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Maximum Fuel Efficiency and Power Storage

Maximum Fuel Efficiency and Power Storage

RE: Maximum Fuel Efficiency and Power Storage

Wnat on earth are you trying to accomplish at the end of the day by having so many energy conversions and why are you using a relatively-poor-efficiency gasoline generator as a power source and why are you proposing a storage medium that contains such a trivially small amount of storage?

If you're trying to supply power to your campsite and your load is that small, buy a smaller generator and forget about storage.

If you're trying to supply power to your campsite and your load is intermittent and you want to save fuel while the load is switched off, buy an inverter generator (lets the engine speed be independent of the AC frequency) and forget about storage. (I have a Yamaha EF2000i inverter generator that I use at the race track for exactly this purpose. Off the shelf ... no shenanigans ... warranty ... starts one pull every time ... no hassles no headaches)

If you're trying to supply power to your house off-grid, you need a much more efficient energy source, probably tied to a bank of batteries, feeding an AC inverter to the household 60Hz AC loads.

If slowing the generator down isn't enough and you really want to switch it completely off, you need a much more serious energy storage system.

If this is a back-up generator for emergency use only as a substitite for when your windmill and solar aren't generating enough, see above; just have the generator charge the batteries when it's running and switch it off when they're full.

The amount of potential energy stored in your grandfather clock is trivial and insignificant compared to what you actually need.

What am I missing by attempting to be completely practical here, by using bits and pieces that you can actually get on the marketplace and are adequate for the task and are proven to work?

RE: Maximum Fuel Efficiency and Power Storage

Investigate invertor generators.
They generate DC which is then inverted into AC. When less than the maximum power is required they throttle the engine back to a slower speed. By the time you add up all the losses and account for the ineficiencies of your proposed storage system, an invertor generator may be competetive. Do your own research as to fuel consumption under light loads for various brands. There may be differences.

Quote (BrianPetersen)

If this is a back-up generator for emergency use only as a substitite for when your windmill and solar aren't generating enough, see above; just have the generator charge the batteries when it's running and switch it off when they're full.
This is also a good solution. This can be automated with battery voltage monitoring, load monitoring and automatic generator starting.
Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Maximum Fuel Efficiency and Power Storage

That's a rather sketchy proposal. It would likely get A+ marks from the greenies who have no clue about the reality of such things, because in reality it wouldn't work worth a damn for anything useful.

Without any losses, 1000lbs at 30ft stores enough energy to light a 60W light bulb for 11 minutes or it would power 1200W of load (your generator rating) for 67 seconds. You might be able to recover 60% of the stored energy so expect close to 1/2 of those run times.

Then, I have no idea how you expect to recovery any energy from that hoist or how a computer will reliably start a generator without a starter motor and with a manually operated choke.

RE: Maximum Fuel Efficiency and Power Storage

Like free energy, these storing energy in weights ideas never die. No one has ever produced one that works. I live several months of the year off grid with only about 1KW of solar and a car battery. The excess PV makes the hot water. A small generator operates the laundry.

RE: Maximum Fuel Efficiency and Power Storage

Well, there are some storage systems using water as the weight successfully. But I don't know of any systems using solid weight blocks.

RE: Maximum Fuel Efficiency and Power Storage

There is definitely scope for using rotating mass as a power storage method, this is found in such applications as remote area diesel powered plant, and for rotating UPS equipment, such as that produced by Piller. However, most of that applicability is in terms of power storage (not really an energy storage application per se), rather its there to manage transients and allow for less equipment running at once. The efficiency gain is often realised through integration of renewable energy without having to run additional rotating machines in case of intermittent output reduction from the renewable source, rather than to specifically manage the diesel loading.

However, with the scale and manner of equipment indicated, this particular application looks like a wombat.

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