how green is my shack?

Relax in southern comfort on the east bank of the Mississippi. You're just around the corner from Beale Street and Sun Records. Watch the ducks, throw back a few and tell us what's on your mind.
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JR.
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how green is my shack?

Post by JR. » Thu Aug 22, 2019 10:50 am

I have long pursued energy efficiency for the old fashioned reasons (I'm cheap). Often suffering through cold in winter and hot in summer from limited spending on comfort. That was then.... over the last year I have made two major upgrades... last summer I put a new light colored tin roof on my house replacing the old black asphalt shingles. This year I upgraded to a modern high efficiency 2 ton heat pump.

Over the last few weeks we've had mid 90's daytime high temperatures and multiple heat advisories. Now for the good news, my electric bill reveals that I used 86% of the electricity that I did this same month last summer. This is with 24x7 air conditioning.

The dollar savings from reduced electricity bills would take longer than my life expectancy to break even, but I do have a nice new roof that doesn't leak and a far more comfortable house, while saving the planet. 8-)

JR
Visit https://circularscience.com to hear what properly "cleared" drums sound like.

terkio
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Re: how green is my shack?

Post by terkio » Fri Aug 23, 2019 6:05 am

Interesting for a hot place I know in Australia.
What is the heat sink of the heat pump ?
An outside air exchanger I presume.
Can a heat pump give an efficient air conditioning using water from a nearby creek ? At the cost of pumping water, though.

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JR.
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Re: how green is my shack?

Post by JR. » Fri Aug 23, 2019 10:14 am

terkio wrote:
Fri Aug 23, 2019 6:05 am
Interesting for a hot place I know in Australia.
What is the heat sink of the heat pump ?
An outside air exchanger I presume.
Yes... outdoor air.
Can a heat pump give an efficient air conditioning using water from a nearby creek ? At the cost of pumping water, though.
That is called ground based heat pump and I have a high enough water table that I could bury a heat sink (pipes) beneath my water table, that would be even more effective, but also much more expensive. :o You can bury ground based heat exchange pipes in dry ground too, but wet ground has even lower thermal resistance.

An old friend of mine has a water sourced heat pump exchanging house heat/cold into a deep water well drilled under his house. Doesn't get more efficient than that.

As it is I will not break even money wise on my 2 ton unit over my lifetime from reduced energy bills, but the modern air exchange heat pumps are more efficient than even a few years ago. Instead of cycling on/off at full tilt, it varies the compressor to regulate the temperature in the evaporator for most efficient transfer to room air.

I expect another significant saving for heating during the coming winter months compared to my previous (cheap) in wall heat pump. My house originally used in-wall resistance heaters.... so pretty large electric bills for winter heat. Several years ago I upgraded to an in-wall heat pump for the main room that was far better than the simple resistance heaters, but lower efficiency than my new modern unit.

JR
Visit https://circularscience.com to hear what properly "cleared" drums sound like.

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