Third-party researchers PV Evolution Labs (PVEL) and National Renewable Energy Laboratory (NREL) put OpenSolar, a free solar design and sales platform, to the test, validating the accuracy of its solar design tool. The assessments include the following processes and findings.
Shading. OpenSolar asked NREL, which has been benchmarking shading accuracy of solar design tools for years, to assess the company’s 3D design tool. NREL compared the shading estimates provided by OpenSolar’s remote 3D tool with assessments made on the same roof using a SunEye, the world’s leading hand-held electronic shade measurement tool for on-site assessment. NREL found the accuracy of OpenSolar estimates to be best-in-class.
- OpenSolar’s assessment of Sun Access Values was accurate to within +/- 3%
- The current US market leader was only found to be accurate to within +/- 5%
Site Assessment. OpenSolar engaged PVEL to assess the accuracy of its system-generated site models. PVEL took measurements both in the field and in OpenSolar across a wide range of differently shaped and sized roofs. PVEL found the accuracy of OpenSolar’s models to be best-in-class.
- OpenSolar’s assessment of scale was accurate to within 1 ⅓ feet 100% of the time (no other tool provides as narrow a tolerance)
- OpenSolar’s assessment of pitch was accurate to within 4 degrees over 97% of the time (no other tool provides as narrow a tolerance OR such high compliance)
Energy Modeling. OpenSolar’s energy modeling (the conversion of key inputs, including pitch azimuth and shading into the key output: production) is based on NREL’s most advanced System Advisor Model (SAM). The company engaged with PVEL to validate the integrity of OpenSolar’s implementation of SAM, when comparing it to industry standard energy modeling tools like PVsyst or standalone implementations of NREL’s SAM. PVEL found:
- OpenSolar’s energy modeling is consistent with standard engineering practices
- OpenSolar’s production figures are within 0.0%-0.2% of standalone SAM estimates
- OpenSolar’s production figures are within 0.1%-1.9% of PVsyst estimates
“Our assessment of OpenSolar’s software confirms that its implementation of the SAM energy production model engine is accurate and in line with industry standards for residential and commercial projects and its 3D ray tracing calculations of beam shading are as good or better than other available products,” said Ryan Desharnais, Chief Technical Officer of PV Evolution Labs (PVEL). “We also sent measurement teams to a wide range of residential rooftops and verified the accuracy of OpenSolar’s physical site assessments. When taken together, these findings demonstrate that OpenSolar can produce high-quality energy generation estimates for solar projects.”
Combined with other key features of OpenSolar’s free-to-use platform, including access to a range of state-of-the-art hardware, a portfolio of competitive solar financing options, and on-demand customized permitting proposals, the company’s pitch is enabling solar installers to convert more prospects into booked sales while saving time and eliminating the costly licensing fees attached to other solar design and sales platforms.
For more on how OpenSolar works, here is our first ever Pitch video, diving into the software.
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