Joshua Weiner, NABCEP Expert Witness
Curriculum Vitae


Contact this Expert Witness

  • Company: SepiSolar, Inc
  • Phone: 510.940.9750
  • Cell: 510.219.0267
  • Website:

Specialties & Experience of this Expert Witness

General Specialties:

Energy and Engineering

Keywords/Search Terms:

Solar,PV,Photovoltaics,Energy,Batteries,Construction,Electric Utility,Intellectual Property,Patent,Project Development,Electrical Engineering,Asset Management,Contracts,Electricity,Generation,Renewable Energy,Solar Energy,Solar Power,Solar Installation


Bachelor of Science, University of California Berkeley; Solar PV Certification, North American Board of Certified Practitioners

Years in Practice:


Number of Times Deposed/Testified in Last 4 Yrs:


Additional Information

Professional Expertise: As a solar PV expert witness, Weiner brings knowledge of law, policy, technology, contracts, finance, permits and entitlements, project development and construction, data acquisition and analysis that commonly apply to renewable energy and distributed energy projects. Specific areas of expertise, listed below, include energy technologies, markets, policy, finance, project development, planning and execution, project management, and codes and standards. Weiner is adept at unpacking complex topics into simple language that all parties can understand. Since 2007, Weiner is a certified member of the North American Board of Certified Energy Practitioners (NABCEP) in good standing. Weiner has also taught advanced solar system design and project management at UC Berkeley. Areas of Expertise: Energy Technologies Solar Batteries & Energy Storage Microgrids Markets Utility-Scale Commercial & Industrial Agricultural Residential Policy Tariff Rates Net Energy Metering (NEM) Interconnection Agreements Finance Incentive Programs & Structures Financing Programs & Structures Project Development Performance Modeling & Simulation Financial Modeling Contract Structures Ownership Models Project Planning & Execution Construction Management Sales Proposals, Pro Formas & Cash Flow Statements Technical Design Project Engineering Owner’s Engineering Independent Engineering System Design & Architecture Control Strategies & Microgrid Operations Project Management Technology Due Diligence Product & Vendor Selection Product Warranties, Guarantees & Liabilities Operations & Maintenance Data Acquisition & Monitoring Codes & Standards Health & Safety National Electrical Code UL Municipal Permits Industry Codes & Standards Solar Rights Act Expert Witness experience: In addition to consulting for NEXTracker, NRG Home Solar, and Green Charge Networks (now, ENGIE Storage), the below is a summary of Weiner’s expert witness experience. * Reviewed disputes and claims between project owners and Engineering, Procurement, and Construction (EPC) design-build companies involving contract, project, and construction documents as well as monitoring and performance data * Performed discovery and analysis (financial, technical, regulatory) to identify complex issues, then translating and articulating them in relatively simple terms * Performed project site visits and inspections to verify and analyze system health, performance, construction defects, regulatory compliance, contractual compliance, and utility interconnection compliance Professional Experience: Weiner’s professional experience includes engineering and design for: 1,000+ residential systems (5+ MW overall) 200+ commercial, industrial, agricultural systems (50+ MW overall) 12+ utility-scale systems (70+ MW overall) 15+ utility-interactive energy storage systems (8+ MWh overall)