A power generator is a necessity in remote locations where there is no access to mains power. In addition to charging the battery bank, a power generator is used to power 240V appliances such as air conditioners, microwaves, washing machines and dryers.
Conducting a Needs Analysis
The primary considerations when choosing a generator for your caravan are your power requirements and the length of time you need to power items. If in doubt, overestimate your needs or you’ll run the risk of overloading your generator, a common problem.
Here’s a basic guide:
- Low power consumption up to 1200W: A small power generator is adequate for charging a caravan battery bank plus running a few low-demand appliances like a fridge, LCD TV and DVD player.
- Moderate power consumption 2000W: This is a good starting point for a bigger 240V load, including a small air conditioner, laptop, TV and blender.
- Heavy duty, 3000W and over: If you plan on running a caravan as if you’re on mains power, you’ll need 3000W or more. A large air conditioner will consume up to 2000–2500W alone.
Continuous Power vs Peak Power (Starting Wattage)
Continuous power describes the generator’s true, continuous output. Peak power describes the generator’s absolute peak output for a very short amount of time. Manufacturers prefer to quote the peak figure, so ensure that the generator’s continuous output meets your requirements.
Motor-driven appliances require peak power during start-up. For example, a 1300W air conditioner might actually require a starting wattage of 2500W. Your generator needs to accommodate these brief surges.
How long the generator can run for depends largely on the size of the fuel tank and its fuel efficiency. Quoted run times usually refer to the generator operating at 50 per cent load.
Generator vs Sine-Wave Inverter Generator
A regular generator must run at a constant speed to generate the required output and send unfiltered power directly to the outlet. The frequency of the output fluctuates, with the engine speed making it unsuitable for delicate electronics. Regular generators are cheaper than inverter generators, but due to the size of their alternators they are usually bigger and heavier.
Inverter generators filter the output to deliver smooth power (that’s the sine wave) that won’t damage electronics. They have a smaller form and generally run more quietly than regular generators. They can also increase and reduce output according to demand by varying the engine speed. Watt-for-watt they are generally more expensive.
Each type has advantages and disadvantages:
- 2-stroke: Cheaper, have a better power-to-weight ratio than 4-stroke and they’re lighter. However, they’re noisier, less fuel efficient and less reliable.
- 4-stroke: More robust, run more quietly, produce fewer emissions and are more fuel efficient; however, they’re heavier and don’t have as good a power-to-weight ratio.
- Diesel: Significantly more fuel efficient, higher ignition point makes diesel safer than petrol, higher output and significantly longer maintenance intervals. Best of all you can share fuel with your diesel towing vehicle. The biggest issue with diesel generators is cost – they’re considerably more expensive than petrol models.
Other Features to Look For
Here are some optional features to look out for when selecting a generator:
- Parallel connection: Connect two generators in parallel to double the output.
- Electric start: A one-touch electric starter makes for effortless use.
- Remote start: You don’t even have to leave the caravan.
- Overload cutout: This protects the generator from overheating.
- Fuel gauge: Surprisingly, a fuel gauge isn’t standard on many generators.
Before you run out and snap up a new unit, it’s important to consider the main limitations you’ll face in using a generator. They are:
- Noise pollution: If you’re co-located with other campers, use of a generator may be considered poor etiquette or you may only be allowed to use low-noise generators. However, even a low-noise generator with an output of 50–70dB may be deemed inappropriate.
- Fuel: If you’re planning on extended stays in remote locations, a generator may not be your ideal power source when the nearest service station is hours away. In this situation, a generator is no match for the freedom of having a solar power system for low to medium power requirements.
- Weight: Larger capacity generators can weigh in excess of 30kg – you have limited payload to play with, so weight is a big consideration.
- Size: A typical 2000W portable generator may be similar in size to an esky. However, options for storing a generator are fewer than for an esky, given that a generator is heavy and potentially covered in fuel and oil.
While you’re thinking about power, take a look at how camping generators compare to alternative power sources for your caravan.