[Greenbuilding] Ductless Heat Pump Performance - November 2011

Paul Eldridge paul.eldridge at ns.sympatico.ca
Sat Dec 3 08:44:19 PST 2011

Hi Richard,

Both are Sanyo 12KHS71s which are inverter models that continue to 
supply a good amount of heat, economically, down to -22°C (see: 

You can view our main floor indoor air handler at: 

Fuel oil locally currently sells for $1.137 a litre and at 82% AFUE that 
puts the present cost of oil heat at 13-cents per kWh(e).  By 
comparison, our ductless units are heating our home at effectively 
4-cents, or less than one-third this cost.

I should note that our operating costs will creep closer to 5 or 6-cents 
as the heating season progresses and air temperatures continue to fall, 
but then they'll drift back down again as we move into the latter part 
of spring (our heating season along the coast basically stretches from 
October 1st through May 31st).  Of course anyone who heats with oil is 
painfully aware that oil prices also fluctuate in sympathy with the 
weather and in some parts of Canada folks are already paying as much as 
a $1.41 a litre.  Thus, a standard tank fill can set you back a cool 
$1,300.00 !  Nein danke.


>These are great numbers. I've been doing some homework on these systems for
>a while. Does your heat pump incorporate "inverter" technology?
>On Fri, Dec 2, 2011 at 9:10 PM, Paul Eldridge<paul.eldridge at ns.sympatico.ca  <http://lists.bioenergylists.org/mailman/listinfo/greenbuilding_lists.bioenergylists.org>
>>/  wrote:
>>/  We have a forty-three year old, 2,500 sq. ft. Cape Cod and in past years
/>>/  when we heated with oil exclusively, our fuel oil consumption averaged
/>>/  about 2,000 litres a year (space heating and domestic hot water).  Today,
/>>/  virtually all of our space heating needs are satisfied by two ductless heat
/>>/  pumps and our DHW is heated electrically.  Each of these loads is
/>>/  individually metered and a breakout of our consumption for November can be
/>>/  viewed at:
/>>/  http://i362.photobucket.com/albums/oo69/HereinHalifax/HP-Nov2011.jpg  <http://i362.photobucket.com/**albums/oo69/HereinHalifax/HP-**Nov2011.jpg%3Chttp://i362.photobucket.com/albums/oo69/HereinHalifax/HP-Nov2011.jpg>
/>>/  A summary of our heat pump savings for the months of October and November
/>>/  can be viewed at:
/>>/  http://i362.photobucket.com/albums/oo69/HereinHalifax/ONHPR.jpg  <http://i362.photobucket.com/**albums/oo69/HereinHalifax/**ONHPR.jpg%3Chttp://i362.photobucket.com/albums/oo69/HereinHalifax/ONHPR.jpg>
/>>/  For the first sixty-one days of this heating season (i.e., October 1st
/>>/  through November 30th), our heat pumps have consumed a combined total of
/>>/  498.6 kWh or an average of 8.2 kWh per day.  This is the energy equivalent
/>>/  of 0.93 litres or 0.25 US gallons of fuel oil a day at 82% AFUE and an
/>>/  indoor set temperature of 20°C.
/>>/  Our goal this year is to get our total household consumption below the
/>>/  10,000 kWh mark which, if we should succeed, would put us in the range of
/>>/  43 kWh/m2.  In an effort to further minimize our ecological impact, 100 per
/>>/  cent of the electricity that we use is wind or low-impact hydro sourced
/>>/  through Bullfrog Power (http://www.bullfrogpower.com/**).
/>>/  Cheers,
/>>/  Paul

More information about the Greenbuilding mailing list