Substation Size/Cost Estimate 1

[EEJaime]

Gentlemen,
We have been asked to provide a couple of options to our client by the utility company for a project. One option involves the addition of an on-site 66kV to 12kV substation to feed a load of about 5500kVa at 12kv. Since this is not my area of specialization, I thought perhaps one of you whom is involved more frequently with this type of distribution would have a feel for this.

Basically I need preliminary information, just rough order of magnitude estimate of what kind of cost we are looking at and how much real estate this might take up. I believe that the 66kV will be brought in overhead and the 12kV secondary will be distributed underground to backfeed an existing 12kv Utility service switchboard. We need to give the owner an idea of the impact this change will have on his campus.

As always any information is greatly appreciated.

Regards

 

[wareagle]

How many breakers? Will you have a LTC regulator?
The utility should be able to give a guestament of cost?

 

[EEJaime]

Wareagle,

The substation will have a main and two feeder circuit breakers all at 400A. That's the largest service that Southern California Edison wants to give the customer. The two load breakers are to feed a single 400A site loop which feeds loop feed selector switches at various buildings. We should assume that there will be an LTC regulator and full metering package for metering service at 12kV. This will be in an outdoor enclosed yard, to all will be weatherproof.

Thank you,

Jim Murillo

 

[wareagle]

Jamie
That will be a difficult job to come up with an estimate if
you are not in that area of work. When I was with a utility
we had a packaged estimate that had been prepared by the sub group. Each sub is different. That's why I suggested that you get with a utility and use their packaged estimate for your particular job.

 

[apowerengr]

Sub w/ main and two feeders is $1M US assuming the primary protection is power fuses and not a circuit breaker/circuit switcher. Site requirements are roughly 1 acre depending on feeder configuration. This also assumes 5//7 MVA power transformer and no spare.