Getting our first generator

[RobWard]

We are building a new factory and want to get a back up generator.

This would run on natural gas, for various reasons.

I've no experience of generators, only what i can glean off the web.
I'm wondering what questions I should put to potential suppliers.

We need to have back up power in case of a mains outage, as, if power fails during some critical operations, our equipment will break, and we'll end up junking some very expensive products also.

We're also likely to be getting very close to our supply limit on occasions (220kVa) so I wondered what the consensus on load shaving was.

Sadly it seems, from reading manuacturers websites, that a gas turbine powered genny isn't really applicable here.
I rather fancied having a jet engine to play with. Shame.

Any thoughts, or suggestions would be very kind.

Regards,

Rob

"I love deadlines. I love the whooshing noise they make as they go past." Douglas Adams

 

[RobWard]

Well, drat!
Have spoken to some CHP people and it looks like there would be a problem getting useable heat into our process.

My only other thought is that the factory heating needs to be radiant.
We were looking at electric radiant heaters for a few reasons, but if we could use the ehaust from a, say, 300kVa turbine powered genset as a source for some gas powered radiant tubes, then everytime we had the heating on we'd get some "free" electricity, although we'd have to vent the unwanted heat in the summer if we needed to run the generator.

I just like the idea of my own jet engine, ok....


I'll speak to some generator people in the next few days to price up regular back up generators, but I need to get a better picture of our power demands first I think.

Thanks for all the help, people.

Rob

"I love deadlines. I love the whooshing noise they make as they go past." Douglas Adams

 

[waross]

Re block loading and resistance heaters.
Most of the genset installations that I do have a lot of large airconditioning loads. Resistance loads are very tame compared to motor starting.
Re natural gas, Many years ago, I worked on the construction of a new department store. The cash registers were computer terminals. The computer technology of that day required each terminal/cash register to download it's operating program from the main frame each day. Quite fast for one terminal, but very slow if all the terminals were trying to restart at once.
We had a standby generator powered by a chevrolet V-8 converted to natural gas. The terminals had large capacitors in the power supplies and could withstand a power outage of about 8 seconds. We set the timers as low as possible and were able to get the set started and online quick enough to consistently keep the terminals online.
Waste heat. If you use can hot water look for a second hand boiler. Blow the exhaust through it. Use the water to supply your normal water heaters with preheated water. Lots of hot air from the radiator. It may be ducted to work areas in cold weather. If air quality is an issue, the radiator may be seperated from the engine to avoid possible exhaust or oil fumes.
Re peak shaving, without knowing the economics, my suggestions may or may not be feasible. The transfer switch method sounds good. Consider more than one transfer switch.
Depending on the relative costs of gas and peak penalties, you may want to load the generator in steps. Also, you can reduce block loading by transfering the critical load immediately and follow with the noncritical loads at short intervals. There are very cheap, two wire timers available in the refrigeration induustry. Just put one in series with a coil and set the delay.