Going For Solar – Solar Site Survey (Step 3)

Ben and Jordan taking measurements

After you have done all the energy efficiency upgrades and behavior modifications around the house to reduce your load, then it is time to think about renewable energy (Caveat – See the caveat for New Jersey at the end of our earlier post).  To get started you should ask a local solar contractor to conduct a solar site survey.

A solar site survey is a thorough analysis of a site to ensure that it is practical for solar.  A good contractor will explain what incentives are available in your area, what size project would work for your location and the what the ballpark price for such a project.  Some may even offer financing plans.  Typically a solar contractor will do this initial site survey at no or minimal cost.

If you want to do a bit more research about incentives, check out the DSIRE list of federal and state renewable energy (and energy efficiency) incentives for your state.

Before getting to far into our solar site survey, I should explain the two types of solar energy to consider – solar photovoltaic (electricity), abbreviated PV, and solar thermal (heat).  Depending on your location and desires one or the other may be more appropriate for you.  You are really lucky if you work both into your site. Now back to our project.

To get started we contacted SunBug Solar to conduct a free solar site survey at our house and determine if our solar dream was possible and estimate how much it would cost.  For help locating contractors near you, check out EnergySavvy.com.

Our Solar Site Survey

Jordan showing our 5 yo son how a Solar PathFinder works

Ben Mayer (he’s the one standing on the little roof above) and Jordan Belknap, an engineer, from SunBug Solar met with Alicia and I for about 2 hours one afternoon.  Ben and I had already talked about our hopes for the project and what we wanted to accomplish.  They had looked at the aerial photos from Bing in advance so they had a sense of what the property looked like and what trees and structures might shade the planned solar array.

While on site, Ben and Jordan were very helpful explaining what they were doing and even took the time to explain it to our son.  Jordan is showing him how they use a Solar PathFinder to map out the path of the sun throughout the day all through the year.  You can see an overhead view of our backyard in the picture below.  If you see the dark things around edges that shows the path of the shade.  Fortunately, this picture was taken near the ground and in the middle of our backyard. The shading is significantly less when measured from in the actual locations of the planned PV array and up on a ladder at the height where the array will eventually be built.

Solar PathFinder shows shading in our yard

A good solar site will have very little shading between the hours of 8am and 4pm all year round. A good solar contractor will then use software to calculate the actual impact of the shading shown.  They import the pictures and then trace the shadow.  The software generates a report and calculates the impact of the shade throughout the year.  In our case, our neighbors had this beautiful hundred plus year old maple tree that was casting a lot of shade.  With this shading our project would have been at the 80% borderline for effectiveness required to qualify for the Commonwealth Solar II Rebates in Massachusetts.  Fortunately for us, a huge branch from the tree broke off and fell into our yard two days before the solar site survey.  An Arborist examined the tree and confirmed that it was rotten and needed to come down.  Our neighbors removed the tree and the shading picture has greatly improved.

Solar PathFinder measures shading all year long

One assumption that I noticed in the numbers I had received from SunBug Solar was the estimated increase in electricity price was 5%.  While I think that is a reasonable value to select, my review of historical residential electricity prices for Massachusetts came back with a 3.5% annual rate of increase for the past 10 years.  A good contractor will rerun the numbers with what you feel are more comfortable numbers and Ben at SunBug Solar was more than happy to oblige several times.

After the solar site survey, SunBug Solar prepared a proposed basic design (number of solar panels, inverter, mounting structure) and cost estimate for us. Given the cost of a PV project (on the order of one or two new cars), you should be sure to get several quotes and estimates from reputable contractors before signing on the dotted line.  Keep in mind this is a 20+ year investment, so spending a little more time upfront will be well worth it.  We will discuss getting multiple bids in our next article in the Going for Solar series.

Happy Greening!
Jon & Alicia

Going for Solar Series

To learn more about residential solar installations, check out our series Going for Solar, which details every step from dreaming about installing solar, through picking a contractor and the steps in construction.  We provide information and advice for every step of the way, as well as different approaches such as paying for it yourself versus leasing a system.  Don’t miss the steps on how much money we saved during our first year of usage!