Solar Power and Angles of Panel

After many years of usage and research around this subject, I came to a few simple conclusions.

1. It is the best to simplify your solar energy system. This conclusion is also concern the solar tracking devises. They are marvelous systems but it is more practical to use static set up for common household. Obviously it is necessary optimize angle and orientation for even static frame. Some discussion material about that is below.

2. In many solar usage manuals recommend systems with variable angle to change it for winter or summer seasons. After thinking and using solar panels I came to conclusion to recommend to have closer to vertical orientation for solar photovoltaric systems. This is simply because of usability of solar photovoltaric panels during winter and snow. Weather can influence power output by many times. Therefore if we orient solar panel closer to vertical, snow will not stay on the surface. Same goes for ice, dirt, dust, birds excrement, leaves or debris. This recommendation is not valid for thermal solar heaters. They are more dependent on perpendicular incident solar rays.

3. Best to use building walls if you have any of them facing south. They are perfect for minimization of energy losses by shielding on the North side of panel if you use solar heaters,

For those who still wish to be perfect and utilize solar power to it's maximum usage I wrote a simple calculator for power generation versus angle.

To make this calculator more useful, I included simplified method of calculation of Silicon panel area and output power.

Method is very simplified and based on few practical facts: 900W of solar power per square meter, 15% photoelectric efficiency for an average silicon cell, laws of reflection and practical testing.

Calculator of Solar panel size for different loads Panel area, (m2)
Sun angle a(deg)
Panel angle(deg)
Visibility (%)

  Sun energy 0: Watt
  Panel energy 0: Watt

Panel area is in meters square.

Sun altitude=a is the angle between ground plane (horizontal) and the sun direction. Very simple to determine if you take straigt stick/pen and try to adjust it's position until there will be no shade. If you fix that moment and measure the angle between the earth and the stick, it will be Sun Altitude.

Panel angle=b it is the angle which formed between the horizontal to ground and the plane of your panel. On the avarage it is 45 deg. in most of installations. But PLEASE PUT MINUS in front But it can vary from location to different ideas.

Visibility (%)=Number in percentage to represent your typical weather condition. In this reading material it is how clear is visible sun. Cloudy weather=70%, fog=20%, snow=20%. Note: normally winter and summer vary so much from each other that we propose to split characterization of Solar panel usage by two simplified yearly period- Fall(Autumn)+Winter AND Spring+Summer. Haze factor here is in %. Example- typical winter day without clear sun, but without heavy snow is 50%, Summer day with bright sun is 100%, Heavy rain or snow with overcast is 15%. It is hard to predict this number from day to day, but if you don't want to be bothered by thinking, please put 50 in Visibility (%).

If someone wish to estimate their property or installation site worthiness for energy generation, please simply use 90 and 90 at the Sun angle  And Panel angle.

Luminatek Inc, Inc. All rights reserved.

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