Shading Analysis: How To Do It And Get It Right
Inaccuracy in shade reports is all too common.
If you put ten different people up on the same roof with the same handheld shading analysis device or behind the controls of a do-it-yourself (DIY) software platform, you’ll most likely end up with ten different results. And these inaccurate shade reports often cause many problems for contractors and customers alike.
After all, the amount of shade on a roof directly affects the electric production capacity of a system, which in turn affects everything from the type of equipment you should order to the consumer’s return on investment.
If you didn’t even realize this was an issue, you’re not alone. Handheld devices have been the go-to in the industry for so long that many contractors haven’t given it a second thought. Many solar design software providers tout shading accuracy, with the unspoken caveat that the accuracy is dependent on the user, but a shade analysis can actually make or break you. Especially as competition in the solar industry becomes more and more fierce.
So we’re going to touch on a few issues related to shading analysis to help you wrap your head around the big picture. Here’s what we’ll look at in this article:
- Is accuracy all that important when doing a shading analysis?
- The real cost of an inaccurate shading analysis
- Major benefits of an accurate shading analysis
- Different tools for the job
- Best practices to reduce shading loss
- Impact of shading analysis on your customers
Let’s get started.
Is accuracy all that important in a shading analysis?
Short answer: YES.
Accuracy is of the utmost importance. The amount of sunlight that reaches a roof is directly correlated to the financial feasibility of a system.
Longer, more detailed answer: Depending on the solar project location or how the project is funded, the market has varying impressions on whether the shading analysis needs to be accurate. For example, certain state programs and financiers have specific requirements for the method used to calculate shade and often set minimum thresholds of shade for project viability.
On the residential side, however, there is no “standard” to be measured against. The industry has certain methods of estimating shade that are accepted, but the accuracy of each is difficult to quantify, leaving no real source of truth to compare it to.
Also on the residential side, there’s a misconception that shading accuracy only matters if you’re offering a performance guarantee or Power Purchase Agreement (PPA). But an incorrect electricity production estimate affects the homeowner’s ROI and satisfaction as a customer — whether there’s a guarantee or not. And consumer protection has become a hot topic in solar, as many homeowners were sold or promised savings that didn’t pan out.
So, even though shading analysis accuracy isn’t required in all parts of the solar industry yet, it’s certainly important. This brings us to the next issue… The cost of inaccuracy.
The real cost of inaccurate solar panel shading analysis
The impact of shade is probably the largest loss when it comes to estimating the electricity production of a solar PV system. (Other factors include things like location, weather, equipment, and roof plane direction.)
So if your analysis isn’t accurate, you’ll likely end up with a big mismatch between the estimated production you promised the consumer and the actual production given the amount of shade on the roof. As we mentioned above, this has a major impact on the consumer.
But it also affects contractors. There are many hidden costs associated with inaccurate shading analysis that directly affect your profitability and long-term success in the industry. Namely, increased customer acquisition costs due to poor customer experience and low referral rates and increased labor and operational costs due to change orders and high cancellation rates.
Major benefits of accurate shading analysis
As you’re probably picking up by now, one of the main benefits of an accurate shading analysis is that it improves the accuracy of your estimated electricity production. But there’s more… Here are five major benefits of doing an accurate shading analysis.
5. Adds another layer of consumer protection
Unfortunately, there’s no standard unit of measure for shade when it comes to residential systems. And many user-operated tools produce variable results — a combination that leaves consumers in a tricky spot. An accurate shade analysis that relies on a 3rd party source of truth, however, protects consumers from both dishonest vendors and honest, but inaccurate estimates.
Types of tools for performing a solar shading analysis
Now that you know how much an accurate shading analysis can benefit your business, here are a few types of tools that can be used to estimate shade on the roof surface.
Tool category #4: Drones
Drones offer the same quality and consistency as Inform Advanced when it comes to performing a shade analysis. However, using a drone requires scheduling an external site visit (which could be limited by weather conditions), acquisition and maintenance of equipment, user training, and dealing with other complications related to operating the drone
Best practices to properly account for shade
In this section, we’re going to go over a few best practices when it comes to shade analysis.
4. Set standards to maintain consistency in measurement
Besides human error, one of the biggest issues with handheld devices is subjectivity. For example, if given the same set of SunEye data, designers can choose which images are used to produce solar access percentages and if and how individual SunEyes are corrected to adjust for the auto-fill of shaded areas. So, setting standards to maintain consistency among users will help to reduce shading loss due to subjectivity.
Wrapping up: understand the impact of shading analysis accuracy on your customers
After solar tax credits, the cost for a solar panel system on an average-size house in the U.S. ranges from $11,144 to $14,696. This is no small thing for most consumers, many of whom finance the project and depend on energy savings to offset their loan payments.
So if their system doesn’t produce the amount of electricity expected due to an inaccurate shading analysis, the energy savings may not be enough to offset the loan — putting many consumers in a bad financial position.
As you can imagine, this doesn’t inspire a lot of confidence in your company from the customer’s perspective. In fact, many customers feel swindled when this happens, leading to irate phone calls, negative reviews or word-of-mouth, and even lawsuits.
On the flip side, if a system produces electricity as expected (or even more so), customers will be giddy with excitement as they watch their gamble pay off, likely referring your company to family, friends, and neighbors.
So even though the industry doesn’t require you to meet any standards with your shading analysis, it’s important to understand that it has an outsized impact on your customers, which in turn impacts your credibility in the solar installation business.