On Monday, February 17, 2014 8:59:15 AM UTC-5, (PeteCresswell) wrote:
Per NotMe:

As a rule of thumb NG generator produce ~80% of the power using the same engine as it does on liquid gas.



Also depending on the reason for electric outage you may not have NG feed to the house.



The installs we have use NG as primacy, LP as secondary (while

expensive does not go bad) and liquid gas. Regardless of the

type of fuel sources can be interrupted.



The key is the duty cycle and requited operating time.



Thanks for the succinct and definitive reply.



What is your experience with how long propane tanks themselves last?

i.e. they are steel and steel rusts.... Anything over 10 years would

effectively be "forever" in our case.



What I'm thinking is something set up for nat gas with a manual cutover

switch to a tank of propane in the event that worse comes to worst.



OTOH, that would seem to require a longer run for the nat gas line.

Without the propane backup, the gennie could be as close to the house as

zoning allows. With propane backup, I would think it needs to be away

from the house (as in the garden shed or something) for safety reasons

in case of a house fire.



Or am I over thinking this?

--

Pete Cresswell

You apparently have nat gas. In 30 years with nat gas, I've had
many power outages from a few seconds, all the way up to Hurricane
Sandy, where power was out in much of the region for up to a
week+. Never lost nat gas once.

I guess whether you're over thinking it depends on what
exactly you need the backup power for, what kind of worse case
event you want to protect against, and the liklihood that
nat gas would go out at the same time. I guess in an earthquake
area, there the gas system would be more vulnerable. But
in most of the prime earthquake areas, eg CA, the climate is
such that needing the generator for heat isn't nearly as
great as it would be in WI, so one important need is lessened.
I would think for 99% of the
folks using backup generators, having nat gas as a fuel would
be more than sufficient and the cost, having an ugly propane
tank, etc wouldn't be worth it.