Hot water tank insulation - standing heat loss.

[pipandgem]

Which is better a hot water cylinder insulated with foam or one insulated with rockwool.
What does a standing heat loss of 1 KWH/ 24 hr mean over the course of a year?
Any help please to these queries.

 

[gas4you]

You won't get better insulation than the factory coated foam, otherwise all cylinders would be bare copper and we would buy rockwool to put around it.

 

[JohnD]

1kWh costs (depends on your tariff but say) 13pence.

If you are (only) losing 1kWh per 24 hours that is 13p a day

13p x 365 = £47.45 a year

 

[pipandgem]

Just as I thought .. one of those pennies makes pounds.
It doesn't sound much but over a year it will add up.
Thank you for your help.