Battery Energy Storage

Transcription

1 Battery Energy Storage Implications for Load Shapes and Forecasting April 28, 2017

2 TOPICS» What is Energy Storage» Storage Market, Costs, Regulatory Background» Behind the Meter (BTM) Battery Storage Where is it used? How is it used? Real world examples (California research)» How to analyze storage? Simulations vs. Data» Where is the market going? 2

3 WHAT IS ENERGY STORAGE?» The capture of energy produced at one time for use at a later time. Pumped Hydro Compressed Air Batteries 3

4 BATTERY ENERGY STORAGE Dominating technologies» Dominated by Lithium Ion Batteries followed by flow batteries 4

5 BATTERY ENERGY STORAGE Size categories» Transmission connected» Distribution Connected» Behind the Meter Source: Rocky Mountain Institute 5

6 WHY STORAGE NOW? Falling Costs Tesla Gigafactory Rising Demand Charges Now make up 50% or more of commercial bills More Intermittent Renewables Balance variability Offer the ability to line up peaks Reliability Power Outages Hurricane Sandy 6

7 BATTERY ENERGY STORAGE Grid Scale Source: Greentech Media» Catastrophic leak Oct at Aliso Canyon natural gas storage facility threatened to cause power outages across Southern CA» 70 MW of energy storage deployed in 6 months 7

8 BATTERY ENERGY STORAGE Behind the Meter C&I 8

9 BATTERY ENERGY STORAGE Behind the Meter Residential 9

10 U.S. ANNUAL DEPLOYMENT FORECAST Advanced Energy Storage, (MW) Source: Greentech Media 10

11 CAPITAL COSTS Lithium Ion BTM Source: Itron DG Cost Effectiveness Model» Tesla data point remains unproven -claims to be ~½ price of prior versions 11

12 BTM STORAGE REGULATORY DECISIONS Regulatory Background» California Self-Generation Incentive Program modified to included standalone storage in 2011 Most recently program funding doubled to $166 million per year (85% storage allocation)» California Public Utilities Commission (CPUC) mandated 1,325 Megawatts of storage by 2024» Hawaii and Australia reformed tariffs to encourage selfconsumption» New York, Massachusetts, and New Jersey provide incentives for energy storage 12

13 CALIFORNIA BTM RESEARCH Self-Generation Incentive Program

14 HOW IS BTM STORAGE BEING USED IN CA? What we know so far» Backup Power» PV Self-Consumption» Demand Charge Reduction» TOU Bill Management» Aggregated Demand Response 14

15 WHERE IS BTM STORAGE BEING DEPLOYED? What we know so far Note: SGIP is ~18% of estimated U.S. annual deployment at

16 WHERE IS BTM STORAGE BEING DEPLOYED? What we know so far Non-Res 16

17 SGIP DATA ANALYSIS During 2015» Collected interval performance data from storage systems, merged with AMI data Aggregated results: 2015 Individual case studies: 2016» Focused on customer energy and peak demand Coincident and non-coincident demand» Residential and Non-Residential PBI = Large C&I 17

18 NON-RESIDENTIAL (C&I) STORAGE PROJECTS

19 ENERGY IMPACT Distribution of 15-Minute kwh Charge/Discharge 15-Min Charge / Discharge kwh Most (+80%) of the time systems are idle Charge/Discharge patterns are fairly symmetrical, so annual energy impact is negligible 19

20 METRICS: ROUND-TRIP EFFICIENCY Non-residential AES projects, RTE = total kwh of discharge from the storage project total kwh of charge Program Requirement: 63.5% annual RTE 20

21 CASE STUDY 1 CITY GOV. BUILDING 2016 Data, Narrow Peak Calculated Load AMI Load Storage Discharge (+) / Charge (-) 21

22 CASE STUDY 2 CITY GOV. BUILDING 2016 Data, Wide Peak Calculated Load AMI Load Storage Discharge (+) / Charge (-) 22

23 CASE STUDY 3 CITY GOV. BUILDING 2016 Data, DR Example Calculated Load AMI Load Storage Discharge (+) / Charge (-) 23

24 CASE STUDY 4 CITY GOV. BUILDING 2016 Data, Another DR Example Calculated Load AMI Load Storage Discharge (+) / Charge (-) 24

25 CASE STUDY 5 GROCERY STORE / EV CHG Data, Idle Calculated Load AMI Load Storage Discharge (+) / Charge (-) 25

26 SMALL C&I PROJECTS (NON-PBI) Charging not coordinated Total kwh of Discharge (Charge) per kw Rebated Capacity, Non-PBI Projects 2015 H o u r Month

27 LARGE C&I PROJECTS (PBI) Large C&I (PBI) Projects Charge Overnight, Discharge in Evening Total kwh of Discharge (Charge) per kw Rebated Capacity, PBI Projects 2015 H o u r Charging overnight, when energy is cheap, discharging in evening, when demand is highest and energy most expensive 27

28 LARGE C&I (PBI) PEAK DEMAND REDUCTION Average Non-Coincident Peak Load Reduction by Month, per Customer (PG&E) Significant increase in non-coincident peak load reduction during summer months, compared to the rest of the year PBI projects saved an average of ~$0.8 per kw rebated storage capacity in demand charges 28

29 2015 COINCIDENT PEAK IMPACTS Only Large C&I (PBI) Project Contributed to Coincident Peak Demand Reduction 29

30 Net Discharge (MWh) Tons CO2 per MWh Net Discharge (MWh) Tons CO2 per MWh NON-RESIDENTIAL AES CO 2 IMPACTS Alignment of grid emissions with charge/discharge Large C&I» Generally discharging during higher marginal emission hours Marginal Emissions Compared to Aggregate Discharge (Charge), PBI Projects, Summer Hour of Day Winter Hour of Day Small C&I» With low efficiency, net charging in all hours Net Discharge Marginal Emissions Net Discharge Marginal Emissions Marginal Emissions Compared to Aggregate Discharge (Charge), No-residential, Non-PBI Projects, 2015 Summer Winter Hour of Day Hour of Day Net Discharge Marginal Emissions Net Discharge Marginal Emissions 30

31 NON-RESIDENTIAL CO 2 IMPACTS Population of estimates» Net increase in GHG emissions for both large and small C&I systems» Round trip efficiency losses outweigh GHG savings for large C&I systems despite on-peak discharge» More variable discharge for small C&I larger increase in GHG emissions» Note: these impacts do not include the contribution of storage to integrating renewables Large C&I Small C&I 31

32 RESIDENTIAL STORAGE PROJECTS

33 RESIDENTIAL PROJECTS Appear to be charging from solar and responding to rates Total kwh of Discharge (Charge) per kw Rebated Capacity, Residential Projects, 2015 H o u r Month Box shows hours that correspond with utility s higher TOU rate H o u r Total kwh of Solar Output, Residential Projects, 2015 Month All residential projects in our sample are paired with solar 33

34 WHAT S NEXT? Rates, etc.» Storage prices will continue to drop, seeing a shift towards longer duration storage (4hr vs 2hr)» If utilities continue phasing out NEM tariffs, solar + storage value proposition will increase Hawaii, Australia, Arizona, Nevada, California In CA, SGIP will now prioritize projects paired with PV» Increased demand charges -> increased storage» Increased ability for utilities to control load 34

35 HOW TO THINK ABOUT STORAGE?» Annual, monthly, and daily energy impacts are negligible (small net increase)» Impacts on the customer load shape are somewhat unpredictable in both magnitude and timing Not all peaks are shaved» We don t expect to see any mitigation of the duck curve until NEM or feed in tariffs are phased out Will lead to solar self consumption 35

36 HOW TO MODEL STORAGE?» Dispatch models (AMI data + PV data + tariff + storage info) Typically assume perfect optimization based on load, customer generation, and rates Not representative of current storage technologies Not representative of current» Sub-metering Can be costly, not always actionable 36

37 KEY TAKEAWAYS FOR LOAD FORECASTING» Energy impacts at all levels (customer/feeder/system) are negligible» Storage behavior can largely (albeit imperfectly) be predicted based on tariffs Commercial customers with high demand charges will primarily act to mitigate peak demand Residential customers on TOU rates will primarily act to shift load across periods Customers on NEM 3.0 tariffs will primarily act to maximize PV self consumption 37

38 THANK YOU

39 BACKUP

40 Discharge Capacity Factor METRICS: STORAGE UTILIZATION Non-Residential 2014 and 2015 Storage discharge capacity factor defined as: 70% kwh Discharge Hours of Data Discharge Capacity 60% *60% represents the SGIP Handbook assumption of 5,200 discharge hours per yr (5,200 / 8,760 = 60%) 60% 50% 40% 30% 20% 10% 0% Months of Data Available PBI Non-PBI 18 of 21 (86%) PBI projects had capacity factors of at least 10% (required to receive full PBI payment) 40