Geothermal in power trench...Doable or Not?

[955Lincoln]

I have to check if the power company will allow this, probably not. I need to dig an 1800' trench for power and I was thinking how nice it would be to slip 3600' of geothermal in there. Power companies will allow lots of stuff in the same trench but I think they want their cable to be on the bottom. The trench will be 12" wide and 3' deep for the power. What if I could increase that depth to 5 or 6' and put the geothermal on the bottom with a welded u-turn at the end of the run? A lot more digging but less if you combine digging time for both projects together. I would have to abandon the line if it ever leaked. What do other geo owners do if their lines leak?

Harebrained idea or feasable?

 

[KennyG]

Usually local code will address this for underground utilities. My guess is you will find that water and electric in a common trench is OK if they are separated by about a foot.

The power company will probably not want anything to do with this though.

 

[gwjd]

all i have to say is get a big!!!!!!!!! trencher for this project

also will you get the proper temp at 5-6 feet?

 

[BruceWard]

As long as it is separated by more than a foot my local electric company would not mind. They would not know either as the goethermal loop would need to be installed and backfilled before the electrical.

If you are going to install both you could save by putting them in the same trench.

Otherwise the 3' electrical trench could be a 1' wide trench with you or the conduit installers working from above. The 6' goethermal trench will need to be much wider to allowing working room plus be wide enough to avoid cave ins killing the crew.

 

[dstig1]

I'd say you are asking for trouble. If you ever need to repair that pipe, how are you going to dig under your power cable to get to it? BZZZZT!!! I could see 2 parallel trenches next to each other or a single much wider one, with a deep side for the pipe and a shallower side for the cable, and then they are not on top of each other. Digging around the main power feed for the house sometime down the road is not something I would want to do though I suppose if it came to that you could just abandon the pipe and put a new one in elsewhere on the property.

 

[MikeInMaine]

Most power companies print handbooks of their requirements. Ours has diagrams of various trench configurations showing the amount of vertical separation or horizontal separation required in shared trenches, depending on whether you wish to dig your trench deeper or wider. It it probably allowed, so just make sure that you do what's in their diagram. These shared trenches may have water and gas lines.

Sometimes the information may be in a packet the utility provides for new customers. Also some excavation contractors have these handbooks, as well as electricians.

I recently put in some underground power for a customer, and the excavator used a 6' wide bucket. There was plenty of room across the bottom of the trench for electric, telephone, cable tv, and a 2" pipe for irrigation.

 

[955Lincoln]

Usually local code will address this for underground utilities. My guess is you will find that water and electric in a common trench is OK if they are separated by about a foot.

The power company will probably not want anything to do with this though.

I'm the unfortunate soul who will be digging the trench and installing the power conduit.

 

[955Lincoln]

also will you get the proper temp at 5-6 feet?

Dunt know.....that will be a good place to start my research.

 

[955Lincoln]

The 6' goethermal trench will need to be much wider to allowing working room plus be wide enough to avoid cave ins killing the crew.

Good point. I wonder though how much trench entering would need to take place for laying 2 plastic pipes in the bottom of the trench?

 

[955Lincoln]

I'd say you are asking for trouble. If you ever need to repair that pipe, how are you going to dig under your power cable to get to it? BZZZZT!!!

Yuppers! I mentioned in my post about having to abandon the run if I sprung a leak. Do you know what people do if their system leaks? Dig up and repair or start another? Neither option sounds very fun. :laughing:

Power cable aside....just finding a leak in a 1800' run would seem impossible.