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Home > Archive > Alternative Power sources > August 2007 > Re: Programable thermostats use / uselessness in continuous occupancy setting...
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Re: Programable thermostats use / uselessness in continuous occupancy setting...
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| GeoLegacy 2007-08-19, 8:25 pm |
| On Aug 19, 3:11 pm, Paul M. Eldridge <paul.eldri...@ns.sympatico.ca>
wrote:
> On Sat, 18 Aug 2007 15:38:07 -0700, GeoLegacy <geoleg...@hotmail.com>
> wrote:
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> I wouldn't discourage anyone from installing a geoexchange heat pump
> if that's the way they want to go. I'm just not convinced they're the
> only game in town, now that the efficiency of air source units has
> improved so dramatically.
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> My previous home in Toronto had a twenty-plus year old, 2.5 ton CAC
> that consumed something in the order of 4,500-watts (its EER was no
> more than 6 or 7). I replaced it in 1997 with a 13.5 SEER,
> multi-stage unit that uses roughly 2,200-watts. Today, if I were
> faced with that same buying decision, I would likely opt for a 18 SEER
> system, in which case, my electrical demand would fall to less than
> 1,700-watts, or about one-third my baseline (as mentioned, the SEER
> rating of the ductless heat pump I'm putting in my current home is
> 21).
>
> As you approach SEER 20, the law of diminishing returns takes firm
> hold and any additional savings are likely to be achieved only at
> extraordinarily high cost. If I currently pay $2,000.00 a year to air
> condition my home with a SEER 10 CAC and replace it with a SEER 20
> model, my annual savings are $1,000.00. Not bad. If we could bump
> that up to SEER 25, say, (again, I'm not so sure even geoexchange
> systems can attain such levels), I would save an additional 10 per
> cent or $200.00. Could I recover the higher initial cost of this more
> efficient system in what most consumers would consider a reasonable
> timeframe (e.g., 5 to 7 years)? Most likely, not.
>
> Cheers,
> Paul- Hide quoted text -
>
> - Show quoted text -
If you check the ARI Directory online you'll find that the best
conventional outdoor unit has an EER of just over 15 and the best
Geothermal unit has an EER of 30 as well as a COP of 5. Investment >
ROI over time > Salvage value (added value to sale of home).
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| nicksanspam@ece.villanova.edu 2007-08-20, 9:31 am |
| GeoLegacy <geolegacy@hotmail.com> wrote:
>... the best Geothermal unit has an EER of 30 as well as a COP of 5.
EER = 3.41xCOP, no?
Nick
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| William Mcfadden 2007-08-20, 5:27 pm |
| >>... the best Geothermal unit has an EER of 30 as well as a COP of 5.
>
>EER = 3.41xCOP, no?
I believe they use EER for cooling and COP for heating. It's a bit
confusing.
--
Bill McFadden billmc@agora.rdrop.com http://www.rdrop.com/users/billmc
CAUTION: Don't look into laser beam with remaining eye.
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| Nick Pine 2007-08-20, 5:28 pm |
| William Mcfadden <billmc@agora.rdrop.com> wrote:
>
>I believe they use EER for cooling and COP for heating.
But EER IS 3.14xCOP.
Nick
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| William Mcfadden 2007-08-20, 8:25 pm |
| >>>>... the best Geothermal unit has an EER of 30 as well as a COP of 5.
>
>But EER IS [3.41]xCOP.
(typo corrected)
Agreed. However, a heat pump can have a cooling EER of 30 and a heating COP
of 5 without violating this law. I believe that's the case for the unit
described above.
--
Bill McFadden billmc@agora.rdrop.com http://www.rdrop.com/users/billmc
CAUTION: Don't look into laser beam with remaining eye.
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