Our school has a bunch of little cummins (like 6 of them) "Orion Gensets" that can make about 125kw each (plenty for an individual building on a school campus) I think the one on our main building (its big) makes 200-225kw....as that building has our data center in it.

One building also has an older (probably 20+ years old) nat gas generator. We had the power fail on campus a month ago or so when it was about -5F outside.....The nat gas generator fired right up and was running very quietly. The larger Diesel Genset's powered up ok, but one of the smaller ones wasn't able to start. It was the one outside the maintenance and physical plant building. So no internet connection for 2.5 hours.

Our new fancy library has one of the GIANT CAT generators.....its got to be 15' long and 12' high with a ginormous fuel tank. I've heard it running once, it sounded fierce!! The muffler/exhaust on that thing must be 4' around!! Most of them on campus seem to run for about 45-60 mins every few weeks.

__________________
-diesel is not just a fuel, its a way of life-
'15 GLK250 Bluetec 118k - mine - (OC-123,800)
'17 Metris(VITO!) - 37k - wifes (OC-41k)
'09 Sprinter 3500 Winnebago View - 62k (OC - 67k)
'13 ML350 Bluetec - 95k - dad's (OC-98k)
'01 SL500 - 103k(km) - dad's (OC-110,000km)
'16 E400 4matic Sedan - 148k - Brothers (OC-155k)

So how long can the data center run on the fuel you have on-hand? 12,000 gallons at today's prices!! Thats like $45,000 of fuel!

__________________
-diesel is not just a fuel, its a way of life-
'15 GLK250 Bluetec 118k - mine - (OC-123,800)
'17 Metris(VITO!) - 37k - wifes (OC-41k)
'09 Sprinter 3500 Winnebago View - 62k (OC - 67k)
'13 ML350 Bluetec - 95k - dad's (OC-98k)
'01 SL500 - 103k(km) - dad's (OC-110,000km)
'16 E400 4matic Sedan - 148k - Brothers (OC-155k)

If they produce 1.5MW then they must be over 2000hp each. At 100% efficiency 1.5MW is the equivalent of about 2011hp. So since nothing is 100% efficient they must either produce less power or be more powerful.....just me thinking aloud. Please inform me if I am wrong.....I think my logic is right but then again I don't know anything about generators.

Your logic is correct. Large generators are pretty efficient in turning shaft horsepower into electrical power. If the generator has a continuous rating of 1.5 MWe, the diesel engine probably has a nameplate rating of at least 2200 HP (just a guess). Also remember that these diesels are rated for 90F ambient air at 1 atm, so you have to correct for higher temperatures and lower pressures.

The generators have redundant electrical starters. I wasn't there at the start time, so I don't know if they preoil or not.

I'll ask about the duration on the fuel tanks as well... we have a pretty high security rating so we have to stay up a long time.

Our other site in Manhattan has a similar setup. In the big power outage in the NE a couple of years ago, a helicoptor flew down one of the rivers filming all of Manhattan dark, except the floor of our building.... 8~)

Makes my little 40kva at the house sound like a paperweight.

What RPM do the big boys turn to produce 60hz? 1800 like mine or 2400 or ??

__________________

Gone to the dark side

- Jeff

They just put one of those in at my store... Its a monster. They had to swap out the generator on it because it was faulty so they brought in another trailer mount so they could have a stand by incase of a "hurricane". They fired it up on saturday night.. I snuck out to see them fiddle with it...

I'd guess 1,500-1,800, they don't turn fast.

__________________
1999 SL500
1969 280SE
2023 Ram 1500
2007 Tiara 3200

a Cat 3412 usually has a 2000 RPM governor setting, and IIRC the 399 was 1200 RPM. The 399 is considerably larger dispacement.

__________________
H.D.B.
OBK #45
-----------------------
'75 W115 240D, wife's dd, 197K
........'75 W115 300D, my dd, 245K
.. .. ..........'82 W126 300SD, the 'someday' project

Pretty much has to be a multiple of 60. In most of Europe, they turn slower, thus their 50hz power.

__________________

Gone to the dark side

- Jeff

I still want to make a 616 powered generator.. slap on a turbo( low boost.. 5psi ish to add efficiency) and keep it on standby incase of a "hurricane"

I've seen a lot of larger ones that operate a 900 rpm, it has to be a multiple of 3600 rpm in the U.S. The bigger, the slower; the point is to maintain the optimum mean piston speed.

That's way too close, man. If you were a cat, I'd say that used up several of your nine lives.

Oldiesel's comment "...when you pushed the start switch it activated an oil pump and the starters did not crank until the oil pressure was up..." reminded me of a recent thread in this forum in which the poster wondered whether it was worthwhile to crank a M-B diesel with the FI system closed until the oil pressure came up, so as to reduce wear on the engine.

My opinion was that any gains would be more than reduced by the extra wear on the starting system. However, an external oil pump that would run during the preglow cycle, turned off by a relay when the engine was up to speed...that is an interesting idea.

Jeremy

__________________

"Buster" in the '95

Our all-Diesel family
1996 E300D (W210) . .338,000 miles Wife's car
2005 E320 CDI . . 113,000 miles My car
Santa Rosa population 176,762 (2022)
Total. . . . . . . . . . . . 627,762
"Oh lord won't you buy me a Mercedes Benz."
-- Janis Joplin, October 1, 1970

Just an oil accumulator will work, I used to have on on my TR6, can't remember the mfgr, pretty popular. It would dump it's pressure/oil into the system when the solenoid released it as soon as the key was turned on.

__________________

Gone to the dark side

- Jeff

Good point. Now that you mention it I do remember all the gen sets were either set at 900 or 1800 rpm (it's been awhile) Thanks for the refresher.

__________________
H.D.B.
OBK #45
-----------------------
'75 W115 240D, wife's dd, 197K
........'75 W115 300D, my dd, 245K
.. .. ..........'82 W126 300SD, the 'someday' project