Mark P. Mills, Senior Fellow at Manhattan Institute, just released his latest report on electric vehicles, titled “Electric Vehicles for Everyone? The Impossible Dream.” In his detailed 48-page report, Mills provides compelling evidence to support his thesis that proposed government mandates on tailpipe emissions will effectively eliminate gasoline-powered vehicles and force automobile manufacturers to produce primarily all-electric vehicles (EVs). Mills’ report confirms my view that plug-in hybrids (PHEVs), with a caveat, should ultimately win the day from a practical perspective in terms of providing the best option for most motorists, as compared to EVs and mild hybrids.

Mills’ key argument — one that seems to be entirely lost on states that have instituted EV mandates — is that building out an all-EV infrastructure is entirely impractical. Only one-third of American households have a garage, which will require two-thirds of American households to use public DC “fast” chargers. The problem with these chargers, which are commonly rated at 150 kWh, is they can take anywhere from 30 minutes to an hour to charge an EV from 10% to 80% (the wide range of charging times is due to the multiple variables that determine charging speed).  The advertisements of “5% to 80% in 22.5 minutes” would only be true in a perfect world with a 350 kWh charger operating at their maximum rating.  The claim is unrealistic and misleading, since public chargers often don’t charge at their maximum kWh rating, and no current EVs can charge at a full 350 kWh.

Given the long charging times of current battery technology, Mills notes that to achieve the same convenience in terms of waiting times at a filling station, four chargers would be required for each gasoline pump. This would mean filling stations would have to grow dramatically to accommodate the additional chargers, doubling the overall cost of building the average filling station. Since 99% of filling stations are not owned by “big oil” companies, but are small mom-and-pop businesses who make very little profit on gasoline, the all-electric mandate could spell the death of most of them — especially if one considers the number of electric vehicle chargers required to produce a steady stream of customers purchasing convenience store items, which is where most of the profit resides.

Many people purchase EVs with the idea they are contributing towards reduced CO₂ emissions to “save the planet” from the perceived negative effects of climate change. While it is indeed possible that EVs will reduce CO2 emissions (some estimate reductions up to 50%), it is not necessarily the case that an EV will lead to a reduction in CO₂ emissions. While an EV emits no emissions itself during its lifetime, the “upstream” industrial process of acquiring the materials and processing them to make the battery requires enormous amounts of CO₂ emissions — in fact, up to ten times as much as an internal combustion engine (ICE) vehicle. Also, CO₂ emissions from electricity production to power the grid for EV charging can vary widely and can even be as high as that of an ICE vehicle, all depending on how the energy is produced. Given such a high variability for both the upstream and downstream numbers, it is truly a guess as to how much CO₂ emissions will decline as an increasing number of EVs take to the road.

PHEVs, on the other hand, provide a balance for motorists with virtually no downsides (except for one that I will explain shortly). First, PHEV batteries are 1/5 to 1/6 the size of EV batteries, so the environmental degradation of building a PHEV battery is a small fraction relative to an EV. Second, if regularly charged at home or at work, daily commutes can be done while rarely running the gasoline engine, saving on money and CO₂ emissions. When the battery is depleted, the gasoline engine kicks in, and the vehicle will operate the same as a hybrid. Thus, PHEVs have the advantages of an EV for short commutes while also having a gas engine for longer trips without worrying about hunting for a charger, being limited on range as with virtually all EVs, or being disappointed because a charger is either broken or doesn’t deliver at or near its kWh rating (which happens often here in Southern California).

An advantageous feature of PHEVs is that the gasoline engine can charge the battery at higher speeds where it is at its most efficient, allowing the electric motor to power the vehicle at idle or slower speeds when the gasoline engine is at its least efficient.  When the gasoline engine is charging the battery, fuel economy will be significantly lower as it is working harder to move the car forward while also charging the battery. Nonetheless, a PHEV not regularly charged will still deliver significantly better miles per gallon than either an all-gasoline or hybrid vehicle and when regularly charged, can rival an EV in overall efficiency since it combines the fuel economy of the electric motor and gasoline engine.

Admittedly, a major current flaw with PHEVs is they are not designed to accept fast chargers, forcing motorists to use slower, 240 volt “Level 2” chargers. With a typical 18 kWh battery and an onboard charger that will accept 7.2 kW, it would take almost two and a half hours to fully charge the battery from 0% to 100%. If the car accepted fast charging, a standard 150 kWh charger operating at or near its rating could charge the PHEV battery from 0% to 100% in about 10 minutes. This would make PHEVs more compelling, especially on longer trips, since the typical stop at a gas station to fill a tank is around 10 minutes.

If PHEVs were the preponderant vehicles, there would be no rush to build out an all-EV infrastructure, giving filling stations time to adjust and “right size” the number of fast chargers based on market demand rather than government mandates. EVs certainly have a role to play for those who can regularly charge at home and make few long trips (Tesla owners report having a great experience in this regard). Hybrids also have a role to play for those who don’t have a convenient method to charge either an EV or PHEV. Overall, however, I believe motorists would most benefit from the innovative technology of PHEVs, which can be produced by all major automobile manufacturers. Auto makers need to step up and address the one issue that makes these vehicles less practical — their inability to accept fast chargers.  When they do, PHEVs will offer the best and brightest future for automobiles.

Cross-posted at Discovery Institute.