Using a submersible pump to CREATE electricity?

[SuckerRod]

Hello!

I was wondering why you couldn't put a submersible pump at the bottom of a disposal well, run it backwards and CREATE electricity?

Seems like it would work, but I don't know much about sub. pumps either?

Anyone tried it?

Regards,

SuckerRod

 

[DrillerNic]

Why not put the pump/ turbine on the surface, where it's much easier to get at? Unless there's a specific reason to generate electricity down hole?

 

[zdas04]

I've heard this one before: on an injection well that goes on vacuum, you can flow from a tank into the well without pumps and then use the potential energy of the height difference to do work with the "alternator" downhole. Line losses, friction, etc. make this a net gain only if you don't need an injection pump, so it only works as long as the well goes on vacuum.

The economics I saw in the '80's said that the lash up would never return the capital cost of the pump, tubing, cable, and installation. Electricity is more expensive now, but I don't think it is enough more to ever pay out.

David Simpson, PE
MuleShoe Engineering

http://www.muleshoe-eng.com

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

The harder I work, the luckier I seem

 

[jmw]

Somewhere in Wales is a mountain with a lake/reservoir at the top.
Water is pumped up during off peak times and during peak times is allowed to flow back through turbine to generate electricity.

JMW

http://www.ViscoAnalyser.com

 

[buzzp]

Pumped storage has been around for quite a while. However, this is a bit different since most 'penstocks' for submersible wells is around 4"-6" compared to >15' for penstocks. Of course, the same principles apply but you may need a dead well to run the water back down too rather than your producing well. Here in the west the CBM fields are having issues over what to do with the extracted water. Maybe some innovative company should pursue this idea to use the electricity within their own field (cost to ship out to grid is likely to high to consider but certainly could use to run field equipment).

 

[SuckerRod]

That's what I'm looking to do, buzzp. I don't intend to generate enough electricity to sell, per se, but if I could create just a little to offset our current electrical costs in the field, I might be able to save a little $$$...

 

[buzzp]

SuckerRod,
I used to work in the oil fields doing field service. I can tell you the places I worked had terrible power sources. Generally, these fields are away from any appreciable power generator and the fields suffer. I can remember seeing a whole field of 480 volt motors running on ~ 420V due to voltage drop. And the unbalance was even worse. If I were managing the field, the first thing to get fixed would be the power source. Sometimes its a result of the electricians, sometimes the utility. I would say an appreciable savings could be obtained by providing these motors with close to nameplate ratings for power (motors more efficient this way). Every field had issues with their power that I visited (Wyoming, Colorado, and Utah).
I would say your idea has some merit and would be worth investigating. Of course, the flow would have to be controlled through the generator.
Are most sites still dumping the water on the ground or are some injecting the water back down hole?
The oil guys want the oil out now with little consideration to efficient operations. Afterall, oil is pretty spendy now. I realize the cost savings of an efficient field but it seems many others don't realize the savings or don't care since the savings is might be negligible compared to the oil/gas production. However, I believe a decent sized field could save at least 5-10% on their electric bill by assuring these motors have good power.

 

[SuckerRod]

Thanks for the info, buzzp.

Right now, no one cares about saving a few bucks on expenses. We're just trying to get every well pumping SOME oil, and don't care about efficiency.

We have an old field that makes 10,000 bbls of fluid PER DAY, with little gas and 50 bbls of oil. Getting rid of the water is a BIG deal, and we are injecting it all back into the formation. If we could handle more water, we could make about 60 more barrels of oil per day (and at $60/bbl...). Needless to say, we need to get rid of the water, someway, somehow.

We have to dispose of or inject all the produced water. I don't know of any well that doesn't contain enough chloride to kill off old farmer Johns wheat field. The EPA frowns, penalizes, fines, etc ANY water that is not handled properly (i.e. spilled).

I think the idea has merit too. Most of our injectors are taking the water on a vacuum. If we stick a sub in the hole to generate electricity, it might backfire and block the hole enough to the point where we'd have to pump it under pressure, and there go your savings.

But if you could put a sub pump at the bottom of the hole, and still have the water flow on a vacuum, you "should" be able to create enough electricity to run SOMETHING, depending on the voltage.

There is a reason this HASN'T been done yet. I am looking for why.

Regards,

SuckerRod

 

[buzzp]

I dont think you want to drop the water in the same hole due to the need to pump the water back out at the same spot to get the oil or gas. You would need a seperate hole for dropping the water down to maintain your vacuum and to assure you are not repumping out the same water you dropped down. This may or may not be a big deal depending on if there are any capped wells around to use (certainly would not want to drill a new one just to pump water down). I could see this affecting the vacuum too, in some cases, depending on the formation. I am no petroleum guy to understand formations, does this sound right? How deep are the wells you deal with??
Around Wyoming and such there are several sites that drop the water on the surface. I know its not the best water but some farmers welcome it (gives them a reservoir they never had) but some people says its really destructive to their fields. I do believe the cows and other farm animals can drink the water they are pumping around here but I could be wrong. However, I do know several sites are not injecting the water back down hole. Alot of political rebuttle going on now about this very issue.

 

[SuckerRod]

What we'd do is use an existing injection hole that is taking the water on a vacuum. We would never consider pumping water down a producing hole (especially at $60/bbl!).

Theoretically, the idea should work, it's just a matter of figuring out whether dropping a pump in the hole will kill the vacuum or not...