Integrating Solar PV and Storage in Smart Grids

1. Integrating Solar PV and Storage in Smart Grids Brad Roberts ESA Executive Director Power Quality Systems Director S&C Electric Company SunSpec Alliance Member’s Summit January 31, 2012 Las Vegas, NV

2. The Grid Connected Energy Storage Market is Large….. Estimated Global Installed Capacity of Energy Storage Source: StrateGen Consulting, LLC research; thermal storage installed and announced capacity estimated by Ice Energy and Calmac. Note: Estimates include thermal energy storage for cooling only. Figures current as of April, 2010.

3. Significant Events in the Storage Marketplace • USA > AWEA/ESA Joint Statement on the benefits of wind and storage for a flexible grid > Formation of the ESA Advocacy Council to form a unified voice for storage at the Federal level > New FERC Order 755 on “pay for performance” on ancillary services > Potential Federal ITC tax legislation for storage project investments > New battery plants coming on line in the US with lower battery costs • Europe > Formation of EASE as a voice for storage at the EU > Expanding number of storage demonstration projects

4. Hierarchy of Grid-Purposed Energy Storage Large Central Units 100s of MW Substation Batteries 10s of MW Storage at Grid Edge 10s of kW Graphics adapted from an EPRI Presentation by Joe Hughes

5. How do Current Markets Reward the Unique Capabilities of Energy Storage? Market Reward for Storage Owner Unique Capability Unique Benefit System Fuel Savings related to time of use Energy Price Arbitrage Time Shifting System Emissions Savings related to time of use Mostly None System Fuel Savings related to ramping Fuel cost impact usually included Regulation Price Speed of Response System Emissions Savings related to ramping None Reduction in necessary Regulation Capacity FERC Order 755 requires “Pay for Performance” Smooth Fluctuation of Wind and Solar Power None – except Hawaii

6. Resource Attributes

7. Solar and Wind Power is Typically Intermittent

8. Renewable Energy Integration Photovoltaic (PV) or Wind Power Smoothing ~ ~ Required Output Traditional Generation Energy Storage can smooth the abrupt changes of renewable generation to the acceptable limit the grid can handle.

9. Integrating Solar PV and Storage in Smart Grids At all levels of the grid opportunities exist for integration of solar PV and storage. • For large-scale applications, typically 1.0 MW and large, storage can smooth and shift the solar power to optimize the response to the load. • At the residential or small commercial level, the challenge can be greater based on the penetration level on specific feeders. • Many utility demonstration projects are underway to refine the performance of distribution circuits.

10. Public Service of New Mexico ARRA Project for Solar Integration with Storage

11. PNM Project to Demonstrate Smoothing and Load Shifting of Solar Energy • Project utilizes two advanced lead-acid technologies from East Penn Manufacturing • Advanced lead acid for load shifting the solar peak to allow for dispatching at the highest load peak • UltraBattery for smoothing of the solar output to demonstrate the high cycling capability of the technology • Battery Ratings: Advanced Lead Acid…..250 kW for 4 hours UltraBattery…………….500 kW for 30 minutes

12. PNM Project Goals • Test the battery technology in a renewables integration application • Measure performance and cycle life over time in a real world application • Refine the control system to optimize the utilization of the battery to maximize daily dispatch of renewable solar energy on the grid • There is an additional installation of this battery chemistry combination in Australia

13. Kansas Hybrid Wind Solar & Storage Project Overview Use the SPP methodology to establish average capacity credit for the summer months: • A stand-alone solar facility yields 50% more capacity than wind • A hybrid facility yields 80% more capacity credit than one wind and one solar stand-alone facility • A hybrid facility with 6 hours of storage yields 160% more capacity credit than the stand-alone wind and solar facilities • Values based on a hybrid facility of 100 MWs of wind, 20 MWs of solar and 15 MWs of storage for 6 hours. These are the optimum values for maximum benefit

14. Solar & Load in Summer • Solar production aligns well with the demand profile. • Average solar profile does not reflect the minute-to-minute variability that can result from passing clouds. • There is less variability in solar production than wind production.

15. Project Benefits • Wind Power Benefits: • Increases amount of wind power available during peak load periods • Avoids curtailment of wind allowing storage of excess capacity typically at night • Reduces variability by controlling the rate of change in output power level • Reduces “extreme ramp events” • Self-supply reserves • Increased correlation with load • Solar Power Benefits: • Smooth rapid power fluctuations caused by passing clouds • Allows solar power output to be shifted to match afternoon • load peaks (typically 2-3 hours)

16. Sample of Solar/Storage projects under way in the U.S. • Duke Energy - Rankin Substation - Sodium Nickel Chloride for PV smoothing • Duke Energy – Marshall Substation • Lithium Ion for Peak Shaving • Chevron Santa Rita Jail Micro grid project • Lithium Ion for PV smoothing and Load shifting • San Diego Gas and Electric • Lithium Ion for PV Smoothing • PNM ARRA Funded Solar Smoothing and Load Shift • Advanced lead acid batteries

17. CES – Community Energy Storage d Distributed Energy Management Controller (DEM) Communications CES Units …

18. Wide-Scale Deployment of CES DMS – Situational Awareness Fleet Management – Set and Forget Substation 3 Substation2 Substation1 Feeders & Communication Infrastructure Fleet 1 Fleet 2 Fleet 3

19. Typical CES Installation

20. Developing Energy Storage Markets • Developing the market mechanisms to allow storage is the key to success • Changing 100 years of electrical system market design doesn’t happen overnight

21. Questions?