Exploring how solar-powered electric vehicles, enhanced by lifecycle efficiency and renewable energy adoption, could significantly reduce global car pollution and pave the way for sustainable personal mobility by 2030.
23 Dec 2024 | 5012 Views | By Nilesh Bajaj, Vayve Mobility
In the ongoing quest for sustainable personal mobility, one of the most important metrics for evaluating vehicle performance is well-to-wheel efficiency. This comprehensive measure examines the energy used and emissions generated across the entire lifecycle of a vehicle —from manufacturing to fuel production to its final usage of moving people ...
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In the ongoing quest for sustainable personal mobility, one of the most important metrics for evaluating vehicle performance is well-to-wheel efficiency. This comprehensive measure examines the energy used and emissions generated across the entire lifecycle of a vehicle —from manufacturing to fuel production to its final usage of moving people on the road. By comparing small electric cars (EVs) to small petrol cars, we uncover the significant advantages of EVs, especially when it comes to reducing emissions across various stages of their lifecycle.
1. Materials and Manufacturing
Petrol Cars
Small petrol cars rely heavily on raw materials like steel, aluminum, glass, copper and plastics derived from fossil fuels. These materials are energy-intensive to produce, and their manufacturing processes emit significant quantities of greenhouse gases (GHGs).
A conventional internal combustion engine (ICE) also involves numerous complex components, each contributing to emissions during production. Carbon emissions through materials is estimated to be 3.3 kg CO2e per kg of car weight. Additional emissions from modern car manufacturing are projected as 0.7 kg of CO2e per kg of car weight. For a small petrol hatchback weighing 800 kg, the net emissions until factory gate rollout would be 3.2 tons CO2e.
Electric Cars
While EVs share many of the same material and manufacturing with petrol cars, the emissions can be reduced by innovation in smaller vehicle form factor with lower footprint. There is an additional impact from battery production - the extraction of lithium for batteries is energy-intensive. Lithium-iron-phosphate (LFP) cells have the lowest emissions of 0.07 tons per kWh from raw materials to cell factory delivery, as compared to other chemistries.
Comparison
Studies show that the production of an EV generates 30-50% more emissions than a petrol car depending upon the battery pack size. However, this upfront "carbon debt" is quickly offset during the EV's operational phase due to its superior efficiency and zero tailpipe emissions.
2. Fuel Supply Chain
Petrol Cars
The fuel supply chain for petrol cars involves exploration, drilling, transportation, refining of crude oil and distribution of petrol to pumps. Each of these stages consumes energy and emits GHGs. For example, just making a litre of petrol available at the fuel pump alone emits around 0.7 kg of CO₂ emissions. This is excluding tailpipe emissions from its subsequent burning in the engine.
Electric Cars
The energy supply for EVs depends on the electricity grid mix. In India, where dependency on coal-based power plants is higher, projected emissions for generating 1 kWh of electricity is 0.7 kg. As grids move to high share of renewable energy, EVs benefit from cleaner power sources, significantly reducing energy use emissions. Further, the centralized production of electricity in power plants is a lot more efficient and less polluting per unit of energy than individual petrol engines.
Comparison
The fuel supply chain emissions per km for petrol cars and electric cars is currently similar as the Indian grid is still dependent on non-renewable sources. But EVs can leverage the decarbonization of electricity grids. As renewable energy adoption increases, grid emissions for EV charging are set to decrease dramatically – even more so as customers take advantage of self-managed solar power generation.
3. Operational Efficiency
Petrol Cars
Internal combustion engines are inherently inefficient, converting only 20-30% of the energy in gasoline into motion. The rest is lost as heat. Additionally, petrol cars emit CO₂, carbon monoxide, nitrogen oxides, and particulate matter directly from the tailpipe. Burning 1 litre of petrol creates 2.4 kg of Co2e, right near the road where people live and travel. Over a lifetime 8-10 yrs, tailpipe emissions are twice as much as emissions from material & manufacturing of the petrol car itself.
Electric Cars
Electric motors are far more efficient, with entire well-to-wheel energy conversion rates often exceeding 80%. They produce no tailpipe emissions, making them ideal for urban environments where air quality is an increasingly critical concern.
Comparison
The stark difference in operational efficiency between EVs and petrol cars underscores the former's environmental advantage, especially in reducing urban air pollution.
4. Total Lifecycle Emissions
Petrol Cars
Over a vehicle's lifetime (approximately 80,000 kilometers), a small petrol car can emit upwards of 15-20 tons of CO₂, considering both operational and upstream emissions.
Electric Cars
For EVs, lifecycle emissions vary depending on the energy grid mix, battery pack size and vehicle’s weight itself. City vehicles specially built for medium-speed can bring total lifecycle emissions range between 5-6 tons of CO2e, even in coal-dependent grids. Comparison
On a lifecycle basis, EVs consistently outperform petrol cars in emissions reduction, often halving the total carbon footprint. EVs can do even better vs. traditional petrol cars with smart consumers going for smaller, lighter vehicles for city use.
5. Battery Repurpose and Recycling
One key advantage of EVs lies in the multiple lifes of their batteries. A car battery which has reduced ability over time can have a second life in an industrial vehicle with lower loads. Even after this second life, the battery can be repurposed to serve a third life as a fixed energy storage system like a home or business UPS. Emerging technologies allow for the recovery of up to 90% of key materials like lithium, cobalt, and nickel, reducing the need for virgin material extraction.
Conclusion
Electric cars demonstrate a clear advantage over small petrol cars in well-to-wheel efficiency, particularly when considering emissions across materials, manufacturing, fuel supply, and tailpipe phases. While EVs have a higher initial environmental cost due to battery production, their operational efficiency and reliance on cleaner electricity grids allow them to quickly break even and surpass petrol cars in environmental performance.
As grid decarbonisation progresses and battery technologies improve, the gap in well-to-wheel efficiency between EVs and petrol cars will only widen, solidifying EVs as the more sustainable choice for personal mobility, and for cleaner air for all.
Disclaimer: Nilesh Bajaj is a co-founder and CEO of Vayve Mobility. The views expressed are purely those of the author.