Tank top heat pump water heater heaters are great for cooling-dominated climates, since they pull the heat from the surrounding room.  But in Boontucky-girl's Iowa climate, not so much. In Jelly's neigborhood, definitely (as well as desuperheaters on the AC, etc.)  In heating dominated climates the net efficiency of a tank-top heat pump will always be lower than that of the heating system, no matter how efficiently the water heater pulls the heat from the room.

There are several tanktop heat pump HW heaters that come built that way (not just the GE) as opposed to marrying a retrofit like the AirTap to a Marathon.  I'm not sure if used hot water heaters can be donated (potential contamination & liability issues.) 

See:  http://www.energystar.gov/index.cfm?fuseaction=heat_pump.display_products_html

Desuperheaters on the air conditioning system are even higher efficiency than tank-top heat pumps, since the heat applied to the hot water is essentially free0 it lowers the load/enhances the efficiency of the AC slightly.  You'd still need to run heating elements or other backup to keep the temp up during the winter though, even in TX & LA.

I just bought the ge hybrid water heater :) so far it works very nice only using
420 watts instead of 4500 watts like my old unit.

The Lexington area is still a predominantly heating dominated climate, which means much of the year you're heating the water at the efficiency, fuel, & fuel cost of the heating system, plus the power used by the water heater.

Hopefully your heating system is high efficiency &/or uses lower cost fuel?

I have a 19 seer carrier hp plus my house was designed for solar heat gain from windows. I guess we see how it does in feb

The heating system probably has a COP of ~2.5 at 25F and a COP of ~3.5-4 at 40F, in which case you're still beating standard electric water heaters most of the time even in winter, just not during cold snaps.

But from April <==> October you'll be quite a bit ahead.

I just recently installed the GE heat pump water heater and I'm quite happy with it. I already had a KWH meter connected to the electrical line to the old standard electric water heater and I was using about 10KWH per day and now I'm down to 2KWH per day. What a great product.

Check with the electric company because that's how I got mine and they installed it. It was $1,450 with a $300 rebate from the electric company and the 30% fed rebate which made it a gread deal.

John

Great info, John. Thanks!

Pedernales Electric Coop isn't particularly progressive with respect to conservation or alternative energy sources, nevertheless, I'll check it out.
--David