Which is better: solar or generator?

Lots of new Airstream owners want to find ways to extend their camping time while “boondocking,” (off-grid camping, away from electrical hookups). So inevitably the question comes up: which is better, a generator or solar panels?

The answer depends on how you camp and the things you use when you travel. Let's look at the three main options available today.

FUELED GENERATORS

Typical gasoline- or propane-powered generators are ideal for powering high wattage appliances like:

  • air conditioner
  • microwave oven
  • hair dryer
  • toaster oven
  • or anything else that requires over 1,000 watts (generally things with big electric motors or heating elements).

For the air conditioner or microwave your generator will need to be capable of at least 2,000 watts peak output, and often more.

Honda EU 2000

Generators have a few important downsides to consider:

  • The emissions controls implemented on generators are currently weak, and many models (sold outside of California) have no emissions controls at all, so they pollute the air. Operating a new, average portable gasoline generator for 1 hour emits as much smog-forming pollution as driving an average passenger vehicle for about 150 miles. (1
  • They're noisy. Both Yamaha and Honda make excellent products which have good reputations for reliability and quietness, but even those can shatter the tranquility of camping, which brings us to the next downside ...
  • You can't always use them. Campgrounds usually limit "generator hours" to preserve the peace for other campers.
  • Generators are very inefficient at charging batteries. Any RV generator you can buy will produce far more power than the batteries will accept at any given time. Batteries typically take hours to gain a full charge, which means you're wasting a lot of gas waiting for the batteries. Bigger generators can't speed up the process, so they just waste more fuel. 

Generally, we recommend fueled generators to people only when there's no other choice.

CARGENERATOR

This product is a great option if you travel with devices that need to plug in but require less than 1,000 watts, like:

  • laptop computers
  • rechargers for phone, tablet, e-bike, shaver, etc.
  • TV and DVD player
  • portable electric cooler

CarGenerator is basically a high-quality inverter that uses your tow vehicle to power devices like those in the list above, and charge your Airstream's batteries.

CarGenerator pure sine inverter

Just connect CarGenerator to your vehicle (two alligator clips or a handy quick-connect option), plug the Airstream into the CarGenerator, and turn on your vehicle. The Airstream batteries will charge and all the power outlets in the Airstream work, while the truck idles.

The battery charging speed is the same as if you were plugged into campground power. So, if your batteries are nearly fully discharged, you'll probably use the CarGenerator for several hours.

In other words, this product does what a fueled generator does, but it differs in several important ways:

  • Much smaller and lighter than a generator
  • Less expensive than a generator
  • Doesn't require its own fuel (no need to haul gas cans)
  • Maintenance-free
  • It's as quiet as your tow vehicle at idle
  • Pollutes much less than a standalone generator, because any modern vehicle has advanced emissions controls.

The major limitation is that CarGenerator powers devices only up to 1,000 watts. That rules out using the microwave oven and air conditioner.

CarGenerator is ideal for people who want a reliable source of power, and don't like the idea of hauling a generator and fuel can around. We find that customers who have solar panels also like it as a backup, in case of a long spate of cloudy days.

SOLAR PANELS

Solar panels are best when you are primarily interested in re-charging the Airstream's batteries. Solar panels only provide power to charge the batteries. They don’t directly power anything—the batteries do that. For more about solar, read my blog "Solar—simplified!"

For many people solar is the ideal solution, because:

  • Solar panels are silent
  • You don't have to carry fuel
  • They're virtually maintenance free
  • Zero pollution

Solar’s big advantage is in recharging batteries, so if extending your time at camp is your primary goal, solar panels are the preferred option. Rather than pumping out large amounts of power in short time periods like a generator, solar provides a steady all-day charge will have a much better chance of getting your batteries up to 100%. With batteries, slow and steady wins the race.

Solar's disadvantage is that it doesn't charge your batteries on cloudy days, or if the panels are in the shade–such as when you're Airstream is parked under trees. A portable solar system can solve the latter issue because you can place the system's panels in the sun and leave the Airstream parked in the shade.

Portable solar kit

If you're wondering whether to choose a permanent rooftop solar installation or a set of portable panels, check out this blog for more info. 

 

Regardless of whether you choose a fueled generator, a CarGenerator, or solar panels (or a combination of these options), upgrading your Airstream to give you more boondocking time is a great advantage. It will open up new travel options for you and eliminate worries about running out of power when on a long trip.

 

Featured photo credit: Elena Mozhvilo on Unsplash

8 comments

Todd R Brown

Todd R Brown

I wondered if Airstream is considering placing one of the large lithium battery banks used to power the trailer wheels as an option for trailers without the powered wheels. This would eliminate the need for the batteries carried on the tow frame and extend boondocking time.

Jeff

Jeff

Refrigerators… the new ones supposedly use less amps. Do the news ones fit into the <1000W? The older propane-electric refrigerators aren’t as efficient. Do they fit into <1000W’s or will we need a generator for long e-untethered camping?

Jim MacDonald

Jim MacDonald

Hi Rich, above you stated that generators, like the pictured Honda i2200EU, have no emission controls. That is incorrect. As far back as 1990 the California Air Resources Board began requiring exhaust emission controls on small off-road engines. Honda’s owners manual refers to their engines emission systems. CARB regulates evaporative emissions as well as CO, NO2, and particulates. I assume that Honda sells the same engine in all 50 states unlike passenger cars, it’s just too small a market to differentiate states I’d guess? But you are correct to state that passenger car engines have much lower exhaust emissions.

Peggy

Peggy

It seems like the CarGenerator would have a disadvantage in having to keep your vehicle at idle for long periods of time.

Barry Connors

Barry Connors

Great article.
Although you mentioned clouds and shade the region of the country is an important factor. For example, It would be difficult to find a sunny camp location in the northeast, Alaska or the Smokey Mountains of North Carolina.

Rich Luhr

Rich Luhr

Hi Jim
Thanks for your additional info. I’ve amended my blog to be clearer on this point.

It is true that CARB has implemented some standards but have historically been pretty weak and don’t compare to the emissions controls on modern cars. From their web page: “Despite their small size, these engines are highly polluting. The volume of smog-forming emissions from this type of equipment has surpassed emissions from light-duty passenger cars and is projected to be nearly twice those of passenger cars by 2031.”

New, and much better standards will take effect with the 2024 model year, but pretty much every generator made up to now is a big polluter, even those that are “CARB compliant”. And, generators not marked “CARB compliant” still may have no emissions controls at all.

Rich Luhr

Rich Luhr

Peggy, it’s not a problem for modern cars to idle. It’s doesn’t hurt the vehicle, and the length of time they would need to idle is the same amount of time you’d need to run a generator—with the advantage that the vehicle produces fewer emissions.

Rich Luhr

Rich Luhr

Jeff, it’s true that the new compressor-type electric refrigerators are efficient but they use a lot more electricity compared to propane refrigerators, and that’s why people are having problems running out of power.

They typically draw anywhere from 2.5 to 6 amps, which is 31 to 75 watts, well within the 1,000 watt capability of a CarGenerator.

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