Photovoltaic Systems Engineering Session 26 SEC598F17 Photovoltaic Systems Engineering Session 26 Residential PV System Case Study Design, Financing, Permitting November 21, 2017

Session 26 - Value to class members A case study to compare and contrast the “textbook” and actual design, operation, and analysis of a residential grid-tied PV system Design process Permitting and construction Operation Life Cycle Costing Payback Analysis

Grid-Tied PV Systems – The Design Process Design Steps in a Residential Scale System Examination of site and estimation of performance Securing financing Carrying out PV system engineering and design Securing relevant permits Construction Inspection Connection to the grid Performance monitoring

Grid-Tied PV Systems – The Design Process Design Goals in any Residential Scale System Meeting expected (or modeled) performance Engineering professionalism Reliable performance Standards and Codes Safe operation Architectural aesthetics Building and Zoning

Grid-Tied PV Systems – The Design Process Step 1 - Examination of site and estimation of performance Inspection of roof and yards Evaluation of obstacles, shading, and structures Examining the solar resource

Step 1 - Examination of site and estimation of performance Inspection of roof and yards

Step 1 - Examination of site and estimation of performance Inspection of roof and yards

Step 1 - Examination of site and estimation of performance South vs West

Step 1 - Examination of site and estimation of performance ASU Parking Structure

Step 1 - Examination of site and estimation of performance PV array sizing and module selection 14 modules: 7 x 2 array

Step 3 - Carrying out PV system engineering and design “Power Pergola”

Grid-Tied PV Systems – The Design Process Step 2 – Agreement with Builder/Installer Cash Purchase Contract with Sky Renewable Energy, Phoenix Homeowner will build the raised platform for the solar modules Sky will purchase the modules, inverters, BOS, and install theses components on the pergola Sky will produce and deliver to APS and the City of Phoenix the required electrical drawings

Grid-Tied PV Systems – The Design Process Step 3 - Carrying out PV system engineering and design Evaluation of space availability, solar availability, and electrical consumption PV array sizing Module selection Inverter selection Balance of system

Step 3 - Carrying out PV system engineering and design Evaluation of electrical consumption Average monthly baseline usage – 160kWh

Step 3 - Carrying out PV system engineering and design Comparison of electrical consumption to solar electricity production Annual total electrical usage – 5300 kWH Annual total solar electricity production – 6300 kWh PVWatts - 3500 W system, 18o tilt Ratio: 6300/5300 = 1.19; By APS regulations, the ratio cannot exceed 1.25

Step 3 - Carrying out PV system engineering and design Inverter Selection Option 1: A 4kW string inverter Option 2: Microinverters installed directly on the backs of the PV modules

Grid-Tied PV Systems – The Design Process Step 4 – Securing relevant permits Special overlay districts Architectural considerations Zoning ordinances Setbacks, elevations, materials Building permits Construction practices; electrical enclosures, wiring, components Engineering approvals Mechanical considerations Utility agreements Connection arrangements; net metering rules; electrical signal quality

Step 4 – Securing relevant permits - HPO

Grid-Tied PV Systems – The Design Process Step 4 – Securing relevant permits Special overlay districts Architectural considerations Zoning ordinances Setbacks, elevations, materials Building permits Construction practices; electrical enclosures, wiring, components Engineering approvals Mechanical considerations Utility agreements Connection arrangements; net metering rules; electrical signal quality

Step 4 – Securing relevant permits – P&Z

Grid-Tied PV Systems – The Design Process Step 4 – Securing relevant permits Special overlay districts Architectural considerations Zoning ordinances Setbacks, elevations, materials Building permits Construction practices; electrical enclosures, wiring, components Engineering approvals Mechanical considerations Utility agreements Connection arrangements; net metering rules; electrical signal quality

Step 4 – Securing relevant permits – P&Z