ning
Elite Member
I just skimmed the thread, hopefully not too much repeat here.
My area gets multiple-days power outages in the summer (because of <10% humidity + decent winds = power line fires) - hopefully less as they update power lines and better maintain the ROW's - and short to medium length outages in the winter (last January, out power went out for a day, but some friends a few miles away lost power for three weeks because of the same storm).
The biggest problem with an automatic transfer switch is that it's going to use up all of your fuel in a hurry. The typical generator is not exactly sipping fuel even at idle, unless you really shell out and get a diesel. The automatic transfer switch will power up that generator at 2AM when the power fails and though you've got 300W draw in the house, you're still using 1/2gph. This is fine, if you've got 250-300 gallons available and you're only expecting to have a couple days failure. A week? It's gone and you're out of power.
For DIY-ish people, my strong suggestion is a manual transfer switch for specific circuits - water well, a couple lights, furnace/heat pump, maybe something else. You connect your generator and run it manually and it will last a long time, because you turn the damn thing off as soon as you don't really have to have power.
We've had that setup, and I ran this place during an extended power outage when there was a (very) nearby forest fire and kept our fridge and deep freeze going, plus intermittent use of the well when we came back, with a 3.5kW generator - it wasn't on all the time; we just ran it occasionally to re-chill the stuff or when we really needed to flush. It's a hassle, but a 3.5kW generator barely uses any fuel this way.
I've put a lot of thought into doing a whole-house genset (and I plan to do it), but my situation is a bit different. I've got solar, plus batteries, and the whole house automatically swaps to battery already in a grid failure.
I can set up a generator as input to this system, so that it can recharge the batteries for winter use. With this, and judicious use of electricity in the house, I figure I can weather a 30-day power grid failure with zero solar recharge, which is really unlikely to happen (on a really dark stormy day I get next to no solar, but on a bright overcast winter day there's almost enough for my minimum use).
The way this works is - the system is programmed to fire up the generator when the batteries fall to 30%, and the generator will run at full load - where it's the most fuel efficient - until the batteries are at about 80%, and then turn off. The vast majority of time, the generator isn't running (blessed silence) as the house uses the battery, and it when it does run you get the most from it as possible (you can also set lock-out time periods where the generator won't run even if the battery is this low, unless it gets to another lower point - for instance I'd set the lock-out from 9pm-6am with a force turn-on at 20%, to keep things quiet at night).
My area gets multiple-days power outages in the summer (because of <10% humidity + decent winds = power line fires) - hopefully less as they update power lines and better maintain the ROW's - and short to medium length outages in the winter (last January, out power went out for a day, but some friends a few miles away lost power for three weeks because of the same storm).
The biggest problem with an automatic transfer switch is that it's going to use up all of your fuel in a hurry. The typical generator is not exactly sipping fuel even at idle, unless you really shell out and get a diesel. The automatic transfer switch will power up that generator at 2AM when the power fails and though you've got 300W draw in the house, you're still using 1/2gph. This is fine, if you've got 250-300 gallons available and you're only expecting to have a couple days failure. A week? It's gone and you're out of power.
For DIY-ish people, my strong suggestion is a manual transfer switch for specific circuits - water well, a couple lights, furnace/heat pump, maybe something else. You connect your generator and run it manually and it will last a long time, because you turn the damn thing off as soon as you don't really have to have power.
We've had that setup, and I ran this place during an extended power outage when there was a (very) nearby forest fire and kept our fridge and deep freeze going, plus intermittent use of the well when we came back, with a 3.5kW generator - it wasn't on all the time; we just ran it occasionally to re-chill the stuff or when we really needed to flush. It's a hassle, but a 3.5kW generator barely uses any fuel this way.
I've put a lot of thought into doing a whole-house genset (and I plan to do it), but my situation is a bit different. I've got solar, plus batteries, and the whole house automatically swaps to battery already in a grid failure.
I can set up a generator as input to this system, so that it can recharge the batteries for winter use. With this, and judicious use of electricity in the house, I figure I can weather a 30-day power grid failure with zero solar recharge, which is really unlikely to happen (on a really dark stormy day I get next to no solar, but on a bright overcast winter day there's almost enough for my minimum use).
The way this works is - the system is programmed to fire up the generator when the batteries fall to 30%, and the generator will run at full load - where it's the most fuel efficient - until the batteries are at about 80%, and then turn off. The vast majority of time, the generator isn't running (blessed silence) as the house uses the battery, and it when it does run you get the most from it as possible (you can also set lock-out time periods where the generator won't run even if the battery is this low, unless it gets to another lower point - for instance I'd set the lock-out from 9pm-6am with a force turn-on at 20%, to keep things quiet at night).
