Municipal geothermal loops

So hypothetically it can be done and from what I have read here is done is some localities. Maybe I am not connecting the dots, if I take the incoming municipal supply and dump it back through a drain are people suggesting there could be some contamination? I am not sure if the municipality is recycling the grey/storm water , I am thinking they just discharge it, as I said water is not an issue in these parts, it is abundant. Look forward to you responses...great forum!

 

We are talking about returning municipal potable water to the same potable water main after borrowing some btu's. Dumping a geo volume of water into a waste drain is just plain wastefull of a municipal supplied resource. Potable water is finite and should be handled responsibly.
Eric

 

Well, as he said in his area water is not a scarce resource. In some areas of course it's extremely scarce. But no BobD, the contamination we're talking about is just regarding whether it is still suitable for drinking after going through the heat exchanger, not if it's going to be toxic to the water table or after waste treatment. Sadly, I suspect we would have much more to worry about from neighbors improperly disposing of their pharmaceuticals and other chemicals into the badly sealed landfills or the sewer than from a professionally-installed main-exchanged GHP.

 

I want to reply to this directly. You are alluding to recapturing "sewage waste heat" here? How does its usefulness change as climate gets warmer?

 

We try really hard to not " Get into politics" on this forum, it just clouds the really good GSHP content and wastes bandwidth.
Eric

 

Got a heat loss of approx. 30000 and an average of -7 temp during the heating months. How much input \ discharge am I looking at per day, may mot even have the input capacity which will make all a mute point.

 

I think there are fairly adamant codes against any water flowing from a house back into a muni system.

I would think that the ability of muni water mains to supply (or absorb) btus would be overwhelmed during severe weather if many homes (and businesses) started using the mains as geo loops.

OTOH a supply and reinjection pair of wells serving 10 or 100 homes would probably work quite well (pun intended), spreading the cost of the infrastructure over many homes would likely result in capital costs a small fraction of the cost of a pair of wells for each home.

 

30000 btus could average 3,000 gallons/day depending on things.

Our friends in Minnesota were looking at using a common water supply on the reservation. Dunno if they ever proceeded with it.

 

So I have confirmed with the municipality that there is no bi-law regarding this and to my excitement they thought is would be a good idea for me to try. I made sure they understood the amount of water I would be taking out and dumping into the drain. It didn't raise any concerns at all and they commented on the large infrastructure and water supply that is available. One of the blessings of living in a area of bounty. So I am sure this will generate loads of discussion, and I look forward to the comments.

 

In my AO they meter in-coming treated, ready to drink water from the city supply lines. They charge us for the amount we use/buy. The city then adds, a like as used amount for waste water treatment, based on the incoming volume of water. The water goes someplace. When that billing is complete they, the city, factors in a new tax for storm water assessment. Rain water needs to go someplace, too. The city charges all of this based on the amount of water coming into the home.

So we have at least three factors for our "water bill". I look out my window at Lake Erie, but I can not see CA. We are not able to send Dewayne Dean any of Lake Erie, due to treaties with the Navajo or CA and other Inland sea States, (Think the old Great Lakes, that we learned in school).

I tend to think in quality of water. What can you do with it?

Drink it = very important = must have even on Mars.

Flush toilets = very important = must have even on Mars = good sanitation = must have because without it we could kill ourselves, and do.

Water plants = very important = must have even on Mars = We eat plants and we eat animals that eat plants for us.

Water is the new OIL. Take care, but beware.

Mark

 

Ok now that I have confirmed with all authorities I am ready to proceed, can someone suggest a unit that would fit the build of 30000 btu loss?

 

I am sure they loved the ideas of you using the Municipal water for Geothermal then dumping it back into there drains. They are probably counting thier dollars as we type this. You will be in the market for a closed loop very soon when your water bills start rolling in.

 

This thread is titled "Municipal Geothermal Loops"...If the water originates from the water utility's supply pipes and is returned to the sewers, it's not a "loop" in any but the most liberal (planet earth as a loop) sense.

If Dan and I understand your design correctly, you are about to be financially killed by muni water bills. Look at the rate structure and do the math. Chances are you can cost effectively accept or reject no more than 300 or so Btu per gallon (~2500 Btu / CF) of muni water. If you need, as is typical for a home, tens of millions of Btu per year heating and / or cooling, the financial numbers fall apart fast.

 

It could be titled "municipal Open Loop".....most of my open loop customers go through 600kgal to a million each year. I have one small municipality nearby that charges a flat quarterly fee. This'd work great there.

 

There is no cost no matter how much water I consume. Wondering if someone can suggest a design or point me in the direction. Much appreciated. Once I get up and running I will provide an update.

 

I would think this would be temporary pricing. The owner of the water company will no doubt come up with a new pricing scheme when they realize the amount of money they are missing out on.

 

How do you want to distribute the heating and cooling? Do you need 30K or 300K?

Mark

 

"Wondering if someone can suggest a design or point me in the direction."

Start with manual J load calc.

 

Mark I have calculated my heat loss to be 30000. I will be distributing heat only into a hydronic radiant floor heat system. That is currently supplied hot water from an electric boiler, so I will need to tie into that as I want to keep the boiler as a secondary supply. My current electrical costs during the November-April timeline is approx. 600 per month. Outside of those months there will be no use as cooling is not necessary in this climate.

 

with open loop you need as little as a 2 ton WTW dunno what the design city is. You would have the WTW geo heat a buffer tank (30 gallon would do but 40 or 50 will be cheaper to buy) and plumb electric boiler down stream of the tank for aux or emergency use.