Today's political climate has made for fluid motion in regulations, and corporate average fuel economy targets haven't been left out.
Suppliers and automakers have already begun investing heavily into vehicles to be sold in 2022 through 2025, which will include various fuel-saving and emission-reducing technologies.
However, that unsettled political climate may have ramifications for the start-stop hybrid systems planned by those suppliers and automakers, according to IEEE Spectrum.
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A bit of backstory on the situation is in order, first.
This past January, the EPA finalized emission-reduction rules for the 2022 through 2025 model years at a quicker pace than expected by most automakers.
The decision was based on a technical assessment report that showed automakers had met the 2017 goals ahead of schedule and at a lower cost than projected.
Hybrid Kinetic’s microturbine-based extended-range electric powertrain
However, the assumptions used for the goals included a large portion of passenger car sales, while today's market favors crossovers, SUVs, and light trucks.
Following the change of administration, the EPA—led by climate-science denier Scott Pruitt—announced that the 2022-2025 limits will be revisited, to the delight of automakers.
However, many of the investments to meet those rules have already been made—totaling hundreds of millions of dollars—and industry analysts expect automakers and the government to reach an agreement on tweaks to the rules rather than wholesale elimination.
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The EPA has a number of options. It could push back the effective timeline—potentially up to five years—but stick with the Obama administration's overall targets.
It could also reduce penalties for automakers that don't meet the targets on schedule.
The challenge is that such prominent suppliers as Eaton and Ricardo have already begun testing new mild-hybrid systems, which had been projected to make up as much as 18 percent of new vehicle sales in 2025.
2018 Porsche Panamera Turbo S E-Hybrid, 2017 Geneva auto show
These suppliers have much to lose if their investments in new hybrid technology falls flat in market that favors utility vehicles, coupled with decidedly cheap gasoline prices.
If the government delays CAFE targets and other emission reduction regulations, it could spell trouble for those investments.
If there is one wild card at play, it's that today's automakers must develop cars for a truly global economy.
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China and Europe seem likely to keep incredibly strict emission and fuel-economy regulations, because their government regulation is based on science.
Reductions in U.S. goals would simply mean that the North American market would diverge even further from those in the rest of the world, including the world's largest market, China.
That could require automakers to build increasingly different vehicles to suit separate markets—hybrids in one market, non-hybrids for others—which could lower the volumes of such advanced technology and raise costs for both markets.