Is a generator to supply 'almost' all the power worth it?

[Atila Iskander]

When you consider that you do NOT need to keep appliance like refrigerators & freezers powered 24/7, and that a bit of judicious shifting can save your time & fuel, the size equation changes. The only thing I would run during the day would be heat or A/c with some refrigerator to compensate for regular heat loss.

So in effect my base use is Heat or A/C At the cabin ADD well pump Add to that ONE OF Fridge, freezer , (Cabin) Hot water heater. In the morning and evening, turn off Heat or A/C run Hot water heater and well pump, while doing morning and evening shower & bathroom stuff And that pretty well covers things

If you get an inverter equipped generator you can save some fuel because it will adjust output to demand This is not an issue for occasional / emergency generators But it can be a saving for generators that are for extended use.

[trader4]

All generator adjust output to demand. And all use a lot more fuel when fully loaded than with a light load. I think what you really mean is that with an inverter type the engine speed can vary which does save some fuel.

However the inverter type ones I've seen were all fairly small, not in the class of one to function as a whole house unit.

[jamesgangnc]

the power to your home? like 10kW or 20kW. and if so, which one and how mu= ch? Or just stick with a 2kW, or so and time multiplex each operation - a l= ittle fridge time, a little heater time, a little well pump time, etc.

In my opinion, not. Just running bigger generators uses up a fair bit of g= as because most have to run at a specific rpm to deliver the correct voltag= e and hertz.

I suggest something around 4k and then you can pretty much run anything in = your house simultaniously except for ac compressors and things that use ele= ctric resistive heat.

[trader4]

ll the power to your home? like 10kW or 20kW. and if so, which one and how = much? Or just stick with a 2kW, or so and time multiplex each operation - a= little fridge time, a little heater time, a little well pump time, etc.

of gas because most have to run at a specific rpm to deliver the correct vo= ltage and hertz.

RPM isn't the main determinant of fuel usage. Load is. Watch the governor/throttle linkage on a generator, mower, etc as the load changes.

How much more a larger generator uses when running a smaller load vs a smaller generator that is fully loaded has been debated. Evidence was presented that it depends on the generators, type of fuel, etc. It can vary from very little difference to a more substantial one. Best thing to do is look at the specs.

[HeyBub]

Here's another thought: If there is no emergency, an itty-bitty 900 watt generator and a 210kw whole-neighborhood one use exactly the same resources. They only differ in how much they cost.

[Smarty]

the power to your home? like 10kW or 20kW. and if so, which one and how much? Or just stick with a 2kW, or so and time multiplex each operation - a little fridge time, a little heater time, a little well pump time, etc.

because most have to run at a specific rpm to deliver the correct voltage and hertz.

I will add the observation that the life expectancy of the engine should be a consideration also, since the smaller generators such as the Generac and Guardian 6/7KW use a single cylinder engine whereas the larger units all use a 2 cylinder engine with significant differences in the choice of materials for the block, the head, the carbs, the type and location of valves, etc.

Finding the actual reliability data (like MTBF, MTTR, failure modes, etc.) is a tricky business, but at least one web site I am aware of which specializes in Generac repairs has quite a bit of anecdotal information. It is worth reading it carefully if you happen to chose Generac or Guardian brand equipment and want to know which models seem to survive with the least amount of hassles and problems.

It has been extremely helpful to me as I have been advising and helping others making purchase and installation decisions over the last 5 years. The forum is heavily frequented by very knowledgeable people, and also contains a dealer rating service for those who want to leave the installation to "experts".

Here is the link:

Hope this helps you and others,

Smarty