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Can I build an Emergency generator?

I have an old 30hp brushcutter motor (Einhell SBC) with square drive. Can I use this to build an 230V AC emergency generator and, if so, what would I need in the way of an alternator.

Get a 12000 watt 230 volt AC generator and connect it to the motor.

Get a 10, 100 amp, 12 volt, alternators and inverter up.

Get 10 50 amp 24 volt alternators and connect them in series then put them through a big sine wave oscillator.
Old codger (author)  Josehf Murchison10 months ago
Thanks for all the replies gents. I was wondering why everyone has been talking BIG stuff then I went back through my original and spotted the "deliberate" mistake. The brush cutter is 30cc - not 30hp!!! I think that this should make a slight difference to the solutions offered - Sorry folks. Must get this brain sorted out sometime.
The output is given as 0.8kw or 1.1bhp
That is really small you could only run a 40 amp 12 volt alternator and a 400 watt inverter but it is doable.

Just wire up the alternator up the same way you would if it was in a car and add the inverter.

I paid 25 for this Inverter.

http://www.instructables.com/id/OFF-THE-GRID/step5/400-WATT-INVERTER/

You can use a larger inverter as long as you run whatever you want off the inverter for short periods and let the alternator charge up the battery while what you are running is idol.
Vyger10 months ago
Back in the really old days they adapted all kinds of things for country use. I remember seeing a set up that used a car (newer than a Model T but not by much). The rear axle was on supports so the wheels were well off the ground and they had a big belt around the tire that connected it to a generator. They did a lot with those really long belts back then. So, you start out in low and shift up to the right speed and the generator powers the house. They also used similar setups for irrigation.They put a big flywheel on the tractor and ran a belt off of it to power the water pumps. Manufacturers saw what these people were doing to solve these problems and started building in things like a PTO into their equipment so people could take advantage of the horsepower. Depending on your setup you might consider using a belt drive to connect up the generator to the engine. And you might be able to find an old generator set up just for that in a junk yard or some similar place.
Old codger (author) 10 months ago
Thanks Rick. I am in France and can get welding done. What spec generator would I be looking for? Maybe An old car genny?
The brushcutter is Kaput and it seems a waste to throw a good engine away. We are in teh country so I thought that a genny to run the fridge/freezer for a while in teh event of a power cut could be handy.
http://www.instructables.com/id/50-CYCLE-GENERATOR/

May give you some idea.

Your going to want something that will provide around 2000 watts to be useful.

A car genny will only give you 12 volts which isn't very useful - although you could run it through an inverter.

Here in the UK you can buy a 2500 watt generator for £170 in Liddles. have a look around.

blkhawk Old codger10 months ago
You need to reply to the member's comment so they are informed of your reply. There is an instructable for a homemade power generator.
rickharris10 months ago
mmmm I guess the answer in principle is yes you could.

Can you weld

Do you have a suitable 110v generator (assuming USA)

If the answer to the above is yes then your in a good place to do this.

Attach the motor and genny with a suitable coupling and wire up a panel with a suitable socket on it. That's really all there is. the hard work should happen in the generator if you buy the right one.

HOWEVER

Your not going to run your entire house off it. 2KVA is pretty typical for a small generator. You possibly consume around 8 kilowatt hours of electricity a day.

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