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Honda and Nissan Consider Plug-in Hybrids –  April 28, 2009

Honda and Nissan have been banking on fuel cells and electric cars as the long-term strategy for sustainable mobility. Company executives are now warming up to plug-in hybrids.

Since their introduction in the US in late 1999, hybrid cars have been repeatedly dismissed as a “bridge technology”—a euphemism for a short-lived second-rate technology that briefly serves a purpose until it can be replaced with something better and longer lasting. But in recent statements coming within days of one another, executives from Honda and Nissan are reconsidering the role that hybrids will play in the coming decades.

Honda began leasing a limited number of its FCX Clarity hydrogen fuel cell cars last year, and still sees hydrogen as the long-term alternative to gasoline. However, for the first time, Honda executives are now speaking of hybrids and plug-in hybrids as a mainstream technology with staying power. Nissan is also beginning to consider plug-in hybrids.

For both companies, the plug-in hybrid is seen as the next stage of hybrids and as the key to the technology’s longevity. Honda was banking on a transition to fuel cell cars, while Nissan was primarily moving toward the pure battery-electric vehicle.

Honda began leasing a limited number of its FCX Clarity hydrogen fuel cell cars last year, and still sees hydrogen as the long-term alternative to gasoline. But Honda President Takeo Fukui believes that the cost of fuel will need to increase before hydrogen-powered cars are ready for significant growth. In an interview published by Bloomberg, he said, “Oil prices are going to go up. When that time comes, fuel cells, solar panels, hydrogen, those will be the key words. We will have packages that will be very competitive at that time.” In the meantime, he said the company is “thinking about plug-in hybrids.” He added, “We aren’t thinking about commercializing one right away.” Honda will need to modify its current mild hybrid system—or develop a new approach—in order to produce plug-in hybrids.

The Bridge Gets Much Longer

Honda’s views on plug-in hybrids are also motivated by new consumer tax credits—as much as $7,500 for a robust plug-in hybrid. Fukui said, “We understand the situation, in terms of government and incentives. Naturally, we’re going to have to accommodate that too.”

Nissan also sees a future jump in oil prices as the key to its long-term efficient technology: the electric car. “When GDP growth comes back on a worldwide basis, there will be again attention on the oil market, which will trigger an oil price increase,” said Carlos Tavares, Nissan executive vice president. “We will be in the right tempo to face that environment.”

Mark Perry, Nissan product planner, told, “Zero emission vehicles are clearly our focus and we believe it’s the future state of transportation. Some segments of the market in the near term may best be served by high efficiency internal combustion engines, diesels, hybrids or extended range electric vehicles [also known as plug-in hybrids].” He added that these technologies are “all bridge technologies to the time when battery electric vehicles and fuel cell vehicles can cover every market segment.”

The Key Question: When?

The key question for both companies is how long it will take until electric cars and fuel cell vehicles can reach levels approaching the current hybrid market. After 10 years on the market, hybrids represent less than 3 percent of the new car market.

Speaking at the Society of Automotive Engineers’ 2009 World Congress last week, Minoru Shinohara, Nissan corporate senior vice president, said that plug-in hybrids will be an important transition solution to the pure electric vehicle because they don’t need an extensive public charging infrastructure. The cost of building the public charging infrastructure will cost many billions of dollars; therefore, most analysts believe that it could take decades to construct.

Hybrids will not necessarily disappear even after an electric-recharging or hydrogen-refueling infrastructure is built. Kenji Nakano, senior chief engineer, Honda R&D, also appearing at the World Congress, said, “Hybrid technology is also applied to fuel cell vehicles, range-extender vehicles, and plug-in hybrid vehicles. Thus, instead of being a bridge technology, hybrids are expected to remain in the mainstream for quite some time.”

Breakthrough to Advance Hydrogen Car Production

Alternative Energy – 20 April 2009

One of the main hurdles in the field of hydrogen car research is the development of a good fueling system. Professor Issam Mudawar along with his research team has developed a hydrogen storage system that would allow a car tank to be filled in five minutes and you can drive on that fuel for 300 miles.

But turning the above abstract idea into a reality was not a cakewalk for the project team which is funded by the General Motors Corporations. The biggest obstacle was the problem of heating while one is refueling the tank. According to Issam Mudawar who is the Purdue University (PU) Professor of Mechanical Engineering , “The hydride produces an enormous amount of heat. It would take a minimum of 40 minutes to fill the tank without cooling, and that would be entirely impractical.”

These hard facts posed a great challenge to the Purdue University research team. The heat effect has to be countered and the time limit for refill has to be shorter. For refueling they have used a very fine powder, known as metal hydride. This powder absorbs hydrogen very efficiently but can’t do anything regarding the release of huge amount of heat. Therefore a very good cooling system at all the refueling station is of vital importance.

The research team was working on a solution which can do something substantial concerning heating. They needed accessory connectors that can work at the same time to take away the heat while refueling process was on. So the researchers have to overcome this hurdle and design an efficient heat exchanger. They have to be a pioneer in the field because no one had treaded on that path before.

Keeping the complications in mind the team has developed a system where metal hydride is placed in small “pockets” inside a pressure chamber. They injected hydrogen in pressure compartments and it gets absorbed. But the wonderful thing is this reaction is reversible. Therefore the hydrogen gas is released from the metal hydride by lessening the pressure in the storage vessel. They fixed the heat exchanger inside the hydrogen storage pressure vessel.

Mudawar explains, “Due to space constraints, it is essential that the heat exchanger occupies the least volume to maximize room for hydrogen storage.” The cooling system utilizes the regular automotive coolant which flows inside a U shaped tube between the pressure chamber and the aluminum heat exchanger. The exchanger is designed in such a way that when the hydrogen enters into the metal hydride, a smooth temperature absorption mechanism starts functioning. Darsh Kumar, a researcher at General Motors Corporation is hopeful, “As newer and better metal hydrides are developed by research teams worldwide, the heat exchanger design will provide a ready solution for the automobile industry.”

Hydrogen Fuel From Non-food Sources

February 21st, 2009 – Alternative Energy

Tomorrow our vehicles may derive power by enzymes. These enzymes may originate from the cellulose of woodchips or grass and instead of emitting poisonous gases they will exhale hydrogen. We know that when hydrogen is burned, the only emission it makes is water vapor, so a key benefit of hydrogen fuel is that when burned, carbon dioxide (CO2) is not produced. Clearly, hydrogen is less of a pollutant in the air because it omits little tail pipe pollution. Hydrogen also has the potential to run a fuel-cell engine with better effectiveness over an internal combustion engine.

A team of scientists from Virginia Tech, Oak Ridge National Laboratory, and the University of Georgia says it has successfully generated hydrogen gas. Normally these kinds of fuels are derived from starch. Jonathan Mielenz, who is the leader of the Bioconversion Science and Technology Group at ORNL, says, “It is exciting because using cellulose instead of starch expands the renewable resource for producing hydrogen to include biomass.”

This hydrogen gas is clean enough to power a fuel cell by combining 14 enzymes, one coenzyme, cellulosic materials from non-eatable sources, and water heated to about 90 degrees Fahrenheit (32 C). The researchers utilized cellulosic materials which is isolated from wood chips. But researches also claim that crop waste or switchgrass could also be used for this purpose. These research outcomes are being published in ChemSusChem. The research is supported by the Air Force Office of Scientific Research; Zhang’s DuPont Young Professor Award, and the U.S. Department of Energy.

Percival Zhang who is assistant professor of biological systems engineering in the College of Agriculture and Life Sciences at Virginia Tech, states, “In addition to converting the chemical energy from the sugar, the process also converts the low-temperature thermal energy into high-quality hydrogen energy – like Prometheus stealing fire.” This group declares the benefits of their “one pot” process. The first advantage is they are using a unique combination of enzymes. The second advantage is that hydrogen generation rate is as fast as natural hydrogen fermentation. The third advantage is the chemical energy output is greater than the chemical energy stored in sugars. The maximum hydrogen yield is produced from the cellulosic materials.

Percival Zhang said that if we can utilize a small fraction (two or three percent) of annual biomass production (at global level) for sugar-to-hydrogen fuel cells for transportation, it can lead us to transformational fuel independence. For U.S.A. the figure varies a bit. If U.S. wants to get rid of fossil fuels from transport they actually need to convert about 10 percent of biomass – which would be 1.3 billion tons of usable biomass.