Prepared Society Forum banner
1 - 9 of 9 Posts

· Registered
696 Posts
Common generators will come in three different drive types,

1. Combustion engine, Burning fuel in an engine to turn the generator.
(gasoline, diesel, LPG, CNG, Alcohol, ect.)

2. Wind Turbine. Wind power working to turn your generator.
There are several different kinds of theses.

3. Water Power. What we call 'Micro Hydro', or a very small water powered turbine turning your generator.

There are a few others, but they are as yet, fairly undeveloped...

Then you must decide what you want your generator to produce,

AC, or Alternating Current, what the electric companies supply to your house right now, and depending on where you live the standard might be 96 Volts AC to 250 Volts AC.

DC or Direct Current, like your car battery stores and your car alternator produces.
These DC systems are usually in some standard configuration, 6 Volts, 12 Volts, 24 Volts, 36 Volts or 48 Volts.
Most are based on using 6 or 12 volt batteries to store the excess current for later use.

So, once you decide what energy source you want to use to power your generator,
And what output form you want the generator to supply, we can narrow things down further for you...

Most people go with gasoline, diesel, LPG or CNG to power the generator,
And go with household current, 110 Volt AC output in the US since that is our standard, and they can run essential items directly off the generator.

· ke4sky
190 Posts
Generators 101

Portable Generator Basics And Safety

If you can't recharge your batteries when the grid is down, once you have run them down, they are useless. Generators are a good solution, but are not the only answer.

If you don't know what you are doing, stay away from generators, because a screw up may kill you!

NEVER connect a portable generator to house wiring unless a double-pole, double-throw transfer switch has been hard-wired into the breaker panel.
This disconnects the house wiring from the AC mains.This prevents your generator from injuring utility personnel working trying to restore your power and also prevents "back-feed" from blowing up your equiopment when the mains do come back up. Installing a transfer switch requires an electrical permit and inspection and is a job for a licensed electrician which must meet requirements of the National Electrical Code (NEC).

An adequate earth ground is needed for any portable generator.
This is necessary to ensure your personal safety. Never run a generator in standing water or work on the generator or feed lines while standing on wet ground.

Never run a generator inside an enclosed building
This is because it is impossible to adequately ventilate carbon monoxide and fumes.

Use only UL-listed 3-wire extension cords.
Always plug cords into equipment first before connecting them to the generator feed. Medical devices and computers require clean "sine wave" 60-cycle AC power and should never be run direct from unconditioned "square wave" generator feeds of varying cyclic rate.

Gasoline generators produce about 600w at 120 volts AC for each engine horsepower.
A 100-watt HF-SSB transceiver requires about 1200 AC watts at 120 volts. Generator capacity must be sized to not only the running wattages of the equipment, but also for the starting loads. For low-loads such as furnace fans multiply running wattages x 2, for pumps or compressors you must multiply the running wattages x 7.

A 3.5 HP portable generator is the minimum recommended to operate a home emergency radio station for ACS or RACES use. It can be carried by one person, uses 5 gallons of gas every 24 hours and produces about 2 kW. It can power a modest station, such as a 100w-SSB or VHF-FM Landmobile or amateur radio, laptop PC, wireless modem or terminal node controller, several small NiCd chargers, an automotive battery charger and limited emergency lighting for the radio operatiuong position only. Don't expect 2kw generator to also power your well pump, refrigerator, hot plate and coffee pot!

Light-duty recreational generators are not rated for continuous duty, They may "quit" and not restart when hot, under prolonged disaster conditions. They should be limited to intermittent use for battery chargers, emergency lighting, cooking and limited use of power tools.

The minimum generator to power an average single-family house or an Incident Command Post in the field supporting a SAR or wildfire supression mission is 5kW. A typical commercial-grade, continuous-duty generator of this size has an 8HP engine, weighs 200 lbs., produces 32A at 120 volts and runs 8 to 10 hours on 5 gallons of gas and requires a 55-gal drum of clean fuel to be brought ot it every 72 hours of continous duty at full load. A larger generator is practical only if you have a reliable source of fuel.

It is unsafe to store more than one 5 gallon jerican can of gasoline in your barn or garden shed. F-3201.2 of the Uniform Fire Code prohibits storage of more than 5 gallons of gasoline in residential areas. Storing larger quantities in a residential area requires a hazardous use permit and storage area which meets the NFPA standard. Stored gasoline goes bad in a few months unless treated with stabilizer.

Store extra gas cans empty. When the hurricane Watch changes to a Warning, then fill your cans while there is still mains power to run the pumps, then store them under cover, and securely tied down outside! Once the generator is started, use a wooden dip-stick to check fuel level every 2 hours and top off tanks before they run out.

Generator Safety Tips From the U.S. Consumer Product Safety Commission:

Carbon monoxide hazard!
Never use indoors or in attached garages!
Set up OUTDOORS in a well ventilated, dry area
Away from HVAC air intakes
Under a canopy, open shed or carport

Electrocution Hazard!
Adequate grounding of generator and equipment!
DO NOT connect or plug into household AC!
Plug only individual devices into generator
UL-rated cords of wire gage adequate for load

Explosion / fire hazard!
Fuel vapors can travel along the ground and be ignited by sparks, arcs from switching equipment, or pilot lights from appliances!
Store fuel outdoors in a ventilated shed
Use Fire Marshall approved containers

If a backup generator is to be connected to a building electrical service, NEC requires that it be equipped with a double-pole, double throw transfer switch.

· Registered
696 Posts
Getting ahead of things if the guy doesn't know what system he wants to use yet...

· Registered
160 Posts
What do the turbines have so that they won't get clogged up by water debris floating around?
There is a very similar thread already started...

It links to a website that talks about mini-hydro electric generation.

Take a drive out to a hydro electric station. The smaller (and more remote), the better. Things tend to be easier to see. There are grates to catch large debris (logs, sticks, etc), and they design the systems to handle anything below a certain size. The smaller the turbine, the finer your filtering needs to be.

· Registered
696 Posts
What do the turbines have so that they won't get clogged up by water debris floating around?
It's called a 'Trap' or 'Grated Inlet'.
Where the water runs into your 'Collection Head' or 'PenStock', you simply install a slanted grate over the inlet, and that will angle most of the debris off the top of your collection box...
You build a small dam/retainer wall in the water stream, and collect your water from about 1' from the bottom of the standing pool.

This won't solve all your problems, you will eventually have to clean out your generator turbine at some point, but it will greatly reduce the amount of crap that can reach the generator.

You will start out with a 'Collection Head' or 'PenStock', then the water will follow a pipe down hill.
The amount of drop from the collection head to your generator and amount of water (Size of pipe, Amount of water in it) will determine how much energy you can make.

A stream about the size of a healthy garden hose will turn a car alternator size generator, and those can be super cheap & simple to put together.

I'm not saying you can use a car alternator right off a car for this!
You CAN rewind a car alternator, add permanent magnets, and make a nice Micro-Hydro generator...
If you have a larger water supply, around a 3" line with good "Fall" so it builds up a lot of energy, you CAN turn a car alternator, although that isn't the most effective way to generate electricity.

I've seen generators made from car alternators mounted in 5 gallon buckets make perfectly good current,
I've seen tethered floating docks with 55 gallon drums cut in halves making up a paddle wheel in the center of that dock turning generators that lit up community centers and pumped water from clean wells in the Jungles of Central and South America.

It just depends on what you have for parts and what you can do with them...
I have a friend with a VERY SMALL creek flowing through his place, He's got a 'Squirrel Cage' thing hooked up to a permanent magnet motor and it looks like crap, but works just fine!

The 'PenStock' is the water collection and intake point, and you will need to use some sort of strainer there to keep the crap out.

The more water you can capture, and the farther it falls, the more energy it will deliver to your generator....

Interested in generator designs? If so, let me know and I'll try to find a few pictures and explanations.
1 - 9 of 9 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.