Hybrid Electric Water Heater

So, if this thing uses ambient heat it makes the room it's in cooler. For half the year it's substituting room heating costs for water heating costs.

First, you must determine whether or not the water heater is in a "conditioned space" which is defined as a room of the house that supplies return air to the HVAC system. Typically water heaters are in "unconditioned spaces" such as garages, basements, and attics, which do not provide an air supply to the HVAC system. Therefore, any heat removed from these spaces by the hybrid water heater would not need to be replaced by the furnace. If the hybrid water heater is in a conditioned space inside the home such as in a utility room, it will lessen the load on the AC system during cooling months and increase the load on the furnace during heating months. If the number of cooling months equals the number of heating months, these effects will roughly offset, and the user will still experience all the energy saving benefits of the hybrid water heater. If cooling months exceed heating months, this will be an additional benefit to home energy savings beyond the savings of the hybrid water heater itself.

True; it's a heat pump. There's another technology which is now in production, which prewarms water going into the heater by passively extracting it from wastewater. That would be a more efficient system.
www.inventure.ca/Drainergy.html

Hey Brian, thanks for the 'drainergy' link, looks like a good product and I'm sure it's a lot less than $1600. Keith, thank you for a great explanation of operational cost for the hybrid heat pump. Check out the 200% efficient Acadia at www.gotohallowell.com

People who use propane to make hot water should seriously consider taking advantage of the 30% tax credit for this Rheem hybrid heater. My old water heater consumed about 307 gallons of propane a year ("energyguide" yellow stickers). This was costing me about $900 a year for just hot water. A new conventional propane ge "energy saver" water heater, for example, would still use about 260 gallons ("energy saver" standard water heaters don't qualify for the 30% tax credit). A tankless water heater would still consume about 200 gallon a year of propane, but entail significant installation costs. Switching to this heat pump water heater saves me about $700 a year in energy costs (propane costs minus electric costs).

That is, while it cost me $3000 for the water heater, installation and bringing high voltage electricity to my furnace room, for a fair analysis, this big investment figure needs to be reduced by (a) 30% ($900) tax credit for the water heater and its entire installation costs and (b) the $800 I would have to spend to replace my old water heater. Thus, my net after tax, additional investment came out to (3000 - 900 -800) to $1300 -- which equals two years energy savings.

All of the work was performed through my local Home Depot (my local Lowe's didn't want to touch running an electric line from the fuse box to the furnace room). I've got a 12 year extended protection plan. Using the heat pump alone mode, we all had very hot showers in an hour. When the heat pump compressor kicks it, it makes a quiet buzz that does not disturb me. In fact, if the a/c fan is running, I can't even hear the Rheem compressor, when it kicks in. It does just fine in the furnace room of a three story townhouse and its compressor doesn't kick in that often.

Without the tax credit, next year you might want to also give consideration to a standard electric water heater. But, if you can, utilize that credit this year. I've also learned that putting in an electric line for a water heater isn't that difficult or expensive. While I expect the cost of the heater to decline in the coming year, I would take advantage of the tax credits this year.

For me, there is the additional benefit of getting away from depending on oil and the propane produced by refining oil. Since there are so many alternative ways to generate electricity, as compared to making transportation type fuel, I don't mind using a little bit more electricity (2200Kwz a year) from the power plant. We are living in interesting times and I'm waiting for the day that I can replace my furnace which also consumes propane (but more efficiently).

One last point: I reduce my use of carbon fuels by about 300 gallons a year for an investment of $3,000. Getting about the same reduction by buying an electric car requires an investment of over $30,000. If you can, please spread the word.