Hydrogen: Which Path to Take?
By Bill Moore
There are basically two ways to get to a hydrogen-powered vehicle future according to a recent study commissioned by the British government. The Department of Transportation hired Ricardo Consulting Engineers to look for the best pathway to get to a hydrogen fuel future. They came up with two possible approaches, one that involves a major, early committment to hydrogen and the other which takes a less ambitious hybridization strategy.
What the study discovered may surprise you.
It turns out that the more evolutionary pathway of gradual hybridization actually produces faster results at less cost than the hydrogen pathway. In its 187-page report entitled, "Carbon to Hydrogen Roadmaps for Passenger Cars", Ricardo Consulting concludes -- among other things -- that "progressive electrification and hybridisation offers significant CO2 benefits regardless of the fuel or its source, at a risk level more manageable than alternatives such as more radical new vehicle technologies or major infrastructure change."
[To download UK report, right click link and "SAVE AS"].
The study is obviously important in its implications not only to the British automotive industry but also its American, Japanese and European counterparts. The Bush Administration has apparently thrown its support behind hydrogen as the fuel of the future, which is commendable, offering to spend $1.7 billion on the FreedomCAR program, successor to the PNGV effort of the Clinton presidency, and another $1.2 billion over five years to what was initially called the Freedom Fuel program for hydrogen research. Subsequent trademark issues forced the Administration to abandon the name, but not the effort, at least for now. Some pundits have suggested that when the costs and technical barriers are fully appreciated, Congress will not be well disposed to fund the initiative, but that is yet to be seen.
What the British study demonstrates is that while hydrogen may well eventually assume its role as the fuel of the future, perhaps sometime around the 2020 to 2030 time frame, the industry and consumers are more likely to follow the hybridization route for numerous reason including cost and product acceptability.
The Ricardo report looked at the latest in advanced automotive technology from publicly-available industry studies to its own considerable internal documentation, analyzing the applicability of each and their potential contribution to reducing CO2, the principle objective of the exercise. The technologies evaluated included various degrees of hybridization and architectures, solid oxide fuel cell batteries, hydrogen-fueled internal combustion engines, fuel cells and more. Costs and producibility were also studied.
As quickly becomes apparent from the Well-to-Wheels Vs. Time for Both Routes to Hydrogen graph, if your goal is to rapidly begin to reduce CO2 emissions, the Low-Carbon Route using evolving hybridization is clearly the way to go. Switching to an accelerated hydrogen fuel pathway where the first vehicle's use modified internal combustion engines and automatic start/stop systems, which is considered the first step in the Hydrogen Priority Route, will actually create more CO2, not less. The reason is that the hydrogen used to fuel the vehicle will have to come from stream-reformed natural gas.
Ricardo Engineering calculated that the Well-to-Wheel grams per kilometer of CO2 generated would increase by 29.5% to 189 above the standard base ICE model, a Ford Focus meeting Euro 5 emission standards. Fuel consumption was estimated at 2.27kg/100km of hydrogen. They projected that such a vehicle could be available by around 2008.
By contrast, about the same time, phase two "hybrids" with 42-volt starter/motor/generators and VRLA batteries would be generating 40 grams less of CO2 per kilometer. And it would cost about 100 pound sterling less than the hydrogen-ICE vehicle at 16,450 pounds. The CO2 emissions gap between the two pathways remains fairly consistently wide until about 2015, when CO2 improvements possible through the Low-Carbon route begin to level out and fuel cell stacks move from powering APUs on the vehicle to powering the vehicle, itself.
By 2020, there is very little difference between the two in terms of CO2 emissions because Ricardo only considered stream-reformed hydrogen in their analysis. They felt that other, more benign, renewable forms of hydrogen were simply too far out to make sound economic projections.
Ricardo also ignored the role of early hybrid vehicles like the Prius and Insight because they viewed these as small niche vehicles which have sold, up to this point, in only very small numbers compared to current automotive production volumes. They deliberately took a very conservative approach to the technology starting with a simple belt-driven auto start/stop engine system, moving steadily on to a 42V system with regen braking and then to an integrated 42V, mild-hybrid architecture, with the first mass-produced parallel hybrids appearing about 2012.
They explain that they did this for essentially two reasons: acknowledgement of the conservative nature of both the auto industry and the average consumer. Carmakers are extremely hesitant to make radical jumps in technology -- with GM's revolutionary EV1 being one of the very few exceptions, and consumers are reluctant to invest hard-earned dollars in what they feel might be unproven technology.
Ricardo acknowledged that while early adapters would be willing to risk buying into the technology, most people wouldn't. Their report stresses over and over again that each new technological innovation must be preceded by technology customers are familiar with. The aim is to gradually introduce more innovative technologies in digestible bits and pieces. Above all else, there must be no readily apparent difference from one technology to the next. Once owners are comfortable with the notion of auto stop/start, they will more readily accept regen braking, etc.
For those of us who easily made the leap into parallel hybrids like the Prius and Insight, we might argue that this is being just a bit too deliberate and plodding, but the good news is the industry appears to have accepted the concept of a Low-Carbon pathway, not-with-standing the FreedomCAR, Freedom Fuel initiatives announced by the US federal government. The long list of hybrid announcements over the last several months strongly suggest that we are heading down the right pathway.
The 187-page Ricardo report is a gold mine of information on advanced vehicle technologies and well worth spending a few hours studying. We've archived a copy on EVWorld.
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