Cost to provide temp generator during planned utility outage?

[malachi constant]

208V/3p/4w 1600A service. Approximate load of 100kW, they could shed as necessary to get through the day. Would open up the main switchgear and attach straight to the lugs.

I'm not providing all the details, but have asked around and believe this is legal. I thought I could get a cost out of Means but evidently not. Looking for a very ballpark estimate - this is for a preliminary study of various options, not a bid, not a detailed construction estimate. Thanks!

 

[petersonra]

208V/3p/4w 1600A service. Approximate load of 100kW, they could shed as necessary to get through the day. Would open up the main switchgear and attach straight to the lugs.

I'm not providing all the details, but have asked around and believe this is legal. I thought I could get a cost out of Means but evidently not. Looking for a very ballpark estimate - this is for a preliminary study of various options, not a bid, not a detailed construction estimate. Thanks!

I think it is code wise OK.

you should not have a lot of trouble figuring out what it will cost to rent the generator. A lot of places rent generators. You can probably get one for $500 for a day including delivery and pickup.

fuel wise, 100kw is roughly 10 therms per hour after the efficiency of the generator is taken into consideration.

you should be able to fiind out what your customer pays for natural gas and go from there.

100 kW seems like a lot of load shedding to be doing on a 1600A 208V service.

don't forget the cost of the plumber to come out and hook it up and disconnect it afterward.

 

[qcroanoke]

208V/3p/4w 1600A service. Approximate load of 100kW, they could shed as necessary to get through the day. Would open up the main switchgear and attach straight to the lugs.

I'm not providing all the details, but have asked around and believe this is legal. I thought I could get a cost out of Means but evidently not. Looking for a very ballpark estimate - this is for a preliminary study of various options, not a bid, not a detailed construction estimate. Thanks!

2008 NEC: 702.6 exception
Makes it a legal hookup.
Iwire's company has done it several times.

 

[John120/240]

I think it is code wise OK.

you should not have a lot of trouble figuring out what it will cost to rent the generator. A lot of places rent generators. You can probably get one for $500 for a day including delivery and pickup.

fuel wise, 100kw is roughly 10 therms per hour after the efficiency of the generator is taken into consideration.

you should be able to fiind out what your customer pays for natural gas and go from there.

100 kW seems like a lot of load shedding to be doing on a 1600A 208V service.

don't forget the cost of the plumber to come out and hook it up and disconnect it afterward.

malachi states it is a planned one day outage. So petersona what would be the benefit of using a natural gas unit ? If a diesel unit was used there is no need for a plumber to connect the natural gas.

 

[petersonra]

malachi states it is a planned one day outage. So petersona what would be the benefit of using a natural gas unit ? If a diesel unit was used there is no need for a plumber to connect the natural gas.

A diesel generator requires a source of diesel. At full load you are looking at close to 10 gpm. might well need a tanker with the generator.

you might have to get a special permit to use a diesel generator for emissions.

you might also have to do something to prevent spillage of diesel, like some kind of temporary dike.

NG is much simpler if it is readily available.

 

[iwire]

A diesel generator requires a source of diesel. At full load you are looking at close to 10 gpm. might well need a tanker with the generator.

you might have to get a special permit to use a diesel generator for emissions.

you might also have to do something to prevent spillage of diesel, like some kind of temporary dike.

NG is much simpler if it is readily available.

OK, if you are using a diesel that is taking 10 GPM (and it won't at the load the OP is talking about) how many cubic feet of gas per minute would it need and do you think the buildings gas service can provide it? Assuming it has gas service.

Also how many thousands would hard piping that kind of flow cost?


No one would use a natural gas temp generator for this type of thing.

 

[John120/240]

A diesel generator requires a source of diesel. At full load you are looking at close to 10 gpm. might well need a tanker with the generator.

you might have to get a special permit to use a diesel generator for emissions.

you might also have to do something to prevent spillage of diesel, like some kind of temporary dike.

NG is much simpler if it is readily available.

At 10 gpm I see how natural gas would make sense. Thank You

 

[petersonra]

OK, if you are using a diesel that is taking 10 GPM (and it won't at the load the OP is talking about) how many cubic feet of gas per minute would it need and do you think the buildings gas service can provide it? Assuming it has gas service.

Also how many thousands would hard piping that kind of flow cost?


No one would use a natural gas temp generator for this type of thing.

Its pretty close to 10 gpm. A gallon is about 110,000 btu which is only a little more than a therm.

cost depends on how far you have to pipe it from a high pressure source. if you are near the meter, it might not cost much at all.

It is application driven. you might have to put in another pressure regulator. that could get messy.

 

[iwire]

At 10 gpm I see how natural gas would make sense. Thank You

10 GPM in diesel would be huge. The one megawatt units we rent can run about 100 - 120 gallons per hour if fully loaded.

Here is a 1 meg unit.

But let's keep in mind the OP mentioned 100 kw as the load.

 

[iceworm]

Its pretty close to 10 gpm. .

But let's keep in mind the OP mentioned 100 kw as the load.

12 gallons/hour should be a good number.

Fill the DG tank (100G?), 4 drums and a 12V pump in the back of a pickup will do it.

just a thought: Outfits I work for like a containment under the generator/refueling area. 4x4 frame and poly coated geotextile.

Pay attention to the N-G bond in the generator. Probably want to make sure it is removed.

ice

 

[petersonra]

12 gallons/hour should be a good number.

Fill the DG tank (100G?), 4 drums and a 12V pump in the back of a pickup will do it.

just a thought: Outfits I work for like a containment under the generator/refueling area. 4x4 frame and poly coated geotextile.

Pay attention to the N-G bond in the generator. Probably want to make sure it is removed.

ice

most places will require some kind of containment. at least most places I have seen it done.

 

[petersonra]

10 GPM in diesel would be huge. The one megawatt units we rent can run about 100 - 120 gallons per hour if fully loaded.

Here is a 1 meg unit.

But let's keep in mind the OP mentioned 100 kw as the load.

100 kW = 341,200 btu/hr

at 33% efficiency that is not far from 1,000,000 btu/hr

a gallon of diesel is about 110,000 btu

my back of the envelope calculations probably overstated the efficiency of the generator, but it is not real far off from 10 gph at full load.

I actually did mean gph and not gpm. not sure why i wrote gpm.

 

[John120/240]

I actually did mean gph and not gpm. not sure why i wrote gpm.

That does make a whole lot more sense. Thank You

 

[iwire]

GPH makes much more sense.


That issue aside, we do this type of thing many times a year.

1) EPA, not an issue for temp gensets (Assumes the rented genset complies with EPA requiments)

2) Containment, not an issue for temp gensets

3) Using a natural or bottled gas unit for temp. Never done it, never seen it and I don't know if I could rent one if I wanted.

 

[iwire]

208V/3p/4w 1600A service. Approximate load of 100kW, they could shed as necessary to get through the day. Would open up the main switchgear and attach straight to the lugs.

I'm not providing all the details, but have asked around and believe this is legal. I thought I could get a cost out of Means but evidently not. Looking for a very ballpark estimate - this is for a preliminary study of various options, not a bid, not a detailed construction estimate. Thanks!

Yes what you propose is legal, we do it often. I would bring at least a 200 KW genset for your 100 amp load just so there is some headroom for starting motors etc,

I am sorry I can't say much about costs, I just call our office and have them handle the rental of whatever size we need.

Here is a 1 meg we did at 1AM in a stone quarry so that paving work on an interstate highway project could contiue.

Here are a couple from a scheduled shutdown at a hospital, we used three units, I can't recall why.

Another 1AM job during a storm

This is the tie in, this service did not have a single main to open so we had to open the cutouts, lift the service conductors, isolate them and tie in at that location. This means having the power company come out after power is restored to kill it again so we can put the service conductors back.

 

[iwire]

most places will require some kind of containment. at least most places I have seen it done.

I have never in my life seen external containment required for a temporary generator.

Permanent generators for sure, but not temp.

 

[iwire]

Pay attention to the N-G bond in the generator. Probably want to make sure it is removed.

I will be honest, we leave the bond in place.

 

[iwire]

Another at a water pumping station

This ones below we were working for a utility feeding some sort of building for them during an outage

In this case we could go right into a power company vault for the tie in.

 

[growler]

you should not have a lot of trouble figuring out what it will cost to rent the generator. A lot of places rent generators. You can probably get one for $500 for a day including delivery and pickup.

I would bring at least a 200 K

I am sorry I can't say much about costs, I just call our office and have them handle the rental of whatever size we need.

I don't know what the rental cost would be either but for a one day rental on a piece of expensive equipment they normally really jack up the price so I'm thinking a lot more than $500 to rent a big enough unit.

 

[iwire]

I don't know what the rental cost would be either but for a one day rental on a piece of expensive equipment they normally really jack up the price so I'm thinking a lot more than $500 to rent a big enough unit.

$500, that is funny.