Introduction

  • BEV (Battery Electric Vehicle) reduces \(CO_2\) and prevents air pollution.
  • However, managing BEV loads has become a problem.
  • Introducing smart charging: SMC and V2G.

SMC - Supplier Managed Charging

  • SMC smooths out overnight EV charging demand.
  • Electricity demand is controlled below capacity threshold.

V2G - Vehicle-to-Grid

Research Questions

  1. Sensitivity: How do changes in smart charging program features influence BEV owners’ willingness to opt in?

  2. Market Share: Under what conditions will BEV owners be more willing to opt in to smart charging programs?

Conjoint survey to collect BEV owners’ willingness.

Mixed logit model to evaluate utilities for simulations.

Survey Design with formr

  1. Conjoint Questions:
    1. Monetary Incentives: one-time + recurring payment.
    2. Charging Limitations: remaining battery.
    3. Flexibility: monthly override (SMC) or occurrence (V2G).
  2. Demographic Questions:
    1. Heterogeneity: How different the BEV owners are based on their demographic information.
    2. Aspects: BEV ownership, charging habits, commute method, age, income, house type, family size, etc.

SMC Programs

Attributes

No. Attributes Range
1 Enrollment Cash $50 to $300
2 Monthly Cash $2 to $20
3 Monthly Override 0 to 5
4 Min Battery 20% to 40%
5 Guaranteed Battery 60% to 80%

Sample Program

Attributes Values
Enrollment Cash $300
Monthly Cash $20
Monthly Override 5

V2G Programs

Attributes

No. Attributes Range
1 Enrollment Cash $50 to $300
2 Occurrence Cash $2 to $20
3 Monthly Occurrence 1 to 4
4 Lower Bound 20% to 40%
5 Guaranteed Battery 60% to 80%

Sample Program

Attributes Values
Enrollment Cash $300
Occurrence Cash $20
Monthly Occurrence 1

Sample SMC Question

Sample V2G Question

Survey Results

  • Over 800 valid results from social media.
  • Conjoint: all attributes are contributive to enrollment, including “No Choice”.
  • Demographic: rich elders with 2 or more vehicles.

Mixed Logit Models Using logitr R Package

\[ \begin{align*} u_j = v_j + \epsilon_j = \beta' x + \epsilon_j \qquad P_j = \frac{e^{v_j}}{\sum_{k=1}^{J} e^{v_k}} \end{align*} \]

SMC Estimates

V2G Estimates

Sensitivity Analysis

Steeper slop indicates higher sensitivity.

Tornado Plots

  1. Monetary incentives are important.
  2. Recurring incentive is more important than one-time.
  3. For SMC, range anxiety is vital, since it happens regularly.
  4. For V2G, usability is compromised.
  5. Diminishing returns exist.

Market Simulation for SMC

Market Simulation for V2G

Future Work

Data Collection

  • Other than social media, use survey panels to collect more responses.
  • Increase data size from 800 to 2000.

Modeling

  • Subgroup analysis considering heterogeneity.
  • More modeling techniques such as Apollo Choice Modeling.

Simulation

  • Apply customer preferences to grid simulation.
  • Estimate benefit-cost trade-offs for utilities.

Pingfan Hu - IEEE VPPC 2024