What kind of generator do I need? – Part 2

Now that we know if we need a generator and roughly what size, let’s find out what kinds of generators are out there and their pros and cons.

Gasoline units dominate the industry and they are good IF they are what you can use most effectively. You can buy them almost anywhere, Home Depot, Lowes’, ONAN, Generac and Honda dealers, your local ACE Hardware or big box store, and the always popular Internet. What’s best? – It depends (you’re gonna hear that a lot).

If you boondock or camp far away from other people, you can get away with a ‘contractors grade’ unit. This is an air cooled, 3600 rpm, NOISY, NOISY, portable generator that you store in the back of the truck and unload at the campsite along with a couple of 5 gallon jugs of gas. If you’re not using it for camping, you can use it at home in case of a power failure. It will run the fridge, freezer, TV, some lights, etc. The use of these generators in a campground is a very good way to meet the neighbors and/or the campground hosts or the park rangers. There has been some talk of filling sandbags and building machine gun nests to help get rid of these little noisemakers. Most people go camping to get closer to nature and the contractor level generators sort of destroy that capability. Be considerate of the neighbors, they may get to pick the jail you’ll be placed in.

There are some small portable units out that are specifically designed for us campers. They are lightweight for their power output and some feature variable speed engines with quiet mufflers and electronically controlled power output. A few can be connected together to provide a larger power output.

The built in gasoline generators usually start at 2800 watts and go to 7000 watts. They range from one cylinder, air cooled, 3600 rpm, big muffler and sound deadening covers thru some liquid cooled 4000 and 6000 watt models and further up to the 7000 watt, 2 cylinder, air cooled, 2300/3600 rpm belt drive, with at least one model having fuel injection instead of a carburetor.

Gaseous fuel units. This is a fancy name for liquid or low pressure gas propane engines driving generators. For the most part, the engines are identical to the gasoline ones except for the fuel system. However, there is not as much power (BTU’s) in propane as in gasoline. Therefore, a propane unit, although identical to a gasoline unit will produce less power. An example is the ONAN KY series. With a gasoline fuel system it outputs 4000 watts, with propane only 3600 watts. While this seems to be a detriment, propane burns much more cleanly than gasoline. You can also store propane for a much longer time than gasoline. All in all, a propane unit will burn slightly more fuel, but have less maintenance costs than a gasoline unit. So, if you primarily run the generator at the rest stop when traveling between campgrounds, propane might be your best bet. Low pressure vapor withdrawal usually uses the same regulator as the rest of the camper. If the regulator is too small for the complete system, or the temperature drops near or below freezing, the system pressure may fall below minimums. Liquid withdrawal is probably best for low temperatures or long fuel line runs but propane will precipitate a heavy oil at the point of vaporization that could plug the regulator unless it is drained periodically (once a year or so). High pressure vapor takes fuel vapor from the top of the propane tank and directs it to the same components as liquid withdrawal. It does not have the oil deposition problems that liquid withdrawal has. Gaseous fueled units usually start at the 2800 watt point and go to 7000 watts in RV level units. They are not really designed to be portable due to the fuel tanks involved.

Diesel units are predominately in motor homes and maybe in the very large campers. Diesel fuel has more btu’s per gallon than gasoline or propane and stores better than gasoline. They have more power for a given engine size. One drawback is that diesel engines are very susceptible to air or water in the fuel. Diesel units start around 5000 watt and run upwards to as large as you need/want or can fit in the motor home.

Generator Jim