paula wrote:my generator powered my ac in my driveway. but when i got to playa. it didn't make enough juice. any of you super smartie pants can 'splan it to me?
Yes. Many years ago, I discovered the same thing and posted about it here. Altitude and Temperature
Altitude and temperature can have adverse effects on generator output. Let’s begin by looking at the effects of altitude. Gasoline powered gensets will decrease by 3.5% in power for each 1,000 feet of elevation above sea level.
Example: A 6 KW generator in Denver, CO
5,000 ft. elevation
3.5 x 5 =17.5% decrease
Maximum output is now 4,950 watts.
High temperatures can also decrease the efficiency of your generator by 1% for each 10° above 60° Fahrenheit.
Example: A 6 KW generator in Phoenix, AZ
It’s Labor Day weekend; the temperature is 120°
120° - 60° = 6 x 1 = 6% decrease
Maximum output is now 5,640 watts.
Now let’s see what happens when you combine high altitude and high temperature.
Example: 6 KW Generator in Denver, Colorado
Elevation: 5,000 ft. elevation
Temperature: 100° Fahrenheit.
Altitude: 3.5% x 5 =17.5% decrease
100° - 60° = 4 x 1 = 4% decrease
Total decrease = 21.5%
Maximum output is 4,710 watts.