Does Altitude Affect Generators Performance? Unfortunately, Yes.

Think you got a strong enough generator for the big camping trip? Well, if you headed to any type of elevation, read up and learn: Does altitude affect generators.

How does altitude affect generators? Well, prior to my last camping trip I would have said it doesn’t. But as I (and many others) have learned the hard way is not only does it affect it, it can mean the difference between having power and NOT having power.

Last month, my family and I had an epic Southwest US Mountain Biking trip. We packed up and headed out for 13 days in the truck pulling a 23ft Toy Hauler. In those 13 days, we hit Nevada, California, Arizona, Utah, and back home to Colorado.

Summer was quickly approaching and we knew we planned to boondock off-grid and be self-sufficient (with the exception of a night or two at a campground to re-organize). We decided a week prior to buying a gasoline generator that could power the RV’s 13,500 BTU Dometic air conditioning unit.

Understand How Much Wattage You Need With A Generator

After some research, I determined we needed at least a 3000-Watt Generator as the A/C only needed about 13.8 running amps. Stopped by my local Lowes and picked up the Craftsman 3000-Watt Gasoline Portable Generator.

This was small, easy to move around, and had the power we needed. As soon as I got it home I filled it with oil and gas and fired it up, one pull start! I hooked it up to the RV and just as I planned, it started right up. I let it run for an hour or so and felt good about the purchase and our upcoming adventure.

Once we hit the road, there was no turning back. We traveled about 5 hours north and camped in Wyoming the first night. Fortunately, Wyoming always has chilly nights and no A/C was needed. Once we arrived in Moab, UT, the weather was HOT. We knew immediately we needed A/C. I fired up the generator with no issues and hooked it up to the RV. A/C fired right up and we began to set up our camp area. About 10 minutes into running, I hear the A/C turn off but the generator is still running.

I glance over at the generator and see a red flashing light indicating the generator was being “overloaded”. Confused by this, I checked and rechecked all my connections, fluid levels, and all looked good. So I fired it up and yep, it was overloaded again.

Now, 2 pm in the Moab desert isn’t where you want to be when you find out that you’re not getting A/C when you sleep. I frantically bust out the owner’s manual and start flipping to anything that will help me understand what’s going on. I come across an advisory section that states “For every 1000ft above sea level, the generator loses 3.5% of its power”.

Generators Performance At High Elevation

Well, I’m sitting at about 7-8,000 ft, so for us, that is about 26% of power loss! Additionally, the manual states that ‘For every 10 degrees Fahrenheit over 70 degrees it loses another 1%. So in this case, between elevation and temperature, we had lost 30% of the generator’s power, effectively removing all of the additional power we had when we purchased this unit, forcing it to be overloaded any time we ran the A/C.

What a bummer. Further research into this, I learned that many generator companies make an “altitude jet kit” that will allow more gas into the carb/injection and help account for that loss of oxygen in the higher elevation areas. I should have done more research in advance, but if you are just starting out, here is a good resource to read up.

This is the point in the blog where I normally upload pictures of the Generator on our epic trip, however, I didn’t take any, in fact, the only thing took was the generator back to Lowes for a refund. When it’s all said and done, it’s just another lesson learned (the hard way). Next time you’re generator shopping, check your elevation plans. At least you now know in advance does altitude affect generators.