Researchers at the Massachusetts Institute of Technology (MIT) have developed a pioneering online tool called the Carbon Counter, which allows users to compare the lifetime emissions and total cost of ownership (TCO) of popular car and light truck models. The tool only looks at cars available in the United States, but this crosses over with many available in the Middle East.
The Carbon Counter looks at different vehicle types, including electric vehicles (EVs), plug-in hybrid electric vehicles (PHEVs), hybrids, and traditional internal combustion engine (ICE) vehicles.
The Carbon Counter presents a scatter plot where each vehicle is represented by a coloured dot, corresponding to its powertrain type. The vertical axis of the graph denotes emissions, while the horizontal axis represents the lifetime cost of the vehicle, giving users a clear visual indication of the “green for the buck” efficiency of each model. Users can customise various parameters such as fuel prices, electricity costs, state and federal incentives, and driving styles, enhancing the relevance and accuracy of the comparisons.
Comprehensive Lifecycle Analysis
Greenhouse gas emissions figures within the tool encompass the entire lifecycle of a vehicle. This includes emissions from vehicle production, battery production, supply chains, and raw materials. The cost figures take into account the vehicle’s purchase price, fuel expenses, and maintenance costs. It is noteworthy that the tool focuses on lifetime costs without including federal or state incentives.
One key finding is that plug-in vehicles generally emit fewer greenhouse gases compared to their fossil-fuel-only counterparts. Pure EVs stand out as the greenest option. Even the least emission-efficient EV (the Porsche Taycan) matches the emissions of the cleanest ICE vehicle (the Mitsubishi Mirage). EVs really are greener than conventional cars.
There are some surprises too. For example, the most efficient PHEVs produce marginally better environmental performance than larger, less efficient EVs. Additionally, clean vehicles often exhibit lower lifetime costs, largely influenced by their typically smaller sizes.
In contrast, the data suggests that not all PHEVs and hybrids are environmentally efficient, with some being no greener than average gas-powered vehicles and incurring significantly higher costs.
Notable Performers
Analysis of individual models reveals a range of high and low performers. Among the most environmentally efficient and cost-effective models:
Hyundai Ioniq Electric stands out as the lowest-emission vehicle available and one of the most affordable plug-ins by TCO.
Toyota Prius Prime emerges as the greenest PHEV and the second-cheapest in TCO. Remarkably, it achieves lower emissions than many pure EVs at a considerably lower price.
Tesla Model 3 (Standard Range Plus), with an MPGe rating of 140, is highly efficient and affordably priced, making it the second-greenest EV.
Conversely, some models fare poorly in both environmental and financial metrics:
Toyota Mirai, while delivering low lifetime emissions, incurs higher TCO compared to most BEVs, lacking the appeal and convenience of battery-electric models.
Audi and Jaguar have among the highest-emission and costliest plug-in vehicles.
Porsche Taycan is characterised by high emissions and high cost, albeit with performance appeal.
BMW X5 xDrive45e is noted as an expensive PHEV, on par with average-size ICE vehicles in terms of emissions.
Among the worst culprits for greenhouse gas emissions are the Toyota Tundra and Sequoia, both of which exhibit the second-highest emissions of any car or light truck available in the US, surpassed only by the Lamborghini Aventador Coupe.
If your car – or the one you’re interested in – may not be listed specifically yet, you can still get some indicative data at the International Energy Agency’s Lifecycle Assessment Calculator. This is more generic by type and size of car, type of fuel and so on. But it still gives a really good indication about the relative environmental benefits (or not) of choosing different types of vehicle.
