Not too long ago the car makers where competing with each other on performance—mainly measured by horsepower and acceleration. Fuel economy did not have high attention in the benchmarks for premium cars. This has changed recently and fuel economy is suddenly a major trait that every OEM has on its list.
This trend was not only driven by environmental regulations of various governments but the fuel price itself. Also consumer behaviors have changed a lot and our society is undergoing a paradigm change with regards to our transportation concepts and mobility behavior.
These days more and more new car customers are looking at the datasheets and specifications for fuel consumption and emissions. The prestige and image of many cars are now largely driven by its benchmark fuel efficiency and emission values rather the pure horsepower backed driving performance and acceleration. So this changing consumer behavior and the strong government involvement via rules, regulations and incentives for environmentally friendly cars leads the automotive market towards a new generation of cars to satisfy this trend of “green transportation”. And that’s the main reason why hybrid-electric Vehicles (HEVs) are showing up in every fleet and product line of the major car manufacturers.
What we often forget, especially here in the U.S., is that fuel efficiency and low emissions are not only achieved via revolutionary game-changing technologies like the emission-free electric powertrain of a hybrid vehicle. Looking at the fuel efficiency of currently available or shortly announced HEVs, you would be surprised that this fuel efficiency can be pretty closely matched by a modern diesel engine using state-of-the-art direct fuel injection systems and an electronically controlled and well optimized motor control unit. The big difference comes with the price "bump up" for the technology that the buyer pays.
A diesel engine typically adds only moderat cost compared to a comparable gasoline engine (in the range of approximately $1-2,000). The price adder of HEVs vs their traditional standard combustion engine version is normally at least 2-3 times as high. The reason for this is that hybrid-electric vehicles need to incorporate a complete electric powertrain plus all the energy management and storage systems, a high voltage battery, and plenty of electric systems like inverter, converter, and charger applications into the vehicle architecture.
Therefore the additional electronic content in a HEV is much higher than the little electronics in the motor control unit plus some diagnostic and monitoring sensors which are needed to build a very efficient direct fuel injection system for a modern diesel aggregate in a much more cost effective way.
Checking the numbers
Let’s look at the table below, which shows the average highway fuel consumption in miles/gallon of HEVs vs diesel. There is not much difference between similar sized and powered diesel and HEV cars. The emission values of those cars are also in a comparable range. Only the pure city consumption of the HEVs seems to be superior since the HEV-engine typically shuts down (so called start-stop mode) every time the car is stopped in a traffic jam or at red lights. But adding relatively low cost start-stop functionality to a regular diesel engine (so called micro-hybrid) would push the diesel city mileage likely into the same range as the one advertised for gasoline-HEVs.
Looking at these numbers the diesel solutions could offer quite some threat to the penetration of HEVs. In countries in Europe where diesel is a well established engine type and the consumer acceptance is at least as high for gasoline powered aggregates we see already a very strong market penetration of diesel while HEVs seem to sell much harder compared to U.S. or Japan, for example.
I drove a Citroen 1.2L Diesel in Spain more like 15 years ago. At the time, one of my other cars had a Chevy 350 cu in (that's about 5.7L for you kids). At first, I though I might as well get out and walk. But once I figured out that I couldn't shift it like an American sports car, the Citroen and I came to a pleasant understanding: it was a wonderful, if small, car. Bell hops at the hotels would ask me where I was from, how I liked the car, and usually, what I drove at home in the US. I would tell them that my engine at home was 5 times as large, and some would wonder at my Spanish: once, a fellow said "Chevy?" and I smiled yes... it was fun.
I miss that car: it was well built, and I couldn't complain of the fuel economy. I wouldn't buy a hybrid: for one thing, I tend to tow a trailer once in a while, and my tastes run to an FJ Cruiser, but I'd certainly consider a large-enough vehicle with a Diesel powerplant.
I drive one of the Citroen babies (1.2L turbo-deisel) 5 years ago in Spain for several weeks over 4000Km; less than 4L/100km doing 120Km/hr. Experience: smooth, powerful, miserly like US automakers / customers don't have a clue.
We don't get out enough nor realize the joke we are. Thanks for your article and quiet significant observation.
ps: did you ever have to change one of those HEV batteries, do you know how often you have to in the car's life & related $, any idea of that environmental overall impact? Time to look at the numbers (all of them including 'electric vehicles').
I also converted/drove a Natural Gas conversion dual fuel minivan; a local after-market update shop on a Pontiac minivan. Technology easily applied ($2500) after mfg. and paid-for using a local sales-tax rebate, that is developed to production levels in Italy (over .5M NG vehicles in use). I can gas-up at home with a compressor appliance outside my garage. Engine life is extended with higher octane rating / cleaner burn. Gasoline is still there with a dash-mounted switch.
It's out there, just get to it. Good hunting .. & travelling.
I think HEVs will benefit once solar has dropped in cost to the point that consumers have excess power and need a place to put it.
I drive a Jetta TDI myself, powered by B100 biodiesel produced from recycled fryer oil.
Nice profile of the potential of diesel. And, fortunately, given that as the author states, his company wins with wide-spread adoption of either diesel or HEV, I'm betting this is more balanced than so much of what we read on the subject these days.
I think it is important to have a lot of research going into HEV and pure electrics, and we need early-adopter purchases, but in the near-term, the planet could probably get the best reduction in fuels use and pollutants per buck by looking to solutions like modern diesel and super efficient gas power plants. I wonder how much fuel we could save simply by reducing the horsepower in all vehicles by ten or twenty percent.
That's probably the real hold-up. We want power and lots of it. To satisfy that desire, we have big gas engines and hybrids that are more about increasing horsepower than fuel economy.
David Patterson, known for his pioneering research that led to RAID, clusters and more, is part of a team at UC Berkeley that recently made its RISC-V processor architecture an open source hardware offering. We talk with Patterson and one of his colleagues behind the effort about the opportunities they see, what new kinds of designs they hope to enable and what it means for today’s commercial processor giants such as Intel, ARM and Imagination Technologies.