Kevin Joyce, Manager Grid Engineering Solutions

March 15, 2016

SunSpec Alliance Annual Meeting Case Study – Smart Energy Homes

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Networked and aggregated Distributed Energy Resources, (DERs) including Smart Energy Homes, are demonstrating value to the grid. § SolarCity is working with SunSpec on a landmark project to

develop and demonstrate a path to increased grid value for DERs and Smart Energy Homes.

§ Grid services from aggregated DERs are being demonstrated today ‒ Smart inverters providing voltage support ‒  Intelligently coordinated DERs providing dynamic capacity

Executive Summary

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•  Objective •  Develop and demonstrate a roadmap for cost-effective smart inverters

to enhance reliability, increase DER integration and enable additional DER services.

•  Scope •  Phase 1: Lab testing •  Phase 2: Field deployment

•  50 homes installation •  Distribution use cases •  Wholesale use cases

•  Phase 3: Market assessment •  Benefits

•  Distribution Cost Avoidance •  Reduced installation costs •  Improved asset flexibility •  Decreased GHG emissions

CEC PON 14-303 - Scope

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Distributed Energy Resource Aggregation Utilize portfolios of distributed energy resources to provide grid services

Demand Management

Distribution Capacity

Voltage Support

Reactive Power

Support

Smart Energy Home

Aggregated DER Portfolios Grid Services

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Feeder Voltage Profile

Field Results: Voltage Support Solar with smart inverters eliminated need for line regulator to solve pre-existing high voltage condition

Thu 12:0

Deployment included 275 inverters and 5MW of PV

Voltage Pre-Solar Voltage Post-Solar

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Field Results: Volt / VAR Regulation Smart inverters actively manage voltage

700kW of smart inverters providing Volt/VAR control

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Distributed resources can reduce peak loads on distribution system circuits

 600    

 700    

 800    

 900    

 1,000    

 1,100    

 1,200    

 1,300    

 1,400    

 1,500    

 1,600    

1   2   3   4   5   6   7   8   9   10   11   12   13   14   15   16   17   18   19   20   21   22   23   24  

MW  

Hour  of  Day  

HVAC  Load  Reduc9on  Storage  Discharge  PV  2022  Load  

Peak  Shaving  

•  SolarCity simulated results for a distribution circuit in Southern California Edison territory

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Field Results: Dynamic Capacity 190 inverters and 1.8MW PV

Configurable Threshold

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Field Results: Dynamic Load Control 22 electric water heaters deployed to absorb PV output

Before Load Control After Load Control

PV production is always lower than gross load, ensuring no net export beyond point of common coupling

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Smart Energy Homes are a commercial product

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Thank you