The angle of your roof actually has less impact on solar panel performance than the direction your solar energy system faces.
Optimum angle for solar panels.
For los angeles a solar panel tilt of 19 degrees works the best.
Many roofs are going to have slopes between 30 and 40 degrees which means that solar panels can lie flush against the roof and produce enough electricity for attractive returns.
For instance if your latitude is 34 the optimum tilt angle for your solar panels during winter will be 34 15 49.
If you live in the northern hemisphere face them south.
At different times of the year the optimal angle may be slightly or even significantly different.
If you live in the southern hemisphere face them north.
Ideally solar panels would be positioned at an angle of 38 in melbourne equal to the latitude angle of the city 37 81.
The next question is at what angle from horizontal should the panels be tilted.
These angles will give you the best overall output over the course of the year if you re going for a fixed installation.
It turns out that you can do better than this about 4 better.
Optimal electricity production occurs when solar panels face south at a tilt equal to 30.
For starters there is no single ideal angle for solar panels.
The optimum tilt angle is calculated by adding 15 degrees to your latitude during winter and subtracting 15 degrees from your latitude during summer.
To get the best out of your photovoltaic panels you need to angle them towards the sun.
For instance in the san francisco bay area the best solar panel tilt angle is between 22 23 degrees.
Solar output losses when the panel angle is not ideal so what percentage of solar energy do you lose from not having panels mounted at the optimum angle.
The summer optimum tilt angle on the other hand will be 34 15 19.
If you are trying to install solar panels on a steep roof it may not be possible to place panels at the optimal tilt with traditional racking systems.
However if you live in an urban area in the united states you might just be able to find the best angle for the photovoltaic panels with your zip code.
The optimum angle varies throughout the year depending on the seasons and your location and this calculator shows the difference in sun height on a month by month basis.