The Effects of Plug-in Electric Vehicles on a Sample Grid Team Members: Jeff Eggebraaten Brendin Johnson Anne Mousseau Justin Schlee 1

Overview 1) Defining the problem 2) Market Research 3) Load Analysis 4) Time of Day 5) Future Work 2

Problem Statement The demand for plug-in electric vehicles is increasing rapidly, which will pose new challenges for power utilities in terms of understanding how this additional load will effect their distribution grids. Idaho Power asked EVI to perform this analysis. 3

Car Types Plug-in Electric Vehicles Run only on electricity Do not have another fuel source Plug-in Hybrid Electric Vehicles (PHEV) Run on electricity and fuel Gas engine can drive the wheels or act as a generator 4

Market Research Why is market research needed? - To predict the future number of PHEV’s on the road. 5

Source: EPRI Share of New Vehicle Sales Year Projected Plug-in Electric Vehicle Market Share 6

Market Research Gathered Information National Numbers National Yearly Sales (Autodata) Projected PHEV new car sales (E.P.R.I.) Number of cars on the road per year (D.O.T.) Regional Numbers Number of cars registered in Idaho (Idaho D.M.V) Number of cars registered in Ada county (Idaho D.M.V) Results Projected number of PHEV’s in Idaho (2010–2040) Projected number of PHEV’s in Ada county (2010–2040) 7

Projected Number of PHEV’s in Boise 8

Conductive Charger Levels Level 1 Convenience Plug into common wall outlet 1-Phase 120 V AC, 15 A* AC 1.44 kW (max) Level 2 Private/Public Requires EV Supply equipment installation 1 Phase V AC, 30-60A AC 14.4 kW (max) Level 3 Opportunity Requires commercial equipment installation 3 Phase V AC, 400 A AC 240 kW (max)** * Receptacle rating (maximum continuous current of 12 A). ** Maximum allowed by standards Source: C.C Chan, K.T. Chau 9

10 Battery Size and Charge Time

Line Voltages before PHEV loading Year

Line Voltages with PHEV loading Year

Number of Distribution Grid Issues with PHEV loading Year

PHEV Loading Mitigation Added Voltage Regulators Re-conductored Overloaded Lines Added Capacitors Approximated Cost of $132,000 14

Line Voltages with PHEV loading and Mitigation Year 2040 Capacitor Added Re conductor 2 Voltage Regulators 15

Time of Day Charging Customer comes home and plugs in the car (~5 pm) Normal utility peak (~5 pm) To reduce this load, shift the charge time (~10 pm) 16

Time of Day Analysis 17

Variable Power Rates Pros of PSE’s Variable Rate Plan: About 5% of total power usage was shifted to off-peak hours Overall electricity usage was reduced by 6% An overall positive reaction from the customers for the incentive to use energy more efficiently 18 Source: Puget Sound Energy

Variable Power Rates Cons of PSE’s Variable Rate Plan: To break even customers would have needed to use more than half their electricity during the lowest rate hours. This was an inconvenience for some families who felt that the time-of-day plan was incompatible with their lifestyle. 19 Source: Puget Sound Energy

Power Sellback – V2G Electric vehicles can be used to provide power during peak usage times Benefits Peak Shaving Load Regulation Challenges Harmonics Protection Tripping Safety 20

Future Work Power Quality Effects of Higher Charging Levels Transmission, Generation, and Protection 21

22 Conclusions By 2040 PHEV’s charging will increase load by 18% Additional load results in voltage drop Equipment will need to be upgraded to accommodate load Shifting charge time results in a 7.73% peak load reduction Time of day plan can incentivize a shift in charging time

Thanks: Idaho Power Marc Patterson, Mel Trammel, Mary Graesch University of Idaho Dr. Herbert Hess, Dr. Greg Donohoe, Dr. Joseph Law, John Jacksha 23

Market Research Calculations 24

Additional Load Due to PHEVs 25