Update on CAISO / PacifiCorp Energy Imbalance Market Presentation to WECC Market Interface Committee March 25, 2014 Jim Price, Senior Advisor, Market Development & Analysis, CAISO

What is the Energy Imbalance Market? Leverages existing CAISO market, for financial benefits at low cost & with low risk –Starting from forecasted load and balanced generation, EIM’s security constrained unit commitment and economic dispatch: Automatically dispatch least cost resources to solve imbalances, Avoid congestion. Enhances reliability with improved situational awareness Captures geographical diversity of load and resources Potentially reduces flexible reserve requirements Provides easy entry/exit for EIM participation –No critical mass – each participant enters when they are ready –New participants pay their way through a front end charge based on size, and ongoing charges based on participation. Page 2

Page 3 Scale of EIM in the West is growing PacifiCorp: FERC approved implementation agreement June million customers 9,500 MW peak demand 10,600 MW generating capacity NV Energy: announced intent Nov million customers 8,148 MW peak demand 5,815 MW generating capacity CAISO: existing market 11.4 million customers 50,280 MW peak demand 58,246 MW generating capacity CAISO is working with other interested parties

EIM implementation and stakeholder processes are in progress Page 4 Implementation agreement System testing market simulation FERC review Implementation work CAISO filed 2/28/2014, PacifiCorp filed 3/25/2014 FERC review Go live 10/1/2014 tariff language Process Merger CAISO Board authorization 11/8/2013 FERC acceptance Filing 4/30/2013 CAISO Board authorization 3/20/2013 FERC acceptance 6/28/2013 CAISO & PacifiCorp EIM stakeholder processes CAISO Stakeholder meetings: 4/11/2013 – Folsom 6/6/2013 – Folsom 7/9/2013 – Phoenix 8/20/2013 – Portland 9/30/2013 – Folsom Market simulation testing begins 7/8/2014

Guiding objectives for governance drive toward a long-term independent EIM Independent EIM structure Page 5 Stakeholder Transition Committee Nominee list posted 3/6/2014, Board selects committee 5/28-29 Roles: advise on EIM matters, propose independent EIM structure Sectors: investor owned utilities, publicly owned utilities, generators and marketers, alternative energy providers, EIM participants, government agencies, public interest entities Open meetings, CAISO staff support, no compensation Prompt & direct input Adaptable structure Promote successful implementation STEP 1 STEP 2

More information is available Briefings to MIC 7/18/2013 & 10/24/2013, to UFAS 1/8/2014 (see WECC web site) Computer based training: “Introduction to the Energy Imbalance Market” – CAISO EIM stakeholder process – –Includes proposals, benefit assessments, tariff development, etc. PacifiCorp EIM information – –Includes fact sheets, memorandum of understanding, link to OASIS for stakeholder process, etc. Page 6