Tailored emails prompt electric vehicle owners to engage with tariff switching information


The carbon intensity of the electricity used to charge an electric vehicle (EV) is dependent on when in the day charging occurs. However, persuading EV owners to adopt incentives to charge during off-peak hours is challenging. Here we show that governments could exploit the ‘window of opportunity’ created when people purchase their first EV to promote time-of-use tariffs. Email recipients (n = 7,038 EV owners) were more likely to click-through to an information webpage when the email emphasized specific reductions in home-charging costs versus general bill savings. However, the ‘window of opportunity’ for maximizing potential adoption is short; email open rates declined from over 70% immediately after purchase to 40% for recipients owning their EV for over three months. These results demonstrate the potential of prompts to change behaviours for which opt-out enrolment (where enrolment is automatic unless people explicitly opt out) would be unethical or less effective.

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Figure 1: Experimental procedure.
Figure 2: Percentage of emails opened and clicks-through to online advice page by experimental condition.
Figure 3: Percentage of emails opened by the time in months since the recipient purchased their electric vehicle.


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M.N. is funded by the EPSRC Centre for Doctoral Training in Energy Demand (LoLo), grant numbers EP/L01517X/1 and EP/H009612/1. G.M.H., D.S. and S.E. are supported by Research Councils UK (RCUK) Centre for Energy Epidemiology, grant number EP/K011839/1. We would like to thank Nicholas Brooks and Thomas Younespour at the UK Government Office for Low Emission Vehicles for the substantial contribution they made to executing the project.

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M.N. conceived, designed and implemented the research project, with substantial input on the design, analysis and interpretation of data from G.M.H. and D.S. G.M.H. provided critical revisions of the pre-analysis plan and critical revisions of the manuscript. D.S. also provided critical revisions of the manuscript. S.E. assisted with the creation of the data sharing agreement between UCL and the Office for Low Emission Vehicles and facilitated the introduction of the Energy Saving Trust into the project.

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Correspondence to Moira Nicolson.

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The authors declare no competing financial interests.

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Nicolson, M., Huebner, G., Shipworth, D. et al. Tailored emails prompt electric vehicle owners to engage with tariff switching information. Nat Energy 2, 17073 (2017). https://doi.org/10.1038/nenergy.2017.73

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