Dan wrote:
Recently bought a house in the Seattle area, built about 1980. At the time
the house was built, there was no gas in the area. The house has a heat
pump, which is nearing the end of its life. Natural gas is now available in
the area. I'm wondering if I should go with another heat pump, or natural
gas. Since about 80% of the electricity here is hydro, it's relatively
cheap, about $.08/KWH. I don't know what the price of the gas is per cu',
but I could find out. Is there a way I could get a rough estimate of how
much natural gas I would consume to heat the house, based on the electricity
used for this purpose? There are a lot of confounding factors, the relative
efficiency of the 2 units (old heat pump vs new nat'l gas furnace), the fact
that I also use electric to heat water, etc. (can probably find some rough
figure for factoring this out) the relative costs of each type of
replacement (I would add AC to the gas furnace, so I'm guessing the gas/AC
unit would cost more to buy initially than the heat pump, especially if I
have to shell out for the gas line to be run). Coming from the midwest,
electric heat was always seen as significatly more costly than natural gas,
but I don't know if this is still the case just in general, and particularly
if it would be true given this region's relatively low electric rates. Any
helpful comments appreciated.

TIA,

Dan



What altitude are you at? Microclimates in "the Seattle area" vary
widely and wildly.
Go up 3,000 feet and you have a whole different set of heat needs than
if you are on
Puget Sound.

What is the back up heat source for your heat pump? Resistance electric?
What is your power ompany, Seattle City Power and Light, or Tacoma
Power, with preference access to BPA hydro, or a private utility like
Avista with no current access to BPA hydro?

What will the effect be two years from now of the 9th Circuit ruling
last August re
BPA preference power and the legislation pending in the US Senate to
overturn
that ruling, and let the investor owned uilities have some of the BPA hydro?

What will the gas co charge you for an install from the mains in the
street into
your basement?

Are you going to convert from electric to gas stove? (I would, I hate
electric stoves).
Willyou get a discount on the gas pipe install if you switch the stove
and the domestic
ot water heater while you add gas heat?

What do manual D (?), manual M (?) manual J (?) calculations tell you about
the heating / cooling needs for your house. How well insulated is it?
What kind of windows do you have?

You need answers to all these quesions before you can make a knowledgable
"guesstimate" on the efficacy of electric heat pump vs. gas.

Gut rule of thumb here in Portland, Oregon, where we are generally
without the benefit
of heap BPA hydro is that gas in a 90% or 95% efficient furnace is
cheaper, by a long margin, than an electric ea pump with supplmental
resistance heat. And furnaces tend to have a much longer
operating life than a heat pump. Espeially a heat pump who's compressor
is used for AC as well as heat

And why do you need AC in the Seattle area?

How old is that heat pump you are considering replacing?