I live in a 9000 sq foot house... I worked out; In the summer; I spent an extra $4000 to cool my house In the winter, I spend an extra $1500 to heat it. I have RUUD HVAC's. 90% efficiency. 12 years old. 2 x 4 ton, 2 x 2 ton. One of the 4 -tons in the Attic has finally given up so I started looking for ways to impact my cooling bill (mainly). I was unimpressed at not being able to find ANYONE here in ATLANTA to help me? I get a constant 45-50 degrees from the RIver (150 ft away) that I use to water my yard. Surely, an open loop, pump from the river and let soak back through the ground back to the River. I could even use the same pump (with MAS-Control demand system) that I use today to pump the water on demand for my irrigation. My summer cooling bill could be zero Seriously, any places I could start and find someone that knows how to do it and WANTS to do it?
Any thing is possible, but My first question would be about water rights at your property. Would you be allowed to remove water from the river, add some BTUH, and then return the warmer water to the flow? I have Lake Erie for a back yard, but my property rights end at the water line. The State of Ohio owns the water. Getting permission to alter the BTU content of the water given the current regulations about lake usage would be impossible. Your mileage may very. I have used a developed spring here in Ohio, where the property owner had lower water rights for its use. We piped the spring to fill a poly septic tank and then returned it to the small stream the spring created. We installed a loop field in the tank and pumped to a geothermal unit in the home. Last time I saw it it worked very well. Our first try on this project called for using copper for the heat ex-changer/loop field piping. The water ate the copper in a few months, and we had to redo our engineering using plastic tubing. What you want to do is very possible. I doubt that you could use the river water directly. but it could be used with a heat exchanger to protect the HVAC equipment. I have not been to Atlanta in a long while. Mark
Look at members here and also the igshpa web-site. You may have trouble finding someone who wants to use river water depending on the quality, but there are several ways to do it.
River I would not return the water directly to the River in an OpenLoop system. The unit would be about 200ft from the river and the return can just be open to "feed" into the drainage that runs between my house and the neighbors. This is the natural "soak" for all the run-off rain water from the street (often it floods). All the water flows down further into the troughs at the back of our yards where it sits for 1-24 hours before filtering itself through the ground and back to the river. Even with hours of torrential rain, water never flows over the troughs into the River. Water can flow from the streets/houses for a few days after it's rained. To be honest, it's near perfect. The question about Water quality. Best I can say, I've run my River pump for about 10 years where water gets sprayed over 10 zones, (100+ heads) and the control valves / heads never block. The FILTER on the pump is very good grade. The DAM that pumps the water down the River (15 miles upstream) means the water is good and "fresh" but definitely silty (hence the good filter).
I am lucky, the water quality here is very good. I don't get any blockages in my irrigation valves nor even in the sprinkler heads. I have a very good filter since there is plenty of silt in the river but for 10 years, the quality is pretty good. I assume that's what you all meant? As for the open loop. I would never pump water straight back into the river (and I am sure it would not be allowed). Even the rain-runoff has to go through the ground through channel troughs between the woods and the landscaped yard. After a heavy down-poor, it can flood back there but it filters away very quickly through the ground. Between my and my neighbors house, the main drain from the road empties here as well and again, this is filtered through the soil/sand back to the river. It runs right past where my unit would be. I would keep the open loop just emptying into that. The river is still 200 feet away and the water would disperse in an instant.
There is no valid environmental reason to not return open loop water to its source. Heat exchange adds zero pollutants. We routinely use aquifer water to drive open loop systems and many jurisdictions condone, in fact insist that water be returned to the same aquifer. That said, a surface water source is probably best utilized with an intermediate heat exchanger of some kind Earlier, or perhaps in another thread you wrote you have 50*F source water year round, yet you say you live in Georgia. That does not compute. The only folks with 50*F water available year round from mother nature are those living in southern New England, rural Pennsylvania, the upper bits of midwest vowel states, and similar latitudes and accessing open loop well water. Nebraskans and Coloradans are 50 degree club members as well. A north Georgia river (surface water source) may dip into the 40s in midwinter, but most likely is 70+ in summer. Deep ground temps in Georgia run in the low to mid sixties. Before investing in geo to replace 12 tons of air source heat pumps, look at what might be done to reduce the house's load to well below 12 tons. Meanwhile, there is likely little harm in putting a couple 2" pipes in the open trench...cost is inconsequential relative to retrenching
Update GA I live 12 miles down stream from the Dam and the water that's thrown into the River from 200 ft down in the Lake is mighty cold. So, whilst it may not be 50 degrees, I've been in the river in August and it still numbs the toes! Yes, in fact the new quote I am getting is for a 3-ton system as the GEO team I found seem to believe in "bigger is not better"... They are doing a full sizing exercise for me.
It would be amazing to go from 12 tons to 3 in a 9000 sq ft house. Should I assume you are replacing one of 2 or 3 existing systems?
