In a post published on Medium, Gill Pratt, Toyota Motor Corporation’s Chief Scientist and the CEO of Toyota Research Institute, explains why he is not a proponent of ditching ICE and switching to only BEVs as soon as possible. He argues that a diversity of electrified drivetrain types are better means of addressing climate change than “a monoculture of only BEVs” for two main reasons:
Battery cell production is expensive, uses natural resources and produces significant greenhouse gases. Maximizing the benefit of every battery cell produced requires using them smartly.
This means putting them into a greater number of “right sized” electrified vehicles, including HEVs and PHEVs, instead of placing them all into a fewer number of long-range BEVs, like my model X. This is particularly important because presently it is difficult to recycle the kinds of batteries used in BEVs. If we are to achieve carbon neutrality, we must pay attention to all parts of the “3R” process — Reduce, Reuse, and Recycle.
For example, we hardly ever put gas into our RAV4 Prime PHEV, which has a battery ⅙ as large as our Model X BEV. For the same investment in batteries as our single Model X, five other RAV4 Prime customers could reduce their carbon footprint too.
Second, different people have different needs. In some parts of the world, people have access to highly renewable electric power and BEV rapid charging stations. In many other parts of the world, rapid chargers are rare, or electricity is generated with high carbon emissions resulting in BEVs putting more net carbon into the air over their lifetime than PHEVs and in some cases even HEVs.
So, even if the best choice for the average person someday becomes a BEV, it will not be the best way for every person to contribute to reducing carbon emissions, or for the most carbon emissions to be eliminated.
Carbon is the enemy, not ICEs, Pratt writes, adding that in many parts of the world for some time to come, PHEVs and even HEVs will generate comparable or less lifetime carbon than BEVs. Toyota has open-sourced a modeling and simulation tool to support this contention.
(This is counter—specifically in relationship to PHEVs— to the conclusion in the recent ICCT lifecycle analysis (earlier post), which found that compared to average BEVs in the United States, Europe, and China, the life-cycle GHG emissions for PHEVs are 43%–64%, 123%–138%, and 39%–58% higher for cars registered in 2021 and 53%–100%, 171%–197%, and 94%–166% higher for cars expected to be registered in 2030.)
The atmosphere accumulates carbon over long periods of time, so the carbon we emit now will be with us for a century or more. Our responsibility is clear: We must eliminate carbon emissions as soon as possible. As a scientist, I know that, to paraphrase Einstein, the solution of how to eliminate carbon as soon as possible should be as simple as possible, but no simpler.
As a result, I believe, as does Toyota, that it would be a tremendous mistake for governments around the world to prescribe narrow solutions like insisting that all vehicles be BEVs. Instead, the better solution is to allow manufacturers to innovate across a diversity of drivetrains and drivers to choose the low-carbon drivetrain that suits their circumstances best.