Inaccurate Solar Site Surveys: A Bottleneck in Delivering Excellence

We understand that the solar EPC industry is becoming increasingly competitive. Each project represents a race to optimize efficiency and provide the greatest value for your customers. In this fierce competition, it's likely that you may be neglecting a crucial factor that has a significant impact on both: the precision of your site survey.  

Discover the drawbacks of inaccurate site survey data and find out how accuracy can give you an edge over your competitors.  

Why Site Surveys are Frankly Critical

When you think about the foundation of a successful solar design project, it all starts with the site survey. These surveys provide essential information on;

  • Solar Irradiance: It is imperative to know how much sunlight the site receives daily and annually.
  • Shading Analysis: Identifying potential obstacles might cast shadows on the panels, such as adjacent trees, buildings, or other structures.
  • Roof Condition and Orientation: For rooftop installations, understanding the roof's condition, angle, and direction is crucial.
  • Integrating with Existing Electrical Infrastructure: The capability of existing electrical system must be evaluated to estimate the interconnection requirements.
  • Understanding Specific Customer Requirements: The tailor-made solutions will aid you to deliver what exactly your customer needs, matching their expectations with reality.  

Without accurate data in these areas, you’re sure to lose customers over time. This is the first step, and you can never go wrong here!

Modern EPCs often use advanced tools to reduce the margin of error. However, even the most advanced tools are only as good as the people using them. Human error can still creep in, leading to inaccurate data collection.

Granular Data Points Matter in Solar Site Survey

It is no wonder that a comprehensive site survey, conducted by a qualified professional, is always an essential investment for EPC firms. Here's a deeper dive into some critical data points and their technical implications:

  • Roof Measurements and Structural Analysis: Precise measurements of the roof's dimensions (length, width, and area), pitch, and structural member data are crucial. This information is vital for:
    • Solar Panel Placement: Accurate measurements ensure optimal panel placement, maximizing the overall usable space, minimizing the risk of collapsing or structural failing.  
    • Structural Load Bearing Capacity Analysis: Precise assessment of load requirements safeguards your solar system against structural failures like wind, snow, and more.

  • Solar Resource Assessment: Beyond basic sun shading site analysis, a detailed solar resource assessment utilizes software and historical weather data to precisely calculate the amount of direct and diffuse solar irradiance a site receives throughout the year. This information is paramount for:
    • System Design and Energy Production Estimates: Accurate solar resource data allows for the selection of the most appropriate panel type and inverter capacity to optimize energy production based on the client's specific needs.
    • Performance Ratio (PR) Modeling: This data is crucial for modeling the system's anticipated Performance Ratio (PR) using Generation Potential Simulation Software, a key metric that measures the performance of the system.

  • Electrical System Capacity and Interconnection Analysis: A thorough assessment of the existing electrical system's architecture, energy consumption data, available breaker slots, etc. is essential. Additionally, interconnection requirements with the local utility need to be investigated. This information is critical for:
    • Inverter Selection and System Sizing: The electrical system's capacity dictates the maximum allowable inverter size and overall system design. Consider an example of Illumine-i. Our electrical engineers excel in designing intricate wiring and complex battery sizing, optimizing your solar energy system to perfection.
    • Interconnection Feasibility and Cost Estimation: Understanding interconnection requirements allows for early identification of potential upgrades needed and associated costs.

Now, what if this process goes wrong? What's the impact?  

The Domino Effect of Inaccurate Data

Let's explore the potential consequences of inaccurate data obtained during a poorly executed solar site survey:

  • Overbudgeting: Overestimating system needs can result in an oversized solar system, driving up the initial cost unnecessarily. Your customers faced with unexpectedly high quotes may reconsider their investment or seek alternatives, ultimately resulting in a lost sale. Imagine a potential client excited about going solar but deciding against it due to a budget-busting estimate. This not only impacts your immediate revenue but also diminishes the potential for future referrals, as the disappointed customer is likely to choose a competitor instead.
  • Underbudgeting: On the flip side, underestimating the required system size can lead to a system that fails to meet the homeowner's energy needs. This miscalculation means absorbing additional costs to rectify the undersized system, which erodes your profit margins over time. Consider a scenario where a customer realizes their solar savings fall short of promises, leading to dissatisfaction and additional expenses on your part to make things right. The need to make unplanned adjustments and upgrades can drain resources and reduce overall profitability.
  • Increased Overheads: Inaccurate data can lead to repeated site visits, additional labor, and administrative efforts to rectify mistakes. These extra activities increase your operational costs and can put a strain on your team's resources. For instance, having to revisit a site to adjust or remeasure the system not only disrupts your schedule but also adds to your overhead expenses, making your operations less efficient and more costly over time.
  • Damaged Reputation: Incorrect data can result in systems that don't fit the designated space or require unexpected modifications, causing installation delays and increased costs. Faced with these inconveniences, customers may feel frustrated and share their negative experiences, which can impact your business reputation. As you know, poor reviews and negative word-of-mouth can have far-reaching effects, potentially discouraging prospective clients from considering your services!

It’s now clear - faulty site survey data can have serious consequences, impacting a solar project's operational and financial elements. Site surveys that are accurate and credible are essential to eliminating these risks and adding value to your customers.


To this end, accurate site surveys are crucial for the success of solar projects. They ensure optimal panel placement, optimized generation potential estimation and better budgeting, preventing issues with sizing and designing the systems.

So, the next time you're diving into a solar project, keep this in mind: the precision of your site survey data isn't just important—it’s the bedrock of your success. Don’t just aim to get it right; aim to make it perfect. Remember, while the sun generously provides its energy for free, efficiently harnessing it requires diligence and precision from the very beginning.