[pmb1010]

Yes, just last year our main HQ installed a natural gas, liquid cooled 20kw 3 phase unit. on my recommendation.

There are many things to consider.
Businesses sometimes need 3 phase power, so the "standard" generator typically won't do. Make sure it's sized to the requirements of the devices to be operated. Although our system runs our network, computers, - the outside connections depend on the local phone company to provide a data connection (Verizon) to the central phone office, and from there to AT&T for Internet connection. This is especially true of Cable TV internet connections. They most likely will not operate in wide area power outages.

If the power goes out the data connection might be lost due to loss of power on the poles for signal repeaters that are there, which exist to get the signal from you to them. Also, the requirement for UPS's doesn't go away, as generators do not pick up the instant the power goes out. They have detetection devices in their transfer switch circuitry, with built in delay to ensure the generator doesn't cycle on and off during minor electric blips. In our situation, we had to replace the critical UPS's as the new generator doesn't give 100% clean 60 cycle power signal, and the old UPS's would click on and off. New ones (expensive ones) with better inverter circuitry solved that issue.

Gasoline generators, having gasoline on hand can be dangerous. This is what I do for my home, I keep 5 ea 5 gallon gas cans on hand, with gas stablalizeer in it. Every couple months I'll dump one of them thru the cars to keep the gas fresh. Remember that gas pumps at gas stations won't operate without power. So getting gasoline during an outage can be an ordeal.

With Natural Gas, the big units use a LOT of gas. You might need bigger pipe from gas company, and they must provide enough pressure that you'd draw to operate your generator for your business. Make sure they come out and test your connection so you have the necessary flow & pressure. And with gas, be aware that Natural gas has electric powered "repeater pumps" along their lines periodically. If there is a area wide outage, your gas pressure might drop below requirements for your generator. Something to consider.

Hospitals & Police stations use generators with Diesel fuel. Less troublesome than gasoline, but now you have the ssue of replishment. Make sure if you go this route, that a contract is setup with a company to come bring you diesel on a periodic basis if there is a long outage.

And home users, please do it right and install the correct manual transfer switch for gas gererators at your panel. Pick 6 or so things you need (sump, freezer, fridge, furnace, some lights) and put those on the switch. Please do not backfeed a breaker in your panel. That is dangerous, illegal in many places, and not safe for the workers trying to restore power in your neighborhood. In some locations (Calif I think) you can be found criminally liable if someone is hurt due to backfeeding breaker panels.

Please be safe.