Availability of Natural Gas during Blackout
Some weeks back there was a dicussion on the merits of naural gas versus diesel generators. It is my observation that Natural Gas continued to be available throught this recent blackout. In speaking to a friend who works for the gas company he informed me that the compressor stations on the main pipelines are driven by gas turbines, thus they don't require electrical power to operate. All telemetering/control equipment on the distribution network is either passive, or equipped with natural gas generators to ensure it operates. Did others notice if there was a gas interuption in your area during the blackout ? (A lot of people here were cooking on their Nat. gas bbque here) This was an exceptionally long blackout, did people have trouble getting diesel fuel replenished? Fuel trucks where no doubt having difficulty with traffic congestion due to traffic lights not working. Regards, Randy
There are a couple of problems with Natural Gas generators: 1. It takes an aweful lot of pressure to get a NG engine up past enough HP to generate more than say 150KW. At least thats what we have seen with current models. It seems to be an issue of pressure, and whether being fed from a pipeline or coming from a tank separte (electric) compressors are almost always needed. 2. In times of weather emergencies, snow and excessive cold, the gas companies routinely shut down gas flow to non-residential areas (like where you would put datacenters) to assure heat for people's homes. This bit me personally in a a very minor way a few years back in a region as far south as McLean, VA. We had a small kitchen with a gas stove in the office and when we got snowed in one night it was shut off. If the gas supply had been powering the backup generator for our datacenter it would have been ugly as the electrical power went out a few hours later. On the other hand, LNG in tanks is a bit more reliable in the snow if you have a large enough tank to provide pressure during cold whether and to get you by during a prolonged snow emergency. In our transmission shelters which are spaced aout 50 miles apart along the fiber right of way, we always try and use LNG generators because they don't have cold start problems the way diesels do, they just fire up. And the power needs for the repeater stations in < 65kw so we dont need to worry about the limit in size on LNG engines. -vb ----- Original Message ----- From: "Randy Neals (ORION)" <randy.neals@orion.on.ca> To: <nanog@nanog.org> Sent: Sunday, August 17, 2003 10:51 AM Subject: Availability of Natural Gas during Blackout
Some weeks back there was a dicussion on the merits of naural gas versus diesel generators.
It is my observation that Natural Gas continued to be available throught this recent blackout. In speaking to a friend who works for the gas company he informed me that the compressor stations on the main pipelines are driven by gas turbines, thus they don't require electrical power to operate. All telemetering/control equipment on the distribution network is either passive, or equipped with natural gas generators to ensure it operates.
Did others notice if there was a gas interuption in your area during the blackout ? (A lot of people here were cooking on their Nat. gas bbque here)
This was an exceptionally long blackout, did people have trouble getting diesel fuel replenished? Fuel trucks where no doubt having difficulty with traffic congestion due
to
traffic lights not working.
Regards, Randy
Speaking on Deep Background, the Press Secretary whispered:
There are a couple of problems with Natural Gas generators:
1. It takes an aweful lot of pressure to get a NG engine up past enough HP....
True; you need to engineer well. And not all sites will have a sufficent main.
2. In times of weather emergencies, snow and excessive cold, the gas companies routinely shut down gas flow to non-residential areas
This is a contract issue; Commercial customers often get better rates for being 'cutable'... but you need to assure the generator is not one.
On the other hand, LNG in tanks is a bit more reliable in the snow if you have a large enough tank to provide pressure during cold whether and to get
LNG tanks for any big installation will be BIG. You'll have to pay to keep all the LNG in stock. Propane has another issue -- it can get too cold for it to vaporize, leaving you really SOL. -- A host is a host from coast to coast.................wb8foz@nrk.com & no one will talk to a host that's close........[v].(301) 56-LINUX Unless the host (that isn't close).........................pob 1433 is busy, hung or dead....................................20915-1433
2. In times of weather emergencies, snow and excessive cold, the gas companies routinely shut down gas flow to non-residential areas
This is a contract issue; Commercial customers often get better rates for being 'cutable'... but you need to assure the generator is not one.
This is true as long as no emergency is declared. If a state of emergency *is* declared (yes, Nortern Virginia declares a state of emergency for snow flurries) contract or not, commercial customers get cut if the gas is needed for residences.
On the other hand, LNG in tanks is a bit more reliable in the snow if you have a large enough tank to provide pressure during cold whether and to getc
LNG tanks for any big installation will be BIG. You'll have to pay to keep all the LNG in stock. Propane has another issue -- it can get too cold for it to vaporize, leaving you really SOL.
Yes, thats why only small (again sub 65KW) installations make sense. And from experience, we have had -22F in Lancaster, PA and our propane genset started right up. That the coldest we have on record at any of our sites though during a utility outage.
-- A host is a host from coast to coast.................wb8foz@nrk.com & no one will talk to a host that's close........[v].(301) 56-LINUX Unless the host (that isn't close).........................pob 1433 is busy, hung or dead....................................20915-1433
participants (3)
-
David Lesher -
Randy Neals (ORION) -
Vincent J. Bono