MEMPHIS builds a house

[MEMPHIS91]

Originally Posted by stevehull

I did not insulate my sub-slab PVC ducts and my ground temp in Oklahoma is about 60 F. You are a few degrees warmer. I did look into PVC duct insulation and the cost was way too expensive. I did not insulate my slab. Absolutely necessary up in the cold north. Ok so I would need to plan on a small room in the centerish of the house because the unit is not to like pushing the air 50 feet through a 8" pipe.

Of course you will need amps to run a deep well pump, but you don't need pressure and you can run a GTHP on 10 psi. Then have a separate "booster" surface pump to do 60 psi for home use. Gotcha, that sounds like it makes sense but without a diagram or picture I will need to look it up more lol

The alternative to an open loop (aka "pump and dump") is to put in expensive vertical wells or did like crazy and put in a huge loop field. Lots of time and or $. I have a digging machine capable of digging to 27' in one scoop, so going deep in a loop field would not be that hard. Just another idea.

Solar, to run a pump with a grid tie, is NOT expensive. If fact, it is so cheap that you can't afford not to do it. Your 20 year lifetime kWhr cost will be a fraction of the current retail kWhr cost. I will plan on adding this to the solar system design

But you did confirm, "as efficient as money will allow" . . . . . Maybe I should say as much money as well be helpful, I don't want to pay 40k for a 2% increase in performance.

I would do open loop geothermal, a 10 kW solar system and a SIP home. You are FAR better to do solar PV and efficient heating/cooling now. If you install yourself (not hard) the cost is about $1.1 a watt. Then the 30% tax credit - so the real cost is about $0.75 a watt. I will post a floor plan soon so that recommendations can be made on the how and where for sip/conventional building

This means about $7,500 to put in a 10 kW PV system, let's say $4K for a GTHP (including ducting). That total is under $12K. Pay someone to do this and add another $20K. Typical charges to put in a grid tied PV system are $3+/watt. $7,500 plus an inverter plus racking plus wiring and that is if TVA will pay me for the solar I make, unless I go off grid, in which case batteries will cost more than the house. Don't get me wrong I'm going to have solar, but $7,500 is shy of the real cost.

Start by setting yourself up for savings and then put other important stuff around it - like LED bulbs, SIPS, tight house, ERVs, etc.

Think strategically - not tactically . . . . it is all about saving money down the road.

Lastly, what you pay for electricity is AFTER tax money. Lets assume you are in the 20% IRS bracket (being conservative). To make $100 in take home, you have to make $120. But you pay for all stuff AFTER taxes. That is why money saved is such a boost. I like saving money


Steve

I don't think open loop would save that much money. Those pumps still use lots of power, and they don't give me usable water, and you have to worry about freezing your loop field. Submersible Pump 4" Deep Well 1 HP 220V 33 GPM 207 ft Max Long Life | eBay