Solar Power output-Peak Hours vs Total Hours

[suseuser]

I'm not sure where this question belongs so I'm throwing it out here. Most calculations for panel output use "peak" solar power output. In my area it's about 5 hours a day. But, early in the morning say around 9am I'm getting at least 1 amp of power from my 100W panels. I'm curious why this power production isn't included into the calculations? There are 5 extra hours (2.5hrs in the morning and 2.5hrs at night) of non-peak power being put into the battery. In this case you are getting an additional 5A of power not accounted for.

[ButchDeal]

I'm not sure where this question belongs so I'm throwing it out here. Most calculations for panel output use "peak" solar power output. In my area it's about 5 hours a day. But, early in the morning say around 9am I'm getting at least 1 amp of power from my 100W panels. I'm curious why this power production isn't included into the calculations? There are 5 extra hours (2.5hrs in the morning and 2.5hrs at night) of non-peak power being put into the battery. In this case you are getting an additional 5A of power not accounted for.

peak is not a common term for sun hours. The common term it sounds like you are talking about is "Sun Hours"
Solar production ramps up and then back down in a parabolic curve of potential. Sun Hours is a rule of thumb to calculate production so that you can simply multiply the sun hours by your wattage installed measured in STC power so in your case a 100w STC PV module times 5 sun hours comes up with 500wh
During your 5 hours you what you think is "peak" you are getting LESS than 100W from your PV module so the shoulder hours added in gets your rule of thumb estimate of 500Wh per day.

Amps does not work like you are talking and your calculations around amps is just not valid.

[JSchnee21]

PV production modelling software, for example, e.g. PV Watts, do take into consideration the movement of the sun across the sky by latitude and month. Roughly speaking the shape of the production curve is an inverted parabola (more or less) assuming no other interfering factors (shade, clipping, etc.). That said, peak sun hours, usually no more than 3 to 5 hours per day (again varying by latitude and season), generally accounts for ~60-70% or more of your total production. Solar panels really only work well when the sun is essentially perpendicular from the face of the panel so orientation and inclination of the panel (and the sun in the sky) have a pretty significant impact.

[Mike90250]

The amount of power is so low, and with some weather variation, not reliable to bother to count.

[suseuser]

peak is not a common term for sun hours. The common term it sounds like you are talking about is "Sun Hours"
Solar production ramps up and then back down in a parabolic curve of potential. Sun Hours is a rule of thumb to calculate production so that you can simply multiply the sun hours by your wattage installed measured in STC power so in your case a 100w STC PV module times 5 sun hours comes up with 500wh
During your 5 hours you what you think is "peak" you are getting LESS than 100W from your PV module so the shoulder hours added in gets your rule of thumb estimate of 500Wh per day.

Amps does not work like you are talking and your calculations around amps is just not valid.

I know the extra power doesn't seem like much. But, in this case it actually is enough power to keep a charge on the battery with no load. I only referenced "Amps" because that's what indicated on the watt meter power analyzer. I'm not sure what the meter was measuring when it indicated "amps". I assumed it was amps.

[ButchDeal]

I know the extra power doesn't seem like much. But, in this case it actually is enough power to keep a charge on the battery with no load. I only referenced "Amps" because that's what indicated on the watt meter power analyzer. I'm not sure what the meter was measuring when it indicated "amps". I assumed it was amps.

amps like watts are instantaneous reading not a storage capacity like Wh or kWh.
further amps is kind of meaningless without knowing the exact voltage to convert to a storage capacity.

I am not implying that the power on the shoulders is meaningless but rather it is included in the sun Hour rule of thumb already.

[littleharbor]

Sun hours are a way of figuring how much power to expect of a fixed array. If you want to harvest more than 5 sun hours a day from your solar you can do one of two things.
1, Use a single or dual axis tracker. These tend to be costlier and require more maintenance than...#2
2, Virtual tracking which is to spend the money you would on a tracker on more solar panels and orient your panels to some degree east of due south and west of due south.. While you'll never see output of panels match your peak STC rating , your production day will last longer.

[suseuser]

Sun hours are a way of figuring how much power to expect of a fixed array. If you want to harvest more than 5 sun hours a day from your solar you can do one of two things.
1, Use a single or dual axis tracker. These tend to be costlier and require more maintenance than...#2
2, Virtual tracking which is to spend the money you would on a tracker on more solar panels and orient your panels to some degree east of due south and west of due south.. While you'll never see output of panels match your peak STC rating , your production day will last longer.

I guess I could also connect my watt meter between the panel and the controller and measure the power output from the panel from sun up until sun down. But, I don't think there is a reason to get that precise a measurement. I was just surprised that there was enough power generated outside of "sun hours" to keep my battery charged without a load. Or in this case to balance out the power "cost" of my inverter being on.