Thought I would add a few of my experiences with reliable off grid power, and the reasoning behind it. Some may find this useful.
Straight 240 volt AC power, engine alternator combo is the most used method.
Pros:
Large power availability for running welders and other workshop tools.
Simple, as it conforms to general accepted practice.
Reliable being proven technology
Simple wiring, compatable with all mains appliances
Cons:
Inefficient. Engines are only at peak efficiency when almost fully loaded. most elecricity demand is low and constant.
Constant noise/vibration. Engine speed is high.
Constant wear, long running hours.
No power on demand.... generator must be running.
Unless a standby plant available, no redundancy.... all eggs in one basket. total blackout with breakdown.
If standby plant available, wasted investment when not being used
Relatively expensive, with a one off large initial expense.
This was my first system, it drove me nuts having to start and stop it all the time, and most times it would run so lightly loaded it would carbon up the exhaust and smoke. I did add batteries and alternators as below, but it became a frankenstein with belts/pulleys and wires everywhere, with confusing multiple circuits inside the house and garage.
DC generator, battery bank and inverters.
Cons:
Larger less compact installation
More to go wrong
More expensive plant costs long term..... maybe.... see later
maintenance time higher and slightly more involved
Less peak power available
Pros
Initial startup costs less... the installation can evolve with time and money availability.
True power on demand
Redundancy.... less reliance on one source of power
Little likelihood of complete blackout with major breakdown
Cleaner more "accurate" power, especially with sine wave inverters.
Lower engine stress and noise
Increased engine efficiency, constant and heavy loading
Just to elaborate a few things with this system... my preferred method..
An initial installation of this type requires just the engine, one car/truck alternator, suitable battery, and one inverter. The next phase would be to add a second and third and fourth inverter to have redundancy.... they wont all fail a once. For instance, one inverter could run essentials such as freezers and refrigeration. A second inverter would be dedicated to lighting circuits, a third to electronics, radio/TV etc, another fot the workshop, lights and small power tools.If one inverter fails, another can simply be swapped in/take over.. Inveretrs are cheap now and pretty much a disposable item. Buy cheap ones, none seem to be better than others in this price range, and they WILL fail eventually. In my experience, they will destroy literally dozens of mosfets and the time spent to replace them is just not worth it. Remember too not to have more than one freezer/fridge on the one inverter. If several randomly try to start at the same time, the inverter will be toast.
Next would be to add another alternator to reduce charging times, and to more heavily load the engine. These items are very cheap from scrap dealers , they sell for the scrap value. These are also disposable, and will last between one and two years. Many alternators can be added, increasing redundancy, they each have their own vee belt.... they wont all fail at once.
Increasing the battery capacity by adding more batteries can be done at leisure. A larger bank will allow several days between engine run times. Batteries can be had from scrap dealers, approx 50 percent will be wrongly diagnosed as faulty. Auto batteries will last around 12 months, deep cycle up to 10 years.
Solar panels, hydro and wind systems can be easily be integrated into the system by just running a few wires.
Inverters are not capable of running big loads reliably, this is the major caveat when using this system, but there are clever ways around this. To run my MIG welder for instance, I feed 48 volts from , 4 seriesed 12 volt batteries, straight into the DC filter capacitors s of the welder, and use a 12v tap to supply the electronics and and wire feed control board. With elecrtic motors, say for a lathe, several single phase motors are strapped together, the start windings are disabled in all but one to reduce starting current. Once running, motors draw little current. Use 24 volt systems if possible, the current requirement is half that of 12 volts, increasing inverter reiability. Keep batteries, inverters and alternators close together, dont run long DC cabling. A few teaspoons of mineral oil poured into a flooded cell battery will stop evaporation, reducing battery maintenance time.
All the above allows me to have a "seamless" to use a modern up to date word, off grid system with instant power always. If I head off into town I will run the generator while Im gone. In the summer, the solar panels take over. Its totally reliable with very few breakdowns, and takes very little of my time to keep it working. I usually pick up "bargain" priced batteries and alternators when they appear and they then wait patiently to be used.....