induction vs. synchro gensets 1

[popeye]

Our company is looking at ways to power remote locations with minimal 480v power (50 to 300kw) and sell back the unused portion to the utility. Our applications require 24/7 operation with natural gas engines (casing gas) or diesel power - Anyone have some history with these systems and/or directions?

 

[peterb]

An induction genset will work fine for this application, with all the benefits of simplicity of operation - you save on supply & maintenance costs of excitation & synchronizing equipment.
I designed an installation of 2x500 kW natural gas engines for cogen service with induction generators, no known problems after 9+ years in service. The utility interconnect was also simpler with this arrangement, as there is no continued backfeed into utility side faults.

The downside of course is that there is no standby supply if the utility fails, as you need that supply for your excitation. If you absolutely must have 24/7 uninterrupted supply, then you need to go with a synchronous generator with appropriate controls & intertie protection to ride through utility outages - you will also get a boost in power quality with this arrangement, as voltage control will be tighter.
One thing to watch for with the induction option - you will probably need to install power factor correction capacitors, which should be sized so that they don't improve the no-load PF beyond 1.0 lagging. This is to avoid self-excitation of the induction generator.

 

[SooryaShrestha]

What is 24/7 operation? Somebody please explain.

 

[jbartos]

24 hours per day and seven days per week. It may tacitly be assumed 365 (or 366 days) per year; however, this is missing in the 24/7 expression. Perhaps, it will be better to write 24/7/365 to have it more conspicuous. Also, some time is supposed to be reserved for the scheduled maintenance.

 

[berrytc]

Popeye,
Our company builds the power generation equipment you need for converting casinghead gas to electricity. We have both synchronous and induction units fueled by natural gas, casinghead gas, landfill methane, etc., and have placed these units in numerous 24/7 "oilfield" situations. We would be pleased to visit with you further about our equipment. You can call us at 505-623-3700 and/or visit our website at

http://www.genergypower.com.

 

Our company builds power generation equipment that uses our own generator/utility controller . In fact, we specialize in your type of application. You can visit our web page

http://www.encorp.com

or call 970/686-2017.

 

[MarcL]

Do you have available pressure differential at your remote location? If so you may wish to consider an expansion turbine driven generator rather than burning the gas.

 

[MarcL]

For more information on expansion turbine/generators see our web page at

http://www.mafi-trench.com

or call us at 805-928-5757 for details.

 

[jbartos]

Suggestion: Considering that the gas is dwindling and prices are going up, and that the gas is chemically the very valuable commodity, it appears that some alternate solution might be investigated.