Graduation Year


Document Type




Degree Name

MS in Civil Engineering (M.S.C.E.)

Degree Granting Department

Civil and Environmental Engineering

Major Professor

Michael Maness, Ph.D.

Committee Member

Fred Mannering, Ph.D.

Committee Member

Nikhil Menon, Ph.D.


Zero-Price Effect, Range, Charge Time, Detour Time


Although there is economic and marketing evidence of consumers assigning additional benefits to free products and bundles, there is limited research into the behavioral consequences of offering public electric vehicle charging for free. Previous exploratory research by Maness and Lin analyzed possible economic and environmental benefits from offering free public charging infrastructure and policy. Their work found that providing free public charging infrastructure could increase plug-in electric vehicle sales and cause decreased reliance on fossil fuels in the personal transportation sector. However, their study assumed the increased value which consumers would place on free charge events. This project proposes to establish an early estimate of the value of free charging in the United States. To solve the problems such as lack of a control treatment and lack of variability in charging prices, this project proposes to study consumers' responses to a free charging program through a stated preference approach. Under this approach, valuation behaviors were explored through charger choice and vehicle choice experiment. In charger choice scenarios, the respondents were presented with charging location choice where three charging stations were presented with one charger being free and the others having a cost. In vehicle choice scenarios, the respondents were presented with vehicle choice where two EVs were presented with zero, one, two, or three years free charging along with a gasoline vehicle. Various discrete choice models were used for estimation. Determining the zero-price effect entailed adding a dummy variable to the model for when fueling cost was zero. The data used for the estimation was weighted to fit the US population. It should be remarked that the computations are based on Bayesian estimation from Greene (2004). The ZPE values were evaluated concerning individual-level parameters for the parameters that were discovered to be random (varying across individual). The results suggested that the weighted mean zero-price effect for the charger choice is valued at -$1.44 (Mixed logit model) and at -$1.19 (Latent class model) and the mean national ZPE for the entire US population was priced at -$0.96 per charging event. Additionally, the mean value of time (VOT) in regards to charging was valued at $7.66/hr (Mixed logit) and $8.15/hr (Latent class). Similarly, the value of time associated with the detour is found to be valued at $13.46/hr (Mixed Logit) and $11.71/hr (Latent class). The weighted mean zero-price effect for two years of free charging was valued at $3952 for the electric vehicle binary choice and $4200 for the electric and conventional vehicle choice. For three years of free charging, it was valued at around $4709 and $6319. The value of driving range was estimated at $67 and $143. The WTP for the driving range confirmed with the value obtained from the previous research by Dimitropoulos et al. (2013) and Greene et al. (2017). Although a limitation of stated preference studies is in determining the correct scale for the coefficient estimates, the value of time estimated is close to the USDOT personal travel VOT of 50% of hourly median household income.