How much power can you get vs advertised rated of the solar panel? What % worth?

[miogpsrocks]

What % actually power do you get vs the rated advertised capacity of your solar panel?

For example if you have a 200W panel, how many real actual watts do you get?

Like 50% maybe?

[J.P.M.]

The question needs to be more specific.
You looking for possible max. % of STC output ?
Under what input conditions?

Try this: Under a clear summer midday sun and maybe a 25 C. ambient air temp. with no obstructions and a slight breeze, a reasonable quality 200W PV panel pointed directly at the sun may produce power at a rate something like around 170W or maybe 85% of STC rated output.
Change any of those parameters or lots of others and the output will change and will probably be less.

Check out a free PDF download of "Solar Power Your Home for Dummies" for why things vary so much.

[miogpsrocks]

The question needs to be more specific.
You looking for possible max. % of STC output ?
Under what input conditions?

Try this: Under a clear summer midday sun and maybe a 25 C. ambient air temp. with no obstructions and a slight breeze, a reasonable quality 200W PV panel pointed directly at the sun may produce power at a rate something like around 170W or maybe 85% of STC rated output.
Change any of those parameters or lots of others and the output will change and will probably be less.

Check out a free PDF download of "Solar Power Your Home for Dummies" for why things vary so much.

Thanks, I will try to find that PDF.

When people advertise the size of their solar panel array, are they saying the advertise size of the solar panels added up or the actual power they are getting?

For example, if someone said they have a 5KW system, does that mean an advertised 5KW if you add up all the advertised watts of their solar panel or it is adding up the actual watts on a optimal sunny day. I know the area makes a different and angle to the sun, temp, etc..

Thanks.

[Mike 134]

It's the advertised watts. Very seldom do you actually hit that much output; I have just a few times, but it needs to be a colder partly sunny day at "solar noon"

[J.P.M.]

Thanks, I will try to find that PDF.

When people advertise the size of their solar panel array, are they saying the advertise size of the solar panels added up or the actual power they are getting?

For example, if someone said they have a 5KW system, does that mean an advertised 5KW if you add up all the advertised watts of their solar panel or it is adding up the actual watts on a optimal sunny day. I know the area makes a different and angle to the sun, temp, etc..

Thanks.

You're welcome.

I have what's commonly referred to as a "5 kW system". My system has a total of 16 panels with each panel having an STC rating of 327 W.
So my system size = (16 panels) * (327 STC W/panel) = 5,232 STC W.

PV systems with all panels of the same STC size are most commonly referred to as having a "system size" equal to the STC rating of each panel in the system multiplied by the number of panels in that system with that product usually rounded up or down to the nearest total STC kW or 0.1 STC kW. For example, some folks would call my system size = 5.2 STC kW or simply a "5.2 kW system".

See the dummies book for info on what STC means.

[J.P.M.]

xyz
QUOTE=J.P.M.;n443275]XYZ


You're welcome.
Added:
Similar to a vehicle manufacturer not advertising the actual power output of their vehicles' engines under a variety of actual or operating conditions and so use SAE or other standard type ratings to identify power, PV mfgs. and vendors cannot or will not talk about output under what is in actuality an almost infinite number of operating conditions.
In either case (vehicles or PV systems) it just gets too messy and confusing to talk about a variety of operating conditions so some form of standard comparison methods are used which may or may not have any relation to common operating outputs.

I have what's commonly referred to as a "5 kW system". My system has a total of 16 panels with each panel having an STC rating of 327 W.
So, my system size = (16 panels) * (327 STC W/panel) = 5,232 STC W = 5.232 kW.

PV systems where all panels are of the same STC size are most commonly referred to as having a "system size" equal to the STC rating of each panel in the system multiplied by the number of panels in that system with that product usually rounded up or down to the nearest total STC kW or 0.1 STC kW. For example, some folks would call my system size = 5.2 STC kW or simply a "5.2 kW system".

See the dummies book for info on what STC means.[/QUOTE]

[miogpsrocks]

xyz
QUOTE=J.P.M.;n443275]XYZ


You're welcome.
Added:
Similar to a vehicle manufacturer not advertising the actual power output of their vehicles' engines under a variety of actual or operating conditions and so use SAE or other standard type ratings to identify power, PV mfgs. and vendors cannot or will not talk about output under what is in actuality an almost infinite number of operating conditions.
In either case (vehicles or PV systems) it just gets too messy and confusing to talk about a variety of operating conditions so some form of standard comparison methods are used which may or may not have any relation to common operating outputs.

I have what's commonly referred to as a "5 kW system". My system has a total of 16 panels with each panel having an STC rating of 327 W.
So, my system size = (16 panels) * (327 STC W/panel) = 5,232 STC W = 5.232 kW.

PV systems where all panels are of the same STC size are most commonly referred to as having a "system size" equal to the STC rating of each panel in the system multiplied by the number of panels in that system with that product usually rounded up or down to the nearest total STC kW or 0.1 STC kW. For example, some folks would call my system size = 5.2 STC kW or simply a "5.2 kW system".

See the dummies book for info on what STC means.

[/QUOTE]

My 195W panels only product 100W given it's mostly flat angle for my flat roof. So 50 panels will only product 5,000W even know its STC is almost 10,000W

[J.P.M.]

My 195W panels only product 100W given it's mostly flat angle for my flat roof. So 50 panels will only product 5,000W even know its STC is almost 10,000W[/QUOTE]

Entirely possible given the near horizontal panel orientation and low(er) solar altitude angle this time of year.
Depending on latitude, near horizontal panel orientation reduces panel output.
Horizontal panels will also most likely require more cleaning to keep the performance from deteriorating even more due to quicker panel fouling.
Near horizontal panel orientation tends to turn PV panels into shallow sand boxes. The dirt/dust/airborne junk stays put more than on tilted panels and will also cake up when it doesn't entirely wash off in the rain/dew but just evaporates and leaves hardened mud behind.
That tends to make panel performance drop quicker and stay that way.

[miogpsrocks]

My 195W panels only product 100W given it's mostly flat angle for my flat roof. So 50 panels will only product 5,000W even know its STC is almost 10,000W

Entirely possible given the near horizontal panel orientation and low(er) solar altitude angle this time of year.
Depending on latitude, near horizontal panel orientation reduces panel output.
Horizontal panels will also most likely require more cleaning to keep the performance from deteriorating even more due to quicker panel fouling.
Near horizontal panel orientation tends to turn PV panels into shallow sand boxes. The dirt/dust/airborne junk stays put more than on tilted panels and will also cake up when it doesn't entirely wash off in the rain/dew but just evaporates and leaves hardened mud behind.
That tends to make panel performance drop quicker and stay that way.

[/QUOTE]

I may try to put somewhat of a angle on it( 5-10 degree) to avoid these things. Maybe I should even consider a sprinkler system that shoots them during hot part of the day to gain cooling/cleaning.

[J.P.M.]

I may try to put somewhat of a angle on it( 5-10 degree) to avoid these things. Maybe I should even consider a sprinkler system that shoots them during hot part of the day to gain cooling/cleaning.[/QUOTE]

It's probably not a good idea to spray water on dry glass surfaces that may well be 30 C or so above the ambient air temp. That tends to crack glazings.