Another heat pump water heater
 

Here is another heat pump water heater, made by a German company that makes alot of solar hot water storage tanks, pumps and controls, I saw one in real life at the Midwest Renewable Energy Fair, but it was new enough that they didn't have any printed info yet but there is info on their web site.

Stiebel Eltron | Accelera 300 Heat Pump Water Heater

retail price is supposed to be around $3,500 so the "payback" could be as much as 10 years, talked to a friend of mine who installs solar hot water systems and he said that if all of their claims are true (not always the case) that water heaters like this could be a better deal then the solar hot water systems that he sells.

It just seems to be a more expensive version of the Airtap.

Yes, it costs more then the air tap, but the air tap is a retrofit kit, this is a whole water heater, the air tap has an efficientcy of around 2.2 times greater then a simple heating element at 55F and this Stiebel Eltron is 3.2 time more efficient then a heating element, it also has a better warranty, heats a 80 gallon tank instead of a 50 and is made by a company that normally makes solar hot water equipment.
I'm going to wait 6 months to a year to get something like this, partly to see what else comes out as I think this is going to be the next wave in water heating.

thanks for the link

the other day i was reading about heat pump water heaters because they're listed on the energy star stimulus package tax credit site in the non-solar water heater category. I looked online and couldn't find them anywhere here in the U.S.

But... on this energy star site that describes them, they say "New models due out later in 2009 will utilize super-efficient technology to cut electric water heating costs by more than half! If you have time to plan ahead, consider this exciting new technology for your next water heater purchase."

... so basically I think these things are about to hit mass market (home depot / lowes) later in 2009 in America... which should drive the costs down way below $3500.

Let's keep our fingers crossed... :-)

some more links of this stuff.

Efficient Water Heating

Aers : E-Tech

http://www.energy.wsu.edu/documents/...water_htrs.pdf

http://trevormartin.com/documents/HWG_Spec_WCC12.pdf

http://www.aers.com/aers/system/data...20E%201-08.pdf

http://www.aers.com/aers/system/data...%20%205-08.pdf

http://www1.eere.energy.gov/femp/pdf..._heat_pump.pdf