Electric cars still seem like a mystery to consumers — if not the vehicles themselves, at least the various factors that influence the choice. First comes the price, but maintenance costs, resale value, and probably the main question also come into play: Is replacing gas stations with charging stations or using a garage outlet a more economical option?
The conclusion of a doctoral research project conducted at the Faculty of Mechanical Engineering (FEM) of Unicamp, in partnership with the Instituto Superior Técnico of the University of Lisbon.The fact is that, in many cases, it is worthwhile to switch from combustion engine vehicles to electric ones. Some contexts prove more advantageous than others, especially when the owner is able to recharge at home, taking advantage of the benefits of distributed microgeneration of photovoltaic solar energy, that is, when the consumer generates their own electricity through solar panels. To evaluate the different scenarios, Nathalia Hidalgo Leite, author of the study, developed mathematical models to calculate the interference of various factors, both in the cost of vehicle ownership and in the generation of electricity. The thesis was supervised by professors Luiz Carlos Pereira da Silva, director of the Paulista Center for Energy Transition Studies (CPTEn) at Unicamp, and Hugo Gabriel Valente Morais, from the University of Lisbon, and co-supervised by Cindy Paola Guzman Lascano, from the Institute of Computer Systems Engineering (INESC-ID), in Lisbon.
How much?
The study relates two distinct but complementary analyses: the viability of photovoltaic solar systems, considering different credit compensation rules for consumers, and the attractiveness of electric vehicles compared to combustion-powered vehicles, through the calculation of the total cost of ownership (TCO). The models also took into account possible economic variations and subsidies for the sectors. The conclusion is that even with less compensation to consumers for the photovoltaic energy generated, the TCO of electric vehicles varies little, ranging from a reduction of 1,8% to an increase of 6,3% in their cost of ownership.
Until 2023, consumers who generated photovoltaic energy received 100% compensation. With Law 14.300/2022, it was established that the compensated amount would be progressively reduced, causing the financial return on investment to fall by an average of 5,77%. "What changed was the period of..." payback"The return on investment time has been extended. However, it remains a viable option," explains the engineer. According to Leite, recent changes in the electricity sector should not impact the long-term choice of electric vehicles. According to the research, other factors have a greater influence on the calculation of TCO in Brazil."Most combustion engine vehicles in Brazil today are flex-fuel, meaning they can also be fueled with ethanol. This was taken into account in the mathematical models," he explains.
Considering four vehicle categories—entry-level, compact, mid-size, and luxury—and the various compensation rules, the researcher outlined 23 scenarios comparing the Total Cost of Ownership (TCO) of electric and combustion vehicles. In 12 of these scenarios, there was a tie; in two, the cost of electric vehicles was higher; and in nine scenarios, combustion vehicles had a higher TCO. Among the different factors, the one that most impacts the TCO calculation for electric vehicles is the initial value of the vehicles, especially compact ones.
Leite highlights aspects specific to the Brazilian context that should be considered in studies of this type, demonstrating how energy recharge conditions affect costs. One of these aspects is the still limited number of charging stations in the country. ABVE counts 16,8 charging stations, a ratio of 20,9 vehicles per station. "With the growing demand from people buying electric and hybrid vehicles, the price [of energy] at charging stations tends to be higher." Another factor is cultural: according to the researcher, studies in the area show that few owners of hybrid vehicles... plug-in — which allow for refueling and recharging — have a habit of recharging them. “Most of the time, they are carrying extra weight on the batteries and consuming more fuel because of it. That's not efficient,” he comments.
Policies for the sector
Another aspect highlighted in the research, and which fosters new studies on the elements driving the energy transition, is that the intrinsic factors of electric vehicles and photovoltaic energy generation cannot be dissociated from public policies for the sector. In Leite's view, Brazil currently only has general policies for vehicle efficiency. She cites the example of the rules for exemption from the Tax on Motor Vehicle Ownership (IPVA), which do not follow a national guideline. "Several states offer some type of tax benefit, but the scenario is far from uniform across the country."
The researcher believes that the country needs to prioritize the decarbonization of its energy matrix and, based on that, develop policies that include electric vehicles and other resources and strategies, such as the adoption of electromobility in public transportation."Starting with buses and other electric modes of transport would be a good option to expand the country's progress towards the energy transition."
