EV Emissions: The Calculus Behind a Sustainable Future

The Uncertain Path to Lower Emissions with Electric Vehicles

A widespread belief among investors and politicians suggests that transitioning to an all-electric vehicle (EV) future will substantially decrease global carbon dioxide emissions. However, the certainty of this outcome is questionable.

Increasing research indicates that a large-scale shift from traditional vehicles to EVs may have a limited effect on overall global emissions. It is even conceivable that such a transition could increase emissions levels.

The Significance of Embodied Emissions

The primary concern isn't the emissions generated during electricity production. Instead, it centers on the complexities and unknowns surrounding the production phase of EVs, specifically the “embodied” emissions stemming from the intricate supply chains required to source and process the materials for battery fabrication.

All manufactured goods possess embodied emissions, which are often “hidden” within upstream production processes. This applies to items ranging from food to housing and electronics, including batteries. France’s High Climate Council highlighted this issue in a study released last year.

The analysis revealed that France’s reported decline in carbon dioxide emissions was misleading. Actual emissions had risen and were approximately 70% higher than initially reported when accounting for the embodied emissions associated with the country’s imports.

Quantifying the Complexities

Accurately quantifying embodied emissions presents significant challenges, particularly in the context of EVs, where complexities and uncertainties are abundant. While EVs produce zero emissions during operation, roughly 80% of their total lifetime emissions originate from the energy used in battery fabrication and electricity generation to power the vehicle.

The remaining 20% is attributed to the manufacturing of the vehicle’s non-battery components. This contrasts sharply with conventional cars, where approximately 80% of lifecycle emissions come from burning fuel, and the remaining 20% from manufacturing the car and producing gasoline.

The fuel cycle for conventional vehicles is well-defined, closely monitored, and largely free of assumptions. This is not the case for EVs.

Variability in Battery Production Emissions

A review of 50 academic studies revealed that estimates for embodied emissions in a single EV battery ranged from around eight tons to as much as 20 tons of CO2. A more recent technical analysis narrowed the range to four to 14 tons.

The higher end of these estimates approaches the total CO2 produced over the lifespan of an efficient conventional vehicle, and this is before the EV is delivered to a customer and driven.

These uncertainties arise from inherent and potentially unresolvable variations in the energy sources and processes used throughout the battery production cycle, influenced by geographical location and proprietary manufacturing techniques. Calculations of embodied emissions are therefore inherently estimates based on numerous assumptions.

Currently, it is impossible to accurately measure or predict an EV’s true carbon dioxide “mileage.”

The Need for Scrutiny

With increasing investment flowing into government programs and climate-tech funds – 2021 is projected to surpass 2020’s record climate-tech investments, with firms like BlackRock, General Atlantic, and TPG each launching new $4 billion to $5 billion clean tech funds – a thorough examination of EV embodied emissions, and other proposed climate solutions, is urgently needed.

This scrutiny may not yield the anticipated results.

Data Mining in the Automotive Sector

A primary design objective for all vehicles centers on minimizing the weight allocated to the fuel system, thereby maximizing space for passengers and cargo. While lithium batteries represent a significant advancement – even earning recognition with a Nobel Prize – they currently lag behind petroleum in terms of energy density when considering the metric for powering mobile machinery.

The theoretical energy density of lithium-based chemicals, excluding the complete battery cell, can reach approximately 700 watt-hours per kilogram (Wh/kg). This is roughly five times greater than lead-acid battery technology, yet it remains a small fraction of the 12,000 Wh/kg offered by petroleum-based fuels.

To match the driving range provided by 60 pounds of gasoline, an electric vehicle (EV) battery typically requires a weight of around 1,000 pounds. The weight difference between electric and gasoline engines – usually around 200 pounds lighter for the electric motor – does little to offset this substantial disparity.

Manufacturers attempt to mitigate the battery’s weight impact by utilizing lighter materials like aluminum or carbon fiber in the EV’s construction, instead of steel. However, these alternatives are, respectively, 300% and 600% more energy-intensive to produce per pound than steel. Incorporating a half-ton of aluminum, a common practice in many EVs, contributes an additional six tons of CO2 to the embodied emissions – a factor often overlooked in analyses.

However, the most significant emissions challenges arise from the elements required to manufacture the battery itself.

Numerous elemental combinations are possible in lithium battery chemistries, with choices dictated by the need to balance performance characteristics such as safety, energy density, charging speed, and lifespan. The embodied energy associated with the core battery chemicals can fluctuate by as much as 600% depending on the chosen formulation.

Let's examine the key components in the prevalent nickel-cobalt battery chemistry. A standard 1,000-pound EV battery typically contains approximately 30 pounds of lithium, 60 pounds of cobalt, 130 pounds of nickel, 190 pounds of graphite, and 90 pounds of copper. (The remaining weight consists of steel, aluminum, and plastic.)

The uncertainties surrounding embodied energy begin with the ore grade – the concentration of the desired mineral within the rock. Ore grades can vary significantly, from a few percent down to as little as 0.1%, depending on the mineral, the mining location, and the passage of time. Based on current averages, the amount of ore that must be mined – utilizing energy-intensive heavy machinery – to produce a single EV battery is approximately: 10 tons of lithium brines for the 30 pounds of lithium; 30 tons of ore for the 60 pounds of cobalt; five tons for the 130 pounds of nickel; six tons for the 90 pounds of copper; and roughly one ton of ore for the 190 pounds of graphite.

Furthermore, the “overburden” – the amount of earth removed to access the mineral-bearing ore – must be considered. This quantity also varies considerably, depending on the ore type and geological conditions, typically ranging from three to seven tons of earth excavated for each ton of ore accessed. Considering all these factors, the fabrication of a single half-ton EV battery can necessitate the excavation and relocation of around 250 tons of earth. Subsequently, approximately 50 tons of ore are transported and processed to extract the targeted minerals.

The embodied energy is also influenced by the location of the mine, a factor that is currently quantifiable but subject to speculation regarding the future. Remote mining sites often require increased trucking and reliance on off-grid electricity, frequently generated by diesel generators. Presently, the mineral sector accounts for nearly 40% of global industrial energy consumption. Moreover, over half of the world’s batteries – or the essential battery chemicals – are produced in Asia, where coal-dominated electric grids are prevalent. Despite aspirations for increased production in Europe and North America, forecasts predict Asia will maintain its dominance in this supply chain for the foreseeable future.

The Significant Variability in Power Grids and Battery Production

Many evaluations of electric vehicle (EV) emissions acknowledge the inherent carbon debt associated with battery production. However, this factor is frequently assigned a singular, simplified value when determining the variations in emissions resulting from EV use across different electrical grids.

A recent study conducted by the International Council on Clean Transportation (ICCT) serves as a valuable illustration. Utilizing a standardized carbon debt figure for batteries, the ICCT investigated how an EV’s lifecycle carbon footprint fluctuates based on its operational location within Europe. The findings indicated that, in comparison to a fuel-efficient conventional vehicle, an EV could yield lifecycle emissions reductions ranging from as high as 60% in Norway or France, to approximately 25% in the U.K., and minimal reductions when operated in Germany. (Germany’s grid exhibits comparable average carbon emissions per kilowatt-hour to those of the United States.)

The analysis employed average grid emission data, which may not accurately reflect the emissions occurring during actual charging times. The precise moment of charging, rather than the average, dictates the true source of electricity utilized for vehicle operation. Gasoline consumption, conversely, lacks such temporal and locational ambiguities; its emissions profile remains consistent regardless of time or place. While the timing factor introduces limited variability in regions like Norway and France, where electricity generation is predominantly hydro and nuclear respectively, it can fluctuate dramatically in other areas, potentially ranging from 100% solar to 100% coal depending on the time of day, month, and geographic location.

Another ICCT analysis, also relying on annualized grid averages, calculated lifecycle emission reductions of roughly 25% for EVs in India, extending to 70% in Europe when compared to average cars. However, similar to the intra-European assessment, a single, fixed battery fabrication carbon debt was presumed, and at a relatively conservative level.

Considering the spectrum of potential embodied battery emissions, rather than a single average value, is prudent, as the IEA and others report that the majority of mineral extraction processes currently operate at the higher end of emissions “intensity.” Adjusting the ICCT results to reflect this reality reduces the calculated lifecycle EV emissions savings to around 40% (versus 60%) in Norway, to negligible reductions in the U.K. or the Netherlands, and even a potential 20% increase for EVs driven in Germany.

These uncertainties do not end here. The ICCT, mirroring many comparable analyses, based its calculations on batteries 30% to 60% smaller than those needed to achieve the 300-mile range essential for widespread adoption as replacements for traditional vehicles. Larger batteries, increasingly common in premium EVs, proportionally increase the carbon debt, potentially negating or significantly diminishing lifecycle emissions benefits in numerous locations.

Furthermore, forecasts of future emissions savings often presuppose that the battery supply chain will be situated within the country of EV operation. A frequently referenced analysis, for instance, assumed U.S. aluminum demand for EVs would be met by domestic smelters powered primarily by hydroelectric dams. While theoretically feasible, this scenario does not align with current realities. The United States currently accounts for only 6% of global aluminum production. Assuming instead that industrial processes are located in Asia results in lifecycle emissions calculations 150% higher.

A fundamental challenge for EV carbon accounting is the absence of reporting mechanisms or standards comparable to the transparency observed in the petroleum industry – from extraction to refining and consumption. Researchers recognize these data limitations, although these concerns are not always prominently featured in summaries or media reports. Technical publications often include caveats, such as the statement that “a greater understanding of the energy required to manufacture Li-ion battery cells is crucial for accurately assessing the environmental implications of increasing Li-ion battery usage.” Another recent study notes: “Unfortunately, industry data for the remaining battery materials are scarce or nonexistent, compelling LCA [lifecycle analysis] researchers to rely on engineering calculations or approximations to address data gaps.”

These “data gaps” widen considerably when considering the expansion of the global mineral supply chain required to support the production of tens of millions of additional EVs.

The Increasing Demand for Energy Transition Minerals

A significant factor often overlooked is the anticipated increase in energy costs linked to sourcing the necessary quantities of “energy transition minerals” (ETMs), as defined by the International Energy Agency (IEA).

The IEA recently published a comprehensive report detailing the difficulties in supplying ETMs for the production of batteries, as well as components for solar and wind energy systems. This report corroborates previous observations made by other analysts. Electric vehicles (EVs), in total, necessitate approximately 500% more critical minerals per vehicle when contrasted with conventional automobiles.

Currently, the relatively small proportion of EVs – less than 1% of the global vehicle fleet – has prevented a substantial impact on global supply chains regarding, for example, copper usage. However, scaling up EV production, alongside the expansion of grid batteries and renewable energy infrastructure, is projected to elevate the “clean energy” sector’s copper consumption to over half of the global total, rising from the current 20%.

To illustrate the magnitude of demand that EV adoption will place on mining operations, consider that a global fleet of 500 million electric cars – still less than half of all vehicles – would require mineral resources equivalent to building batteries for approximately 3 trillion smartphones. This equates to over 2,000 years of current mining and production levels for smartphones.

Furthermore, it’s important to note that such a fleet would only eliminate around 15% of global oil consumption. Beyond the environmental, economic, and geopolitical consequences of such extensive mining expansion, the World Bank highlights “a new set of challenges for the sustainable development of minerals and resources.”

This increase in mining activity directly impacts predictions regarding the future carbon intensity of mineral production, as raw material acquisition already accounts for nearly half of the life-cycle carbon dioxide emissions associated with EVs. The IEA report also acknowledges that ETMs possess a “high emissions intensity,” and that energy consumption per unit of mined material has been increasing due to declining ore grades.

The situation with copper serves as a clear example of this challenge. Between 1930 and 1970, advancements in post-mining chemical processes resulted in a 30% reduction in energy usage per ton of copper produced, despite a gradual decline in ore grades.

However, these improvements were largely one-time gains, approaching the limits of what is physically possible. Consequently, over the subsequent four decades, as ore grades continued to fall, energy consumption per ton of copper increased, ultimately returning to the levels observed in 1930. A similar pattern is anticipated for other minerals as ore grades continue their downward trend.

Despite this, the IEA, along with other organizations, utilizes current, and potentially underestimated, average supply-chain emissions intensities to project that EVs will reduce emissions in the future. However, the IEA’s own data indicate rising embodied emissions for ETMs.

Adding to this, the construction of more solar and wind facilities – which the IEA notes require 500% to 700% more minerals than building a natural gas power plant – will further strain the mining supply chain, likely leading to substantial price increases. Resource experts at Wood Mackenzie predict that if EVs reach a 10% market share, material demands will become unsustainable.

They state that achieving EV targets and internal combustion engine (ICE) bans will be impossible without unprecedented advancements in battery technology development, testing, commercialization, manufacturing, and supply chain integration. There is currently no indication of the capacity to accelerate these processes at the pace required by policy goals.

For instance, nearly three decades elapsed between the discovery of lithium battery chemistry and the introduction of the first Tesla sedan.

Addressing Carbon Footprints Within Battery Supply Chains

Several strategies exist to lessen the impact of factors contributing to rising emissions within electric vehicle (EV) supply chains. These include advancements in battery chemistry, optimized chemical processes, and the electrification of mining equipment alongside enhanced recycling initiatives. These solutions are frequently presented as unavoidable or essential steps forward.

However, achieving a substantial impact within the timelines required for widespread EV adoption remains a significant challenge. Despite frequent reports of “breakthroughs” in the news, no currently viable alternative battery chemistries fundamentally alter the quantity of physical materials needed per mile traveled by an electric vehicle.

Often, alterations to chemical formulations simply redistribute the environmental burden. For instance, reducing cobalt usage typically involves increasing nickel content. Furthermore, chemistries that aim to eliminate high-energy elements like carbon or nickel, substituting them with lower-intensity alternatives such as iron – as seen in lithium-iron-phosphate batteries – generally result in reduced energy density.

This lower density necessitates larger and heavier batteries to achieve comparable vehicle range. While the eventual discovery of fundamentally superior battery chemistries is plausible, the process of validating and safely scaling up industrial chemical systems requires considerable time. The batteries powering vehicles today, and in the foreseeable future, will rely on currently available technologies, not those still in development.

Improvements in the efficiency of chemical processes used in mineral refining and conversion are also anticipated. Such advancements are natural, driven by ongoing engineering efforts, and increasingly facilitated by digital technologies. However, significant, disruptive changes aren't expected in the established field of physical chemistry, where processes already operate close to theoretical limits.

In essence, lithium battery technology has moved beyond the phase of rapid process and cost improvements, now experiencing only incremental gains. Electrification of mining trucks and equipment is being actively pursued by manufacturers like Caterpillar, Deere, and Case, with some production models already available.

While promising designs are emerging for specific applications, batteries currently lack the consistent performance required for 24/7 operation of heavy mining equipment. Moreover, the replacement cycle for mining and industrial equipment extends over decades, meaning oil-powered machinery will remain prevalent for a considerable period.

Finally, recycling is often cited as a means to offset increasing demand. Even with complete battery recycling, the capacity would fall far short of meeting the substantial increase in demand projected from the planned expansion of the EV market. Technical and economic hurdles remain in effectively recycling critical minerals from complex devices like batteries.

Although automated recycling capabilities are envisioned, they do not currently exist. The diversity of current and future battery designs further complicates the development of such capabilities within the timeframes considered by policymakers and EV advocates.

The Potential for Legal Issues Surrounding EV Emission Credits

A significant challenge exists due to the numerous assumptions, estimations, and unclear aspects involved in calculating EV emission reductions. This creates a vulnerability where claims of reduced emissions could be manipulated, or even become fraudulent. Obtaining the necessary data for proper regulation is likely to be problematic.

Technical complexities, diverse geographical influences, and the confidential nature of many related processes contribute to this difficulty. Despite these hurdles, the Securities and Exchange Commission is reportedly contemplating the implementation of such disclosure requirements.

The inherent uncertainties within the EV sector could trigger substantial legal complications if regulators in both Europe and the United States formally establish legally enforceable “green disclosures” or “responsible” ESG metrics related to carbon dioxide emissions.

A More Immediate Solution for Reducing Automotive Oil Consumption

For policymakers focused on decreasing reliance on automotive oil, a readily available and more reliable solution already exists. This alternative bypasses the need to wait for breakthroughs in battery technology and mining practices.

Combustion engines with commercially feasible designs are capable of reducing fuel consumption by up to 50%. Incentivizing consumers to adopt these more efficient engines, even by capturing half of this potential, would prove more cost-effective and quicker to implement.

Furthermore, the results would be transparently verifiable, offering a clear advantage over the extensive undertaking of adding 300 million EVs to global roadways.

Key Considerations

• The complexity of accurately measuring EV emission reductions.
• The potential for manipulation and fraud in emissions reporting.
• The availability of more immediate and verifiable solutions through improved combustion engine technology.
• The cost-effectiveness of incentivizing efficient engine purchases.