Help with idea on alternator and inverter

[Kawak]

Hi all

My old 6.5kva generator just quit working during load shedding, serviced a year ago, so sick of these things that I need to service and doesn't last long. An idea came, can I just oversize an alternator on a car, use an inverter on that, hookup massive battery chargers on charge my battery bank and run part of the home from that?

The idea is to move off grid eventually and then still have the car as a backup genie when the weather acts up.

Anyone know an auto electrician that can fit an oversized alternator? Any reason why I shouldn't do this? Engine wear or fuel economy issues with a larger alternator?

Thanks

 

[WAslayer]

What in the actual hell did I just read..

Seems like much less effort, danger, smarter to just buy something like this:

2400VA Mecer Inverter + 2x 100AH Batteries Trolley (8 HOUR BATTERY LIFE) KIT - 1440W (150-200 cycles) - GeeWiz

2400VA Mecer Inverter + 2x 100AH Batteries Trolley (8 HOUR BATTERY LIFE) KIT - 1440W (150-200 cycles) for sale online at the Best Prices! Door to Door and Overnight Delivery

www.geewiz.co.za

 

[Lupus]

Hi all

My old 6.5kva generator just quit working during load shedding, serviced a year ago, so sick of these things that I need to service and doesn't last long. An idea came, can I just oversize an alternator on a car, use an inverter on that, hookup massive battery chargers on charge my battery bank and run part of the home from that?

The idea is to move off grid eventually and then still have the car as a backup genie when the weather acts up.

Anyone know an auto electrician that can fit an oversized alternator? Any reason why I shouldn't do this? Engine wear or fuel economy issues with a larger alternator?

Thanks

No you can't just oversize an alternator. A car engine doesn't put nearly enough power to actually be usable.

 

[Geoff.D]

Hi all

My old 6.5kva generator just quit working during load shedding, serviced a year ago, so sick of these things that I need to service and doesn't last long. An idea came, can I just oversize an alternator on a car, use an inverter on that, hookup massive battery chargers on charge my battery bank and run part of the home from that?

The idea is to move off grid eventually and then still have the car as a backup genie when the weather acts up.

Anyone know an auto electrician that can fit an oversized alternator? Any reason why I shouldn't do this? Engine wear or fuel economy issues with a larger alternator?

Thanks

A cousin of mine used a VW beetle engine on a block, to run a ring of generators with a fancy belt system charging a bank of 12volt batteries in the 1970's. Worked like a charm.
But frankly, there are much better ways to skin this cat now.
If you stick with the genie route then forget all toys and buy a real one from a high end supplier.

6.5 kVA is far too small for continued use as a back up. At least 10 kVA is required.

 

[ScottulusMaximus]

Hi all

My old 6.5kva generator just quit working during load shedding, serviced a year ago, so sick of these things that I need to service and doesn't last long. An idea came, can I just oversize an alternator on a car, use an inverter on that, hookup massive battery chargers on charge my battery bank and run part of the home from that?

The idea is to move off grid eventually and then still have the car as a backup genie when the weather acts up.

Anyone know an auto electrician that can fit an oversized alternator? Any reason why I shouldn't do this? Engine wear or fuel economy issues with a larger alternator?

Thanks

No

 

[Alton Turner Blackwood]

An alternator outputs AC.

I think you need to first get the basics of electricity right.

 

[Kawak]

What in the actual hell did I just read..

Seems like much less effort, danger, smarter to just buy something like this:

2400VA Mecer Inverter + 2x 100AH Batteries Trolley (8 HOUR BATTERY LIFE) KIT - 1440W (150-200 cycles) - GeeWiz

2400VA Mecer Inverter + 2x 100AH Batteries Trolley (8 HOUR BATTERY LIFE) KIT - 1440W (150-200 cycles) for sale online at the Best Prices! Door to Door and Overnight Delivery

www.geewiz.co.za

Already have an axpert inverter with lithium backing up all lights, and entertainment systems.

Need a genie for cooking and fridges when the load shedding gets bad and when the power stays off for days, had a few of those in the past, Ekurhuleni is not to be trusted.

 

[Kawak]

No you can't just oversize an alternator. A car engine doesn't put nearly enough power to actually be usable.

Car engines have way more capacity than the ones on genies, also, many have larger alternators fitted for their upscaled entertainment systems in their cars.

 

[Kawak]

An alternator outputs AC.

I think you need to first get the basics of electricity right.

But cars provide 12vdc, alternators are also rated at around 13.5v, I would like 52v to charge my battery bank but that doesn't seem to matter as I just want to cut out having another ICE to maintain.

 

[Rickster]

An alternator outputs AC.

I think you need to first get the basics of electricity right.

They have a diode in them to convert AC to DC.

How can you charge a battery with AC, cmon man.

 

[Geoff.D]

But cars provide 12vdc, alternators are also rated at around 13.5v, I would like 52v to charge my battery bank but that doesn't seem to matter as I just want to cut out having another ICE to maintain.

By replacing one ICE with another on wheels?
No man really think this through.
6.5 kVA is suitable for a few lights and to run a TV ETC. That is it. Not for water heating cooking and serious battery charging.
What was the duty cycle rating on your genie?
Bet you were exceeding that by a few 100 % regularly.

 

[WAslayer]

Already have an axpert inverter with lithium backing up all lights, and entertainment systems.

Need a genie for cooking and fridges when the load shedding gets bad and when the power stays off for days, had a few of those in the past, Ekurhuleni is not to be trusted.

Just get a generator meant for long term and more heavy duty use then:

MAC AFRIC 20kVA (16KW-230V) Silent Diesel Generator with ATS (powered by FAWDE diesel engine) - Adendorff Machinery Mart

The ultimate home generator is now available at Adendorff! With 16KW of Diesel power created by a world-renowned FAW engine – you can live your life uncompromised whether there’s power from the grid or not. If you are worried about noise, you can rest assured that your sleep will remain...

www.adendorff.co.za

By the time, assuming it will even work, you have finished this pipe dream, you would have likely spent enough to buy the above generator anyway..

 

[TheChamp]

If you no longer want the car you can use the engine and connect it to the motor from your generator, that's pretty much what the industrial generators are, a truck engine connected to a massive motor, we have a Scania and a Mitsubishi at work.

I doubt it will be efficient with a petrol engine but it would be a cool project nonetheless, I have always wanted to do one of those.

 

[Kawak]

Really wanted to just clip in a 12v pure sine inverter into my car battery, rig everything from there, not a mechanical engineer, has no idea how to service any engine, but thinks this is such a missed opportunity, the pain of loading the genie onto my bakkie just to get a service done on it, bladdy thing is 120kg, @WAslayer and his genie idea will be completely impossible to move, @Geoff.D maybe I was pushing the genie, which I thought was big for home use, over the limit, it is over 15 years old, though I don't use it much since it only gets turned on when I cook.

Considering where to go, service this old genie again, a new, more portable genie which I may use more in the future once off grid? A humongous generator? It's really difficult to find mechanics that are willing to come out and do an onsite service.

What are your thoughts.

 

[Kawak]

If you no longer want the car you can use the engine and connect it to the motor from your generator, that's pretty much what the industrial generators are, a truck engine connected to a massive motor, we have a Scania and a Mitsubishi at work.

I doubt it will be efficient with a petrol engine but it would be a cool project nonetheless, I have always wanted to do one of those.

Point was to have the old car retain car status, I need to be able to drive it to be serviced. Can't say I know how to check a spark plug, never mind changing it.

Your project idea sounds great though, consider that a 10kva generator has an engine just shy of 500cc, any 1600 engine can pull 30kva, some kick ass generator

 

[Lupus]

Car engines have way more capacity than the ones on genies, also, many have larger alternators fitted for their upscaled entertainment systems in their cars.

No a cars motor doesn't have way more capacity then a generator, unless you're referring to the tank.
Firstly you would need to run the cars engine flat out all the time for it to be reaching its peak kw.
You'll end up spending a lot on petrol and possible damaging your engine. Save up and buy an inverter with some batteries rather.

 

[Lupus]

By replacing one ICE with another on wheels?
No man really think this through.
6.5 kVA is suitable for a few lights and to run a TV ETC. That is it. Not for water heating cooking and serious battery charging.
What was the duty cycle rating on your genie?
Bet you were exceeding that by a few 100 % regularly.

Actually 6.5kva can run a lot more then a few lights and a TV. This isn't the old days where lights were 60w for the lowest wattage. 6.5kva can run most houses, minus the geyser and stove. Think about it a lot of people are running their houses on 5kw inverters nowadays.

 

[Lupus]

Point was to have the old car retain car status, I need to be able to drive it to be serviced. Can't say I know how to check a spark plug, never mind changing it.

Your project idea sounds great though, consider that a 10kva generator has an engine just shy of 500cc, any 1600 engine can pull 30kva, some kick ass generator

That's not how it works, you don't just take the capacity and multiple it. You're car engine doesn't always output its maximum potential, if you want it to you're going to be running it flat out, which isn't good for a cars motor. You've already popped a generator by running it flat out.
Now you want a more costly motor to pop? Invest in gas for cooking it'll be way cheaper.

 

[Tinuva]

Can't fault this guy for trying to think of the box.

Why not buy a trailer and permanently mount the gennie on there. Easy then to take it for a service.

Or... Learn how to service it yourself.

 

[Geoff.D]

Really wanted to just clip in a 12v pure sine inverter into my car battery, rig everything from there, not a mechanical engineer, has no idea how to service any engine, but thinks this is such a missed opportunity, the pain of loading the genie onto my bakkie just to get a service done on it, bladdy thing is 120kg, @WAslayer and his genie idea will be completely impossible to move, @Geoff.D maybe I was pushing the genie, which I thought was big for home use, over the limit, it is over 15 years old, though I don't use it much since it only gets turned on when I cook.

Considering where to go, service this old genie again, a new, more portable genie which I may use more in the future once off grid? A humongous generator? It's really difficult to find mechanics that are willing to come out and do an onsite service.

What are your thoughts.

1. There is no such thing as a simple solution to high power requirements needed for water heating or cooking.
2. No way will you get anything that you can simply connect to a car battery and used to provide power to an electric stove or geyser.
3. Below 10kVA is generally for relatively short term backup for most small appliances up into say a kettle or an electric iron, but both of these are pushing the envelope.
4. Even using one of these for a fridge or freezer is pushing your luck. Washing machines, especially ones with heater elements, driers are all on the no no list IF used for long periods on a small genie and in combination with other devices.

As @WAslayer has suggested, you need to go to a proper supplier, who will then suggest diesel, on a trailer if you also want mobility.
At least 10kVA or bigger with a high duty cycle.

What is the existing plant? What make?
You have two choices, get it fixed and then only use it within its capability or sell it as is.
Longer term is to go gas for cooking and prob hybrid solar for heating water.