1

CPUC Energy Storage WorkshopEnergy Storage Procurement Framework and Design Program

& Action Plan of the California Energy Storage Roadmap

Energy Division Workshop in accordance with Track 1 of Proceeding: R.15-03-011

Comments by Dustin Mulvaney, Ph.D. Principal, EcoShift Consulting,

Associate Professor, San Jose State University, on behalf of Sierra Club

July 28, 2015

2

Consistent Evaluation Protocol (CEP)

Goals & objectives of storage roadmap• Reduce greenhouse gas emissions• Integrate renewables• Grid optimizationCEP guiding principles• Transparency, public access to information• Public accountability

3

Unresolved issues include quantification of benefits

• GHG emissions reduction• Avoided T&D• Other project level benefits• System/portfolio level benefits

GHG emissions reductions are not adequately incorporated.

4

CEP Refinement

CEP should quantify• 8. Intermittent resource integration: wind

(ramp / voltage support) • 9. Intermittent resource integration:

photovoltaic (time shift, voltage sag, rapid demand support)

• 10. Supply firming• 11. Peak shaving

5

Storage projects charged with natural gas fired electricity do not reduce GHG emissions

Adapted from the NREL publication: Denholm, Paul, and Gerald L Kulcinski. 2004. “Life Cycle Energy Requirements and Greenhouse Gas Emissions From Large Scale Energy Storage Systems.” Energy Conversion and Management 45, no. 13: 2153–72. doi:10.1016/j.enconman.2003.10.014.

RenewablesCombined Cycle

Natural Gas

Coal

CC Natural Gas

SC Natural Gas

Single Cycle Natural Gas Coal

Compressed airPumped hydroVanadium Redux BatterySodium Flow Battery