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Project Description 1 South Lake Solar and Energy Storage Project PROJECT DESCRIPTION 1. INTRODUCTION The South Lake Solar and Energy Storage Project (referred to hereafter as the “Project”) is proposed by South Lake Solar, LLC (referred to hereafter as the “Applicant”) and includes solar generation, energy storage, and construction of associated ancillary facilities at a new solar energy facility in Fresno County, California. The Applicant proposes to construct and operate the Project on approximately 585 acres to produce approximately 180,000 megawatt-hours of renewable energy annually. The Project would be an up to 80- megawatt (MW) alternating current (AC) photovoltaic (PV) solar energy facility with associated on-site substation, inverters, fencing, roads, and supervisory control and data acquisition (SCADA) system. The proposed energy storage components would include an up to 80 MW AC maximum capacity energy storage (battery) system. The Project would also include a 70-kilovolt (kV) overhead generation tie line (gen-tie line), which would extend approximately 500 feet from the on-site substation to the adjacent existing Pacific Gas & Electric Company (PG&E) Five Points electrical substation located on the western side of South Lake Avenue. For purposes of environmental review under the California Environmental Quality Act (CEQA), based on the scope of the Project and the County’s understanding of the environmental resources and potential impacts to those resources, it is anticipated that preparation of an Environmental Impact Report (EIR) and Mitigation Monitoring and Reporting Program (MMRP) would be required. 1.1 PROJECT OBJECTIVES The Applicant’s primary objective is to generate renewable solar electricity utilizing proven technology, at a competitive cost, while minimizing environmental impact. Specific Project objectives include: Construct an up to 80 MW AC PV solar energy facility that would generate approximately 180,000 megawatt-hours of renewable energy annually, including the option for an additional up to 80 MW of energy storage, to satisfy anticipated power purchase agreement terms and facilitate progress toward achieving the State’s Renewable Portfolio Standards and Senate Bill 350 greenhouse gas (GHG) reduction goals; Generate and transmit electricity at a competitive rate; and Locate the proposed facility in close proximity to the existing PG&E electrical distribution system. 2. PROJECT LOCATION The Project site is located on approximately 585 acres of two parcels in the San Joaquin Valley of California, in southwestern Fresno County (Figure 1, Regional Map), approximately 30 miles southwest of the City of Fresno and 3.4 miles south–southwest of the unincorporated community of Five Points. The Project site encompasses a majority of Section 8, Township 18 South, Range 17 East, and the very western portion of Section 9, Township 18 South, Range 17 East, Mount Diablo Baseline and Meridian of the Westside and Harris Ranch, U.S. Geological Survey 7.5-minute topographic quadrangles at approximately latitude/longitude 36°22'43.96" N/120°8'50.93" W (Figure 2, Vicinity Map). The Project site is bordered to the north by West Paige Avenue and to the south by West Jeffrey Avenue, to the west by South Butte Avenue and to the east by South Lake Avenue. The proposed gen-tie line would extend Page | 1 South Lake Solar and Energy Storage Project Figure 1. Regional Map. Page | 2 South Lake Solar and Energy Storage Project Figure 2. Vicinity Map. Page | 3 South Lake Solar and Energy Storage Project approximately 500 feet east from the Project site to the existing PG&E Five Points electrical substation located adjacent to the Project site on the eastern side of South Lake Avenue. 3. PROJECT LAND USE AND ZONING CHARACTERISTICS The Project site consists of land designated as Agriculture in the Fresno County General Plan and zoned AE-20 (Exclusive Agricultural, 20-acre minimum parcel size) pursuant to the Ordinance Code of the County of Fresno, Zoning Map. The Project site and surrounding properties are primarily composed of tilled croplands, although the Project site is only dry farmed. An existing irrigation restriction applies to properties in the vicinity, including the Project site, which limits on site agricultural operations to dry farming. The site is adjacent to the Westside and Whitney Point solar projects, which recently completed construction. Single-family residences, farm supply businesses, and other agricultural properties are concentrated along State Route 145 and South Butte Avenue north and west of the site. 4. PROPOSED PROJECT The Unclassified Conditional Use Permit (UCUP) allows the County to consider special uses that may be essential or desirable, but which are not allowed as a matter of right within a zoning district. Certain uses of land or types of businesses specified in the Fresno County Zoning Ordinance require a UCUP application. PV solar power generation facilities may be permitted in any zoning district through the UCUP discretionary application process. The Project Applicant is seeking UCUP approvals to allow construction and operation of the Project on approximately 585 acres in the Exclusive Agricultural, 20-acre minimum parcel size zoning designation. 5. PROJECT COMPONENTS The Project consists of the following components: Solar energy generation system On-site substation Energy storage system Gen-tie line Ancillary facilities 5.1 SOLAR ENERGY GENERATION SYSTEM The Project includes up to an 80 MW solar power generating system. The approximately 585-acre site would house all structures, including solar panels, fixed-tilt or single-axis tracking support structures, inverters, SCADA, and interconnection facilities (on-site substation), all of which would be enclosed by a perimeter security fence. The proposed site plan is shown on Figure 3. Solar energy would be captured by PV panels mounted to a single-axis or fixed-tilt racking system (refer to Figure 3 for conceptual configuration of the arrays and Figure 4 for an elevation diagram illustrating the different tilt positions for a typical single-axis tilting array). The high-efficiency, commercially-available PV panels convert incoming sunlight to direct current (DC) electrical energy. The panels are arranged in series to effectively increase output voltage to approximately 1,500 volts. These series chains of panels are called “strings” in industry terms and provide the basic building block of power conversion in the solar array. The strings are combined in the solar field through an above- or below-ground DC collection system, and then further tied together at the inverter stations, where the energy is converted to AC and then stepped up to an intermediate voltage, typically 34.5 kV. The chosen PV panel would be either crystalline silicon or thin film and would be well suited for the environment due to their durability and reliability. Page | 4 South Lake Solar and Energy Storage Project Figure 3. Site Plan. Page | 5 South Lake Solar and Energy Storage Project Figure 4. Elevation Diagram for Typical Single-Axis Tilt Array. Page | 6 South Lake Solar and Energy Storage Project The racking system would be supported, when practical, by driven piers (piles) directly embedded into the ground, and would be parallel to the ground. Each rack would hold approximately 80 to 90 panels (depending on final configuration), and at its highest edge, would have a maximum height up to 12 feet above grade, depending on the dimensions of the chosen panel and racking technology. The minimum clearance from the lower edge of the panel to ground level would be approximately 18 to 24 inches, pending final design. The single-axis tracking system (if selected) would rotate slowly throughout the day at a range of +/- 60 degrees facing east to west to stay perpendicular to the incoming solar rays so that energy production would be optimized (refer to Figure 4 for an illustration of various array tilt positions for a typical single-axis tracking system). The inverter stations would be up to 12 feet in height and perform three critical functions for the solar facility: (1) collect DC power in a central location, (2) convert the DC power into AC power, and (3) convert low-voltage AC power to medium-voltage AC power. The inverter stations are typically open-air. The stations consist of DC collection equipment, utility-scale inverters, and a low- to medium-voltage transformer. The output power from the inverter stations is then fed to the AC collection system through an above- or below-ground collection system. This AC collection system would deliver the electricity to the on-site substation, where the voltage would be stepped up through a transformer to the interconnection voltage. 5.2 ON-SITE SUBSTATION The Project on-site substation would be the termination point of the collection system for 34.5 kV electricity. The output of the entire field would be passed through a final interconnection step-up transformer to convert it to the grid voltage at 70 kV. Additionally, the Project on-site substation would host the grid intertie safety equipment and switches required to interconnect to the high-voltage transmission system. The open-air, on-site substation would potentially be constructed on the eastern border of the solar array nearest to the PG&E Five Points substation located on the eastern side of South Lake Avenue. The footprint of the on-site substation would be approximately 150 feet by 150 feet. The Project on-site substation would consist of components up to 55 feet in height, and on-site feeders would be overhead lines constructed with 45-foot-tall and 60-foot-tall poles for the single and double circuits, respectively. 5.3 ENERGY STORAGE SYSTEM Adjacent to the on-site substation, an energy storage system is proposed to provide a maximum capacity of 80 MW. The energy storage batteries would be housed in a structure or container boxes and would be located on approximately 3 acres of the Project site.
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