Am considering installing grid connected solar panels.  Installer wants to go roof mount, I want to do ground mount.  With a one way adjustable gound mount appears about 20% added efficiency is available.  Monthly adjusting of the angle will maximize solar gain.  Can self build a rear brace that will allow for the 30 degress change in angle required.  Should take 30 minutes one a month to manually change the angle on the panels.  looking at a 5300w system.  First installer wanted $11,000 extra to go grond mount.  It was obvious from his comments that they did not want to do anything "different" than their normal installation.  A second installer was much more receptive, saying with our assistance only $1,500 extra for the wiring to the system. Is the 20% gain reasonable?

I find it hard to believe that you will get a 20% gain just from changing the angles. Is there less shading were the ground mount system will be going? Changing the angle alone will not account for a 20% gain. I have done many solar analysis using the solar pathfinder and the software that accompanies it and have not found that large an increase just due to tilt angle. If you do have less shading and can justify the increased cost then go with the ground mount system. Ground mounts are almost always more expensive especially if your making it adjustable. I particulaly like ground mount systems, mainenance is easier and you can clean them regularly to help boost performance, but they are also more easily damaged or stolen. Don't laugh, one guy I know had his 2Kw ground mount system stolen while he was away on vacation.

Tom Pittsley
[email protected]
www.eebt.org

Hi Tom;

     Thanks for your reply.  The 20% figure was a guess.  Checked a few web sites, and that seemed to be the range.  Did not use any of the programs.  What does your program show?  I like the idea of easy cleaning and not polluting the top of my house with panels.  We have enough unobstructed land to do a ground mount and be away from any shade.  Have access to material to do the ground mount so additional cost will be minimum, mostly cost of copper to get to the main.

The angle of solar panel like Solar Panels Australia is important in order to absorb the most energy. To buy a custom make one will cost a bomb.

Hi 1923mack,

Check out the free PVWATTS 2 http://www.nrel.gov/rredc/pvwatts/grid.html calculator at the NREL (National Renewable Energy Laboratory) website. You can easily vary tilt and orientation, as well as vary between fixed and tracking designs for your area, and come up with a better idea of what is possible for different arrangements to see what makes sense for you. The PVWATTS calculator will give you output per month, so you can fairly easily model what happens if you adjust tilt only, by running through it a few times.

Bill

Most likely, the place where you live will determine the type of PV system that would probably be best for you. One of the most flexible Photovoltaic systems would perhaps be a freestanding adjustable solar panel. Not only do you get to make full use of the surface area, but you can point it directly into the sun's path and even adjust it during different seasons to capture optimal amounts of sunlight. Not being attached to your roof, it's more easily accessible at ground level, making for ease of mainenance.

Solar energy panels, BC Solar, Solar installer

i am new but i want to install new roof system with adjustable solar panels witch is the best one site for the solar energy roofing system i will wait your answer.

If you want adjustable panels, it is usually most practical to mount them on a post rather than the roof. In a subdivision with modest sized lots, roof mounting is usually the preferred option, so post mounting is usually limited to rural or semi-rural applications. Do the calculations with PVWATTS first to make sure that the extra headache of having one or two dimensions of adjusting or tracking is worth the effort. Just adjusting the tilt seasonally only provides a modest improvement in energy collected.

Hi Woof,

Is the solar water circuit still on the ground? Maybe it would be of benefit to put it on top of a flat board or metallic panel, painted black? Something with some thermal mass, but won't loose heat to the ground...

Thanks,