On Wed, 21 Jan 2009 18:19:33 -0600, "AlaJoe"
wrote:

I have a 50 Gallon electric water heater that is just not getting the
job done. One person can shower as long as he wants but the recovery time is
just too long between users and My wife, My kid and ,myself are trying to
take showers within one hour and it just will not keep up. So I am looking
to either add an additional water heater and split off one bathroom or
increase the size of the one. My question is about energy usage.
I have looked at 30-80 gallon heaters and there does not appear to be
much difference in energy usage. The 30 Gallons heater have an annual energy
estimate of about $405 to $410 and 80 gallon heaters about $440 to $450.
Does this mean if I add a 30 gallon water heater in addition to the 50
gallon I already have to seperate one bathroom I will spend about $820 to
$850 a year to keep 80 gallons of water heated to where I could buy just one
80 gallon and only spend about $450?
Would one 80 gallon allow three people to take back to back showers?
Which set up would work best?

Joe

I think the annual energy cost estimates are based on an estimate of
the average amount of water used by a family of four at some average
fuel cost.

You can find info on estimating cost more accurately he

http://apps1.eere.energy.gov/consume.../mytopic=13010

Having two tanks won't double your cost if your water usage remains
the same. You will still be heating the same amount of water. Two
tanks will cost more, because the standby loss (energy required to
keep the water at temp when it is not being used) will be about
double, but standby loss is around 15-20% of total energy usage, so
your total cost won't double. Standby loss for electric heaters is
less than for gas because there's no flue running up the middle.

But before you do something drastic, look at, or have a plumber look
at, the simple stuff. Is the tank full of sediment? Is one element
burned out? (a common cause of low recovery rate) Is the dip tube OK?
Do you have low flow shower heads?

50 gallons is usually OK for 3 people.

HTH,

Paul F.