New website provides automated engineering stamps for residential solar


Castillo Engineering, a solar installation company ranging from residential to mid-size utility-scale projects, announced it has launched to provide automated residential solar letters.

The company said it is the first in the U.S. to launch fully automated structural letters, professional engineer (PE) stamps and post-installation letters. It is compatible with all 50 U.S. states and some overseas markets.

The website utilizes a range of application programming interface (API) integrations, which the company said enables a 99% accuracy to rate to the documentation. It said that the website will further leverage artificial intelligence to speed the processing of solar letters and PE stamps. Currently, the website has the capacity to generate over 100,000 solar letters per month, said the company.

“The Solar Letters platform is a game-changer for LGCY,” said Ben Ogden, manager, design and engineering, LGCY Power. “It has simplified the structural and electrical engineering process and increased our turn times on stamped projects.”

Soft costs, permitting, and inefficient documentation processes are a persistent issue in the U.S. residential solar market. Soft costs represent any cost not tied directly to the cost of hardware itself. In the U.S., soft costs represent 65% of the project, said the Department of Energy (DOE). Shawn Rumery, senior director of research at SEIA, said since 2014, residential system costs have come down 25%, but soft costs have dropped only 15%. Customer acquisition and overhead costs have risen 31% in the same time period, Rumery said.

Many installation firms still use simple document or spreadsheet-based processes to file PE stamps and other letters.

“All of these methods have been tested and proven to be highly error prone, particularly with non-degreed engineers manually completing forty to fifty letters per day,” said SolarLetters.

The SolarLetters website incorporates data from over 40,000 authorities having jurisdiction (AHJ), and the company said it guarantees a 99% AHJ approval rate.

The company issues a full credit for any document that receives AHJ rejection and offers volume discounts through a Permit Partner Program. It also offers price matching to the lowest quote for its solar letter service.

“We are very excited to launch in response to the high demand for residential solar letters and PE stamps we are seeing globally,” said Christopher Castillo, chief executive officer of Solar Letters. “We look forward to providing the same elite customer service experience for clients as we do through Castillo Engineering. Helping solar installers drastically cut soft costs and mitigate project risks are necessary to ultimately enable solar energy to proliferate across the globe.”

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