Current EV technology works well, but it isn’t what American drivers need.
Hybrids are popular in the automotive market and are widely seen as a transitional step towards a fully electric future. But getting there will require infrastructure that may take years to build. As they are currently built, hybrids are primarily internal combustion engine vehicles with small additional battery drivetrain. But is this the best form to bridge the divide between ICE and EV? Jim Anderton doesn’t think so, and describes another way to engineer a workable solution.
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So much has been written about electric cars that I’m almost reluctant to add my comments about them.
Almost.
But there is an elephant in the room regarding electric cars—and for some reason, no one seems to be talking about it: Range.
Electric cars are expensive, but they are dropping in price—mainly thanks to major government incentives. Many people will use those incentives to take a serious look at EV’s, but for one-car families or single individuals, the simple reality is that a single vehicle has to do everything the owner needs it to do. In America, that means a combination of grocery shopping, commuting and the occasional long-distance trip. Perhaps occasional towing.
This uniquely American use of the automobile, for short trips and for long hauls, means that American consumers tend to default to larger, more comfortable and capable vehicles. They pay the price for this in higher fuel consumption in stop-and-go driving. With the current state of technology, electric vehicles are ideal for commuting. However, despite optimistic claims to the contrary, long-distance driving—and especially towing—is very difficult to do in an electric vehicle with the current state of EV charging infrastructure.
People who attempt to do this plan their trips around the charging stops, and they assume that the chargers will be operational and available when they get there. If the weather is cold, however, range drops significantly.
From an engineering perspective, there is a dirty secret in automotive propulsion: the power needed to accelerate the mass to cruising speed is significantly higher than the power needed to maintain it at that speed. To get adequate acceleration in a modern light vehicle, it is typical for a midsize sedan to have 150 horsepower. But to maintain a highway cruising speed in that same sedan might require as little as 30 horsepower.
Hybrids get excellent fuel mileage by using the high torque of the electric motor to accelerate that mass, reducing the demand on the internal combustion engine. But that engine is sized to take over from a depleted battery, so is typically as large and thirsty as a pure internal combustion vehicle of the same size.
Here is what I would do:
Design a so-called pure EV, like the Tesla Model 3, and add a 30 horsepower two-cylinder internal combustion engine with an integral generator. Run it as a highway cruise range extender, driver selectable so that on long runs or when towing, the EV would be essentially range unlimited, allowing charging at the destination after a long highway run. That engine could also be used as a booster when towing or carrying heavy loads, and as a source of cabin heat in cold weather, further extending the battery’s range. A very small fuel capacity would be adequate, and the entire module could be packaged like a small generator set. It could even be modular, and perhaps dealer-installed into the front trunk or “frunk” common in electric vehicles. Another intriguing possibility is if this were designed as a drop-in module that could conceivably be leased, or even rented for vacations or long trips.
The key to this kind of hybrid is to not downsize the battery and use a large engine, as is done now, but to offer a real alternative to the many Americans that do not have easy access to home charging, are living cold climates, drive long distances, or some combination of those three.
How small of an engine could generate 30 horsepower? With current technology, a 400 cc unit—like a small motorcycle engine—would be adequate, and the powerplant could be designed with ignition and valve timing set for fixed RPMs steady-state operation for even greater efficiency.
That technology exists now, with all the world’s major motorcycle manufacturers. So why do manufacturers do this? One reason is ideological, because many EV proponents don’t like transitional technologies. Another is political, with many jurisdictions taxing or refusing to subsidize vehicles that burn any amount of gasoline. But the grim fact is, electric vehicles just don’t cut it for millions of drivers on the American continent. And a tiny, piston-powered auxiliary power unit could tip those drivers into the EV camp.
