Solar Power: The Ultimate Guide to Solar Power Energy and Lower Bills: (Off Grid Solar Power Systems, Home Solar Power System) - Mark Prentice, James Bickel (2016)

Book 1. 20 Hacks to Build Your Own Affordable Solar Power System

Chapter 4. Finding the Right Location to Install Your New System

Now that you have gathered all your necessary equipment, it’s time to find the best place to install your system. Remember, you’re making a pretty significant investment, which you’re going to have to live with for some time so you want to make sure that it is in a place where you can maximize the potential benefits to be gained.

You’ve probably seen quite a few pictures of solar panels some located on rooftops, others in fields, and some on the side of a home. How do you know which location is right for you? When deciding on where your system should be located there are three factors you need to keep in mind: position, placement, and orientation.

Position

In general the direction you face your solar panels is also important. Most are of the general opinion that the best direction to point your panels is facing south since that’s where most of the sunlight is coming from but others believe that facing west is the better choice.

The key here is to match supply with demand so you can avoid a blackout at unexpected times. You must think about the times when your demand for power is highest and try to capture the most sun at that time. In general, power consumption follows an arc where the demand begins to rise in the early morning and continues to increase until early afternoon when it begins a gradual decrease with slight variations depending on the region of the world you live in.

The general assumption is more sun means more energy. With that reasoning, you would logically point your panels towards the east or the west. However, when you think of your power arc, you need to know which angle the sun is at during your peak hours of the day. For every home this will be different but by analyzing your power usage you can easily determine the time and direction to position your panels.

Placement

In most cases, solar panels are mounted on the roof of buildings but that is not always the ideal location for maximum efficiency. Rooftops are often preferred because they usually get the most uninterrupted sunlight. They are also out of the way so they won’t take up valuable space that could be used for other things.

However, there are cases where rooftop mounting may not be the most practical choice. The angle of the roof may be too steep or they may be too much shading from surrounding trees or tall buildings.

When it comes to solar energy, even the slightest bit of shade can make a huge impact on how much power you generate. The correct answer to this question as to where to place your solar panels will depend on the area of your home that gets the most sunlight. This may require you to spend time watching the sun and where it hits around your home to determine.

Orientation

Finally, orient your system by placing your solar panels for optimum tilt. This means pointing them at an angle that will capture the most sunlight. It is a simple thing to mount your panels at a fixed tilt and then just let them catch as many rays as they can but it would be so much better if they could be adjusted throughout the year.

Because the sun is higher in the sky during the summer it stands to reason that a fixed panel will only be efficient for part of the year.

By adjusting the angle of your panels with each season you can considerably boost the amount of energy you generate. Below are some basic formulas you can use as a guide to determine the optimum tilt for your home.

Fixed Tilt Panels

If your home is located below 25° latitude, multiply the latitude by 0.87

If your home is located between 25° and 50° latitude, multiply the latitude by 0.76 and add 3.1 degrees.

Note: If you are located above 50° latitude the calculations become more complicated.

It may be best to consult a professional for the guidelines for adjusting your panels in those areas.

Bi-Annual Tilts

If you plan to make your adjustment to the angle twice a year it is best to do it on or around March 30th and September 12th if you live in the Northern hemisphere and on September 29th and March 14th if you are located in the Southern hemisphere.

For homes located between 25° and 50°:

To calculate summer angles use latitude X 0.93 - 21°.

To calculate winter angles use latitude X 0.875 + 19.2°

For Seasonal Tilts

For maximum efficiency you can adjust your tilt four times a year. Use the chart below to get the best angles.

As you can see, the angle at which you orientate your panels will have a heavy bearing on how efficient your system is. These formulas and numbers are suggestions that can vary depending on your exact location however, with a period of trial and error you’ll eventually come up with your own numbers that will maximize the efficiency of your solar system.