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Top-tier engineering & designs for community solar projects

Castillo Engineering is proud to support community solar projects as it allows for equal access to the economic and environmental benefits of solar energy generation. Castillo Engineering has grown to become the leading design and engineering firm for high-quality community solar projects as a result of the firm’s 25+ years of solar engineering experience, minimal bill of material designs, fast turnaround times, and strong industry relationships.

Schedule a meeting with one of our solar and storage experts

First-in-class project management of large-scale engineering 

Castillo Engineering is the only large-scale solar and storage design and engineering firm that is led by its Project Management Office (PMO). Certified by the Project Management Institute (PMI), all of the company’s Project Managers are highly trained and experienced in key project management subjects, including planning, execution, monitoring and controlling, communications, as well as cost, risk, quality, time and procurement management. The company’s expertise in project management ensures your projects are always completed on time and on budget and that you are apprised of all project updates.

Exceptional communication with all stakeholders 

Castillo Engineering delivers an extremely organized and collaborative partnership with all stakeholders to ensure the efficient and streamlined completion of each project. The company’s Project Managers are certified by the Project Management Institute (PMI) and deeply understand the value of clear and regular communication with all parties involved in a project. 

Track record of scaling while maintaining quality 

Castillo Engineering continues to be selected by the nation’s top EPCs, developers and utilities due in large part to its ability to scale without compromising project quality. The company has robust and vetted internal processes in place to ensure it continues to only hire staff that align with the company’s mission, vision and values. Once hired, staff are required to complete the company’s training program to ensure new team members have the skills and resources needed to maintain the same level of quality and excellence found at Castillo Engineering. 

Maintain deadlines

With over 25 years of experience in solar and storage design and engineering, Castillo Engineering understands that completing your project on time and on budget is critical. You can rely on Castillo Engineering and its Project Management Office (PMO) to meet all project deadlines, removing a major element of complexity from your project. 

Maximizing project value through innovation and practicality

Castillo Engineering approaches every project uniquely and as if it were the owner and EPC. The company does not take a conservative approach, however, it also does not take an aggressive approach to its design and calculations. Castillo Engineering takes a practical approach. The company’s team members ask themselves: if I owned this project, what decision would I make? The company is not afraid to try a new approach or technique, because it strips down the concepts to the practicality of physics. When Castillo Engineering puts its stamp on its plan sets, you know the company has done everything it can to ensure safety, cost savings, and longevity. The company will never say the word ‘no’ to a unique or requested design question. It will always take time to find a solution that meets your needs.



The nation’s leading EPCs, Developers and Utilities continue to rely on Castillo Engineering’s market leading fast turnaround times, minimal bill of material designs and utility interconnection success to shorten their project duration and increasing profitability.

Castillo Engineering continues to maintain repeat client partners due to the fact that the firm not only completes projects efficiently and cost effectively, but because they have your long-term production interests in mind.


  • Equipment pad design

    • Review equipment spec sheets

    • Review soils report

    • Concrete pad design   

    • Skid foundation design

  • Cable routing mounting systems, including CAB

  • Roof structure review and calculations 

  • Snow drift and unbalanced loading

  • Ponding instability evaluations 

  • Wind and seismic design

  • Carport foundation design


  • Strong and consistent communication and coordination with the field teams to ensure they have the information they need to progress on the project

  • Rapid responses to Requests for Information

  • Construction site visits to review the installation in light of the design and to provide support as needed to the installation team 

  • Timely equipment submittal reviews


Preliminary Civil Engineering packages include:

  • Grading optimization

  • Pile length optimization 

  • Racking modeling & recommendation

  • Preliminary civil site plan design optimization

  • Permitting support 

  • Preliminary array design optimization

Civil Engineering IFC packages include:

  • Solar array 

  • Parcel boundaries 

  • Easements

  • Right of Way

  • Setbacks to include:

    • Wetlands

    • Fence line

    • Tree line

  • Access, turnaround & roadway(s)

  • Equipment staging area

  • Schematic layout of electrical equipment

  • Grading design shall include:

    • Array grading

    • Basin or pond grading

    • Equipment pad grading

    • Road grading

  • Stormwater Pollution Prevention Plan (SWPPP)

  • Incorporation of survey and topography


We are a project management-driven engineering firm. Our Project Management division, or  Project Management Office (PMO), consists of experienced Project Managers. All of our Project Managers are certified by the Project Management Institute (PMI), a globally recognized organization that sets standards and provides best practices in the field of project management. Every PMO team member has earned PMI’s designation as a Project Management Professional (PMP). They have all taken courses and been certified in key project management subjects, including planning, execution, monitoring and controlling, communications, as well as cost, risk, quality, time and procurement management.

Our Community Solar and Storage Construction Plans (IFCs) Include:

PV Array Design & Optimization

  • Array layout

  • Major equipment location 

  • Module stringing

  • Setbacks to include: 

    • Shading 

    • Equipment delivery pathways, laydowns, and turnarounds

    • O&M access and pathways

  • Integration of racking vendor’s drawings. 

  • Collaboration with appropriate engineering disciplines.


Our Energy Storage Construction Plans (IFCs) include Battery Energy Storage System (BESS):

  • Equipment specification 

  • System layout 

  • Interconnection method 

  • Single line diagram 

  • Feeder and branch circuit routing

  • Voltage drop and conductor sizing

Other BESS Services include: 

  • BESS System Sizing 

  • Owner’s Representative Site Observations 

  • Site Visits (Pre, During, Post Construction) 

  • Equipment Submittal Review 

  • Independent Engineer Review 

  • Interconnection Application Design & Support 

  • Equipment Pad Design



  • Point of interconnection 

  • Construction notes and specifications

  • Data and monitoring systems 

AC & DC Electrical Engineering (each):

  • ​Equipment specification

  • Single line diagram  

  • Circuit routing   

  • Voltage drop

  • Conductor sizing   

  • Grounding and bonding  

  • Short circuit study

  • Arc flash study 

  • Surge arrester specification


  • PV & BESS Power Studies

  • Cable thermal calculations

  • Overcurrent protection coordination

  • Ampacity Studies using CYMCAP and AmpCalc

  • DC and AC Arc-flash calculations

  • Load Flow and Reactive Power Studies

  • Grounding Studies using WinIGS and CDEGS

  • Short Circuit Studies

  • Transient Studies

  • Pre and Post Energization Harmonic Studies

  • Lightning Risk Assessments

  • Interconnection application support and modeling


From the initial stages of development through to project completion, we provide:

  • Site preparation and land development support

  • System architecture

  • 3D physical designs (e.g., elevations and general arrangement)

  • Control enclosure (Control Panel Layouts)

  • Relay, protection and control design

  • Equipment Specifications and Bill of Materials (BOM)

  • Power System Studies

  • Civil engineering

  • Structural engineering

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