing a whole batt full of water away. A bath hold between 60-80 litres (more if its a big one or you fill it right up). A hot water tank can be anywhere between 100-300 litres - hopefully with a big house it's towards the larger capacity.

The only way with electric heating is with E7, storage heaters and a hot water tank you can heat overnight and no baths.Anything else will cost a significant amount of money (including the option of a heatpump) Only short showers either from the hot water tank or with an instant electric unit  during off peak hours. Ideally the showers should be eco or low flow to avoid using silly amounts of water.  It's easy to dump the equivalent of a bath full of water down the drain with a shower unless it's used intelligently, no longer than five minutes at a time. (ten minutes at 10lpm = 100litres whereas 5 mins at 6lpm is only 30 litres)

coffeehound

I suppose one benefit of electric showers is that they are by definition low-flow!

danrv

matelodave said:
Only short showers either from the hot water tank or with an instant electric unit  during off peak hours. 

I have an instant electric shower unit but don’t always manage to limit usage to off peak hours.
The bath is from an immersion tank heated during low rate and ideally, the shower would use this water too. 
The tank isn’t far from the bathroom but is on the same level so it would need a pump if changing. 
Cheaper running this way though and no time constraints.
Would suit a large family.

Hasbeen

madeye25 said:

I am due to purchase a detached 5 bed home that does not have gas supply.
I would reconsider purchase.

I have no intention of exploring the option of getting gas connected.
Why not?

madeye25

Alot of comments which I really appreciate. 
Just to be clear, I wouldn't say money isn't an object but I would far prefer the easy life rather than the cheap life.

There is sufficient advice here for me to have a look at some different type of systems and tariffs. 

Is there some sort of database somewhere that records how much energy is used heating a 300L immersion tank (or other sizes) each night, and how much emergy an instant electric shower unit uses for example?

matelodave

https://www.sust-it.net/immersion-heater-energy-calculator.php this'll tell you how much it cost to heat your tank (put in your own tariff rate)
Its not hard to work out how much an electric shower uses - 10kw x 10 minutes = 1.66kwh x 15p/kwh = about 25p (again put in your own cost per kwh)

madeye25

matelodave said:

https://www.sust-it.net/immersion-heater-energy-calculator.php this'll tell you how much it cost to heat your tank (put in your own tariff rate)
Its not hard to work out how much an electric shower uses - 10kw x 10 minutes = 1.66kwh x 15p/kwh = about 25p (again put in your own cost per kwh)

Perfect, thank you!

coffeehound

Just to be clear, madeye25, I was suggesting the electric shower as an addition to your current set-up.  They are good as a 'standby' option as the hot water doesn't run out and they are independent of the main hot water system, so still work when the immersion heater fails.  However they are not the strongest shower experience in winter due to mains water being colder.  Therefore a 10 or 10.5 kW one per the example is preferable if you want a stronger shower flow.

Your idea for a second hot tank might make sense if one of your bathrooms is a long distance from the existing hot tank.  The shower and taps then run hot quicker and waste less.  Plus as you say it gives the option to switch off while not in use.  Be aware of Legionella growth if not regularly used though.

danrv

MWT said:.

The key factor though in this case is exactly what type of electric heating the OP currently has...

Yes, still not sure. Any info from the OP would be useful. As mentioned, heating a five bed house on electric far outweighs hot water.

madeye25

Apologies - the home is heated by electric heaters/radiators.

I have been doing some research and infrared may look like an option with potential. 

I could trial it one of the rooms perhaps.