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This article is published in collaboration with Solar Man Dan your guide to the world of DIY solar systems.

Last week we discussed sizing your DIY solar system and offered a few vendors that supply quality solar panels at fair prices.

There are number factors that determine whether your site is a good DIY solar candidate, and if is is, just exactly where you should install the DIY solar system.

The most common (and simplest) site for residential applications is on the roof. The other 2 types of panel arrays are pole and ground mount. We will first cover roof mounted arrays and then move on to pole and ground mounted.

The south (north if you live south of the equator) facing slope of a pitched roof is the ideal location for a solar array and will give you your best overall performance year round. That being said, west and east slopes come in a close second and can be good alternate sites.

In the previous lesson we showed you how to size a solar system. If you were to divide your system size by 13 (watts per square foot) you would arrive at the square foot of roof area needed to handle your panel array (typically 150 to 450 square feet). Once you have determined that you have sufficient roof area, you need to find out if you have any shading issues. Professional installers use a Solo metric Sun eye ($1,300.00) or a Path finder ($200.00) to plot the suns path over the entire year and accurately pin point any shading issues.

There are a couple of ways around this. The 1st and easiest is to periodically check your proposed panel site between 10:00am and 4:00pm for any developing shadows. If none are present (especially during January and February when the sun is lower and shadows are longer) chances are that you have a good site. There are some utility companies in the USA that will come out and do a shading analysis for free as long as you jump through the right hoops.

Pole and ground mount systems are also great if your roof is not ideal. A pole mount can handle up to 18 panels (3900 watts) per pole. An array of this size will require an 8 inch or larger pole mounted in an extremely deep hole (power auger required). Be sure to check for underground utilities. Ain't nothing worse than drilling through a gas, sewer, water or electric line. Be sure to check your local building and planning dept for any restrictions that they may impose.

Ground mount systems mount directly to earth using special racking and mounting systems (sold in kits). You can view both the pole and ground options at both the web sites I mentioned in the previous article. Stake out the proposed site and check for shadows entering the box during the day (same approach as above).

Generally speaking, the best place to locate the inverter is next to the service panel. By placing it there you will eliminate having to make a lot of labels and maps (required by the building dept for remote inverter locations).

Well there you have it, the first basics of a site analysis.


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