How to maximize the area of the roof?

[Miguel Sousa]

[LEFT]I'm studying a hypothetical building to be used for residential uses. It is assumed that every solar panel added would be cost efficient, due to the huge number of apartments involved.
The roof has a 100% illuminated flat area, south oriented. I assumed a 1m distance from roof edges due to safety reasons, both with panels against the wind, and for the personal installing. Since the area is limited, and every solar panel contributes the most, I assumed a tilt angle of 10

[organic farmer]

[LEFT]I'm studying a hypothetical building to be used for residential uses. It is assumed that every solar panel added would be cost efficient, due to the huge number of apartments involved.
The roof has a 100% illuminated flat area, south oriented. I assumed a 1m distance from roof edges due to safety reasons, both with panels against the wind, and for the personal installing. Since the area is limited, and every solar panel contributes the most, I assumed a tilt angle of 10

If your building code requires a 1m distance from the edges of your roof, then you have few opportunities to 'maximize' the area.

[sdold]

Miguel, how are you entering your message text? Are you typing it in to the forum on a computer, or doing something else, like copying/pasting from another program, or using a mobile device?

[Miguel Sousa]

I typed it in my PC . It logged me off in the middle of it, so I did try to copy paste it from the website. Should I try to type manually only?

[J.P.M.]

As Butch notes, what experienced designers look for in situations similar to yours is to maximize production and/or maximize cost effectiveness per installed STC kW. or some mix of design parameters that maximizes ROI.

There is software that can estimate shading and estimate output reductions from that shading for arrays that consist of rows of panels set at some azimuth and elevation on a horizontal surface such as a roof.

See SAM from NREL for a taste of what's involved, or any number of decent texts on solar energy.

After that, iterate with building code requirements and panel types and building shading parameters. You'll seldom get the max. possible output, but a good design will balance the possible with cost effectiveness.

As a rough first approx., and FWIW, because the penalty from self shading is somewhat dependent on projected area of an array, I've found over the years that if I use the annual output of a horizontal array on a horizontal roof, reduced in area for parapet and other shading etc., that gets me within spittin' distance of the output of an array at most any other reasonable azimuth and tilt pretty much regardless of tilt once shading of rows by other rows closer to the equator is accounted for. Not exact, but sometimes/often useful tool in the preliminary stages of design in that it will save a bit of work by not going down the wrong path and then finding out it was a dead end after a lot of work.

[sdold]

I typed it in my PC . It logged me off in the middle of it, so I did try to copy paste it from the website. Should I try to type manually only?

Yeah, or at least go back and take a look after posting to make sure it's all there. The website has problems with copied/pasted text, as well as text entered from certain mobile devices. I just wondered what caused your problem. Thanks and sorry for the trouble.