On Thu, 17 Dec 2009 08:28:12 -0800, Lew Hodgett wrote:
I replaced my electric water heater early in 2004. Looking at the
efficiency label on the old water heater and comparing to the new
$300 water heater installed by me, I determined that it would pay
for itself in less than 2 years.

Does your utility offer discount rates for an electric hot water
heater that operates only during off peak hours?

When my dad built our house in 1947, he installed a 100 gallon tank
for 3 people that only operated at night.

We always had hot water heated by low cost electricity.

Yes, that's how ours is... water heater, clothes dryer and baseboard heat
all load-controlled on off-peak. The 30yr old fridge is probably
responsible for a good proportion of our monthly "non off-peak" bill
(along with the TV and the electric stove).

Our water heater's got one of those stickers on it which claims it's
quite high in terms of efficiency - but it's also quite old (albeit
descaled earlier this year) so newer ones probably do better. I
thought about insulating it more, but the outside surface gets barely warm
anyway - plus like with the fridge anything it loses as heat is doing
useful work for more than half the year. Maybe there is a case
for putting it on a timer just during the summer months; we usually
end up using all the hot in an evening, and there's probably no point
having it maintaining water heat all night long...

cheers

Jules