SOLAR PROGRAMS Presented By Benjamin H. Jordan, P.E. 4/2016

Agenda Current Distributed Generation Installations New Solar Programs Preparing for High Solar Penetration Summary

Current Solar installations Transmission (138kV) Solar 41 MW Distribution (34.5kV, 13.2kV) 54 MW Methane (34.5kV,13.2kV) 21 MW Rooftop Solar 19 MW Residential solar installations rate 62/month Commercial solar installations rate 4/month Residential 1900+ Commercial 250+ Estimated 22,000 homes powered

OCI – ALAMO1 OCI Alamo 1 Solar power plant modeled as a single 41 MW generator on the 138 kV transmission system Results of the Power Flow, Short-Circuit, and Transient Stability studies indicate that no additional system improvements were needed To meet ERCOT reactive power requirement, OCI added: 4 - 2.5 Mvar capacitors and 2 - 5 Mvar reactors

utility scale DG

Methane - Tessman Road

Solar 2015

Solar programs

Solar programs

roofless program Roofless Solar – Clean Energy Collective - 1MW tracking site Purchase Power Agreement Executed Site feasibility study complete Site expected to be on line 4th Qtr. 2016 Currently have 300kW reserved Panels are approximately 107.5 Watt panels 11,280 modules

roofless program

Solar host sa Program SolarHostSA- Starting at 1MW potentially up to 5MW New process evaluation for the program initiated Initiated a preliminary desk top review requirement Program is intended be spread over the service territory and avoid clustering Incorporated inverter functionality evaluation into the program

Solar host sa schedule SolarHostSA- Starting at 1MW The systems will be split in ½, 500kW Residential and 500kW Commercial Residential installs will be approximately 420 with an average system size of 6kW. Commercial installs will e approximately 25 with an average size of 100kW. Expected completion 12/2016

Inverter requirements The Smart inverter shall have the ability to receive firmware updates over the air The smart inverter shall have the ability to receive autonomous setting updates over the air Smart Inverter shall be able to support cellular and RF communication Functionality will need to be IEEE 1547 approved before it can be enabled in the smart inverters All functionality requires UL 1741 certification prior to being enabled on the smart Inverters

Inverter functionality Inverter Use Cases Anti-Islanding – Pending UL 1741 certification and amended IEEE 1547 approved Soft-Start Reconnection – ramping algorithm Low/High Voltage Ride Through – Pending California Rule 21, UL certification, and proposed amendment to IEC 1547 Low/High Frequency Ride Through – Pending California Rule 21, UL certification, and proposed amendment to IEC 1547 Volt/Var Mode – Pending California Rule 21 settings Reactive Power Control – Manufacturers are in beginning stages of testing Remote On/Off

Solar 2003-2010

Solar adoption Prediction

Future solar preparation Evaluate inverter control and communication methods Test inverter grouping methods from smart inverter deployment Inverter functionality review Stay in tune with the industry changes Solar cluster evaluations Monitoring solar penetration levels per phase Setting solar penetration levels that trigger studies AMI data aggregation Improve solar modeling

summary New analysis methods, tools and data will be required as our industry evolves and solar becomes more prevalent. Solar program expansion requires early involvement and preparation CPS Energy will continue to operate the distribution system efficiently, safely and reliably.

Questions?

Manager Distribution Planning Thank You For Your Time Contact Information Benjamin H. Jordan, P.E. Manager Distribution Planning 210-353-4493 210-259-9918 bhjordan@cpsenergy.com