These days, when talk of renewable energy fills the air, solar power stands out as one of the brightest answers to climate change and the demand for sustainable energy. The tech has come a long way, too. Solar design isn’t just panels slapped on a roof anymore—it’s a refined process that relies on solid data to make sure every system actually works the way it should.
Google Maps satellite imagery has become a go-to shortcut for people sketching out solar projects, mainly because it’s right there at your fingertips. But here’s the catch: what looks helpful at first can’t really give you the reliable numbers and details you need for smart planning. That’s where real solar site surveys step in, offering a much clearer, more trustworthy picture of how a system will perform in the real world.
Google Maps has changed the way we see the world. That little satellite view button lets you zoom in on just about anywhere, pulling up sharp aerial images with only a few clicks. It’s easy, fast, and no wonder it’s become the go-to for so many things—including early solar design work.
And to be fair, it does have its perks when used for solar projects:
Global coverage: Google Maps offers coverage of vast geographical areas worldwide, making it a convenient tool for accessing imagery from almost any location.
Easy accessibility: The platform is user-friendly, allowing individuals with little technical knowledge to access aerial images with ease.
Quick preliminary assessment: For an initial overview of a site's solar potential, Google Maps can offer a rapid glimpse of nearby obstructions, terrain, and available space for solar panels.
The Limitations of Google Maps Satellite Imagery for Solar Design
While Google Maps has its merits, it falls short in providing the level of precision required for solar design. The following are the primary limitations of relying solely on Google Maps satellite imagery.
Outdated imagery:
The thing with Google Maps is the image quality isn’t consistent. If you’re looking at a busy city, the pictures can be sharp enough to catch the smallest details. But head out to the countryside or a less developed area and suddenly it’s all fuzzy and pixelated. When that happens, good luck trying to figure out something as specific as where shadows might fall—it’s nearly impossible to trust what you’re seeing.
Here, you can see a side-by-side comparison of two photos of the same address. The photo on the left was a drone photo we took during a site survey. The photo on the right was a screenshot of that site’s Google Maps satellite imagery.
Inconsistent resolution
The clarity of Google Maps really depends on where you’re looking. In cities, the images can be sharp and detailed, almost like you’re standing right there. But once you shift to rural areas or places that don’t get updated often, the pictures can turn blurry and pixelated. That makes it tough to pick out important details—like whether a roof is shaded at certain times of day—which are critical for planning solar.
Limited information on shading analysis
Figuring out shade is one of the most important parts of solar design. Even a little shadow from a tree or a building nearby can cut into how much energy the panels produce. The problem is, Google Maps can’t really show you how those shadows move as the sun shifts during the day or across different seasons. Without that real-time view, you’re left guessing, and guessing isn’t good enough when efficiency is on the line.
Lack of sun-path data
To really get solar right, you have to know how the sun moves over the course of a year. That’s what helps you figure out the best angle and direction for the panels so they soak up as much light as possible. The snag is, Google Maps doesn’t give you that kind of sun-path data. Without it, you’re missing a big piece of the puzzle—especially if you’re setting up an off-grid system where precision really matters.
Difficulty in measuring roof dimensions
When it comes to rooftop solar, knowing the exact size of the roof is everything. You need solid measurements to figure out how many panels will actually fit. The catch? Google Maps only gives you rough tools for measuring, and they’re not always accurate. That can throw off your calculations and leave you with the wrong estimate of how much space you really have to work with.
What about Solar Site Surveys?
Instead of leaning only on Google Maps, there’s a much more reliable way to get the details you need: a solar site survey. This is where the experts roll up their sleeves and step onto the property. They walk around. They take real measurements. They spot things a computer screen would miss, and basically get the full picture you need.
There are a variety of advantages of solar site surveys, including:
Real-time data collection: Solar site surveys provide real-time data, ensuring that the information gathered is current and up-to-date.
High precision: Professionals conducting solar site surveys use specialized tools and equipment to collect precise data on shading, roof dimensions, obstructions, and sun-path analysis. For example, Exactus Energy’s site surveys are able to get quarter-inch level accuracy on commercial project data, and inch-level accuracy on residential project data.
Customized design: Solar site surveys enable installers to tailor the solar system design to the specific needs and conditions of each site, maximizing energy production and efficiency.
Identifying potential challenges: Site surveys allow for the identification of potential challenges or issues that may not be visible through satellite imagery, such as structural concerns or electrical limitations.
Accurate financial projections: By obtaining accurate data through solar site surveys, financial projections for the solar project can be made with greater confidence, leading to more reliable ROI estimates.
Google Maps is handy for plenty of everyday uses, but solar design asks for a level of accuracy it just can’t deliver. The images might be old, the quality jumps around from place to place, and it doesn’t give you live shading data. Put all that together, and it’s clear—you can’t rely on it to design a solar system the right way.
Site surveys, on the other hand, give you the accuracy and fresh data that solar projects really depend on. When professionals come out and inspect the property in person, they can collect the kind of details that make custom designs possible, spot challenges before they turn into problems, and even give you clear numbers for costs and savings. If you want the full breakdown of what a site survey can do for your project, check out our earlier post.
As the solar industry continues to grow, embracing solar site surveys as a standard practice will undoubtedly lead to more efficient and reliable solar installations, contributing to the broader goal of a sustainable and renewable energy future.