[Greenbuilding] multi-splits

[Paul Eldridge]

Hi Sacie,

We have a forty-four year old, 2,500 sq. ft. Cape Cod that we've 
upgraded over the years, and virtually all of our space heating 
requirements are met by two high efficiency, inverter-drive ductless 
heat pumps [in the event of an extended power cut, we operate our 
oil-fired boiler on generator power].  Both heat pumps are monitored and 
so far this heating season they've consumed a combined total of 120.5 
kWh, or $16.63 at 13.8-cents per kWh.

October's mean temperature was 10.5C, and nine days into November, the 
current month stands at 6.3C.  We have little passive solar gain to 
speak of, so we're pretty much dependent upon this one heat source to 
carry the full load.

BTW, in another thread there had been suggestion that our new heat pump 
water heater would consume **TWICE** as much electricity as the 
conventional electric tank it replaced.  Well, our HPWH has been 
operational for twenty-five days now, and during this time has consumed 
42.23 kWh, or an average of 1.69 kWh a day.  However, it has offset 
approximately 80 hours of our dehumidifier's runtime, which has in turn 
eliminated about 40 kWh of electrical demand (the outdoor relative 
humidity as I type this is 100 per cent).  In effect, our Nyle is 
supplying us with "free" hot water.  It does steal heat from a 
conditioned space, but the heat that is sacrificed for DHW purposes is 
supplied by our ductless heat pumps at roughly one-third the cost of 
electric resistance or oil.

Cheers,
Paul


> Message: 1
> Date: Wed, 7 Nov 2012 21:39:55 -0600
> From: Sacie Lambertson <sacie.lambertson at gmail.com>
> To: Greenbuilding <Greenbuilding at lists.bioenergylists.org>
> Subject: [Greenbuilding] multi-splits
> Message-ID:
> 	<CAM6L0t4JYtB6CO0cBK=_w-xzAECcEEsLnm=dk3ROit+ry6_uQA at mail.gmail.com>
> Content-Type: text/plain; charset="iso-8859-1"
>
> Interesting series about changing out oil broiler for a minisplit here:
>
> http://www.greenbuildingadvisor.com/blogs/dept/guest-blogs/installing-ductless-minisplit-system
>
> http://www.greenbuildingadvisor.com/blogs/dept/guest-blogs/living-point-source-heat?utm_source=email&utm_medium=eletter&utm_content=20121107-home-energy&utm_campaign=green-building-advisor-eletter
>
> The cost of electricity on Martha's Vineyard where Marc is located is 6.8
> cents/kWh.  Would be nice; here in NE Kansas, our base cost is 13 cents/kWh.
> Makes a big difference were one to consider installing a minisplit.
>
> Sacie