Panels not generating promised output

[chunkychen]

Hi folks,

I have 20 250W Mage panels installed on my roof starting at the end of January. They are on the western side of the roof (due to HOA regulations) and are connected w/ enphase micro-inverters. I've enjoyed looking at the power that my panels are generating despite the snow in Cleveland, however, it bothers me that I haven't seen it come close to the max output. Probably the highest that I've seen when I look at the enlighten monitoring software is 4.3 KW. Does this seem strange? I know I'm losing something by having them face a non-opportune direction, but I thought it would be closer to the promised wattage. Is this something I should talk to my installer about?

thanks,
Mike

[SunEagle]

Hi folks,

I have 20 250W Mage panels installed on my roof starting at the end of January. They are on the western side of the roof (due to HOA regulations) and are connected w/ enphase micro-inverters. I've enjoyed looking at the power that my panels are generating despite the snow in Cleveland, however, it bothers me that I haven't seen it come close to the max output. Probably the highest that I've seen when I look at the enlighten monitoring software is 4.3 KW. Does this seem strange? I know I'm losing something by having them face a non-opportune direction, but I thought it would be closer to the promised wattage. Is this something I should talk to my installer about?

thanks,
Mike

Most PV panels have a peak output when the sun is at it's highest point and the panels are aimed right at it. If the sun is at an angle to the panels or is lower in the sky then your panels will not be producing their rated value in watts.

[chunkychen]

Gotcha- so it probably means that I'll never quite get the full output unless I take the panels off and put them at the south side of the house.

thanks for the advice!
Mike

[Ian S]

Gotcha- so it probably means that I'll never quite get the full output unless I take the panels off and put them at the south side of the house.

thanks for the advice!
Mike

Don't forget, the sun just crossed the equator a week ago so is still fairly low in the sky - if your panel mounting angle with the horizontal is anything near typical, you won't get maximum output until around June and even then it will have to be a sunny cool day. I'd say 4.3 kW output at this time of year with your less than ideal west orientation is pretty good.

[SharpT]

Don't forget, the sun just crossed the equator a week ago so is still fairly low in the sky - if your panel mounting angle with the horizontal is anything near typical, you won't get maximum output until around June and even then it will have to be a sunny cool day. I'd say 4.3 kW output at this time of year with your less than ideal west orientation is pretty good.

I haven't run the cals and don't have all your details, but 4.3kWh vs 5kW system on a West facing system this time of year seems pretty good.

[egghead2004]

250 watt panels, but 215 inverters

Hi folks,

I have 20 250W Mage panels installed on my roof starting at the end of January. They are on the western side of the roof (due to HOA regulations) and are connected w/ enphase micro-inverters. I've enjoyed looking at the power that my panels are generating despite the snow in Cleveland, however, it bothers me that I haven't seen it come close to the max output. Probably the highest that I've seen when I look at the enlighten monitoring software is 4.3 KW. Does this seem strange? I know I'm losing something by having them face a non-opportune direction, but I thought it would be closer to the promised wattage. Is this something I should talk to my installer about?

thanks,
Mike

Mike,

The Enphase micro-inverters are rated at 215W output, although some peak out at 225W, so your numbers seem pretty good.
20 * 215W = 4.3 KW.

[inetdog]

Gotcha- so it probably means that I'll never quite get the full output unless I take the panels off and put them at the south side of the house.

thanks for the advice!
Mike

You can enter your location and roof angle information at PVWatts and get a pretty good comparison of the output for different angles and orientations through the whole year. Do that before you even think of moving your panels.