The tilt and azimuth of the solar panels in a particular location does not directly affect tree shading. That is determined by simple geometry...the sun, the tree, and the panel. When the line from the sun to the panel goes through the tree, you get shading, regardless of how the panels are oriented.
However, given that some tree shading may occur, the tilt and azimuth can be arranged so as to maximize solar collection during the unshaded periods. So, for example, if there is going to be tree shading in the south east, orienting the panels southwest will maximize solar collection during the latter part of the day when there is no shading.
Interestingly, in the 29.5 degree latitude in which I live, the summer solstice sun rises in the northeast and sets in the northwest, going just a tiny bit south at midday. Near dusk, my house is shaded by trees in back lot to my northwest. So at this time of year, trees to the south do not cause any shading, though they do cause shading for most of the year.
To get away from trees, sometimes panels are best located in places you wouldn't normally think appropriate, such as on the north side of house (to get as far away from a southern tree as possible). Then they can be oriented straight up (which gets 89% of the available sun on annualized basis) or tilted south (if the location is finally far enough from tree not to shade the southern sun). However, in such a scenario the roof slope itself may block the sun. For example, suppose I have panels on east side (relatively tree free) of my north-south main house ridge pointed straight up. The sun will set on the panels when it gets to an angle greater than the roof slope. Actually, since this is a mere 5/12, that won't be until rather late afternoon, but it's still a consideration.
Solar panels nowadays are incredibly debilitated by shade. Even a tiny spot of shade can reduce panel output by 50%, and a small line across the panel can reduce output by 100%. IMO panels need to be more shade tolerant, a multicellular design might help.
However, given that some tree shading may occur, the tilt and azimuth can be arranged so as to maximize solar collection during the unshaded periods. So, for example, if there is going to be tree shading in the south east, orienting the panels southwest will maximize solar collection during the latter part of the day when there is no shading.
Interestingly, in the 29.5 degree latitude in which I live, the summer solstice sun rises in the northeast and sets in the northwest, going just a tiny bit south at midday. Near dusk, my house is shaded by trees in back lot to my northwest. So at this time of year, trees to the south do not cause any shading, though they do cause shading for most of the year.
To get away from trees, sometimes panels are best located in places you wouldn't normally think appropriate, such as on the north side of house (to get as far away from a southern tree as possible). Then they can be oriented straight up (which gets 89% of the available sun on annualized basis) or tilted south (if the location is finally far enough from tree not to shade the southern sun). However, in such a scenario the roof slope itself may block the sun. For example, suppose I have panels on east side (relatively tree free) of my north-south main house ridge pointed straight up. The sun will set on the panels when it gets to an angle greater than the roof slope. Actually, since this is a mere 5/12, that won't be until rather late afternoon, but it's still a consideration.
Solar panels nowadays are incredibly debilitated by shade. Even a tiny spot of shade can reduce panel output by 50%, and a small line across the panel can reduce output by 100%. IMO panels need to be more shade tolerant, a multicellular design might help.
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