In his 2003 State of the Union Address, President Bush announced that hydrogen would be America’s alternative energy source for the future, and he challenged Congress to appropriate funding for research and development to get the USA there. Like a lightening rod, his announcement electrified the alternate fuels community and charted a course amid otherwise uncertain energy times. With unreliable petroleum imports now topping 65 percent, OEMs are competing in the race to put sustainable hydrogen-powered vehicles on the streets.
People are asking how soon we’ll see hydrogen fuel-cell vehicles, and, more immediately, how do we make the transition from gasoline engines (ICE’s) to fuel cells? It is taking a variety of alternate fuels to usher in the hydrogen economy, making the outlook for these fuels no less promising than for hydrogen. For example, both natural gas pipelines and ethanol’s fledgling distribution infrastructure will serve us. Liquid ethanol (and also methanol) is a good “energy carrier” for storing, transporting and reforming to hydrogen.
Electricity, the cleanest alternative, is obviously used in both gasoline-electric hybrids and fuel cell vehicles and is used for electrolyzing water into hydrogen.
Let’s take a closer look at some of these alternate fuels and vehicles in the context of who’s competing and winning in the race to hydrogen.
Natural Gas (methane) is clean and plentiful (for now at least) and is certainly one of the winners among alternative fuel choices, thanks to a strong distribution (pipeline) infrastructure and strong trade support.
Compressed natural gas (CNG) has found favor among federal fleets (USPS), municipal fleets (buses, police cruisers, etc.) and private fleets (taxicabs, etc.) for both light and medium duty vehicles. The population of registered natural gas vehicles (NGVs) has grown to an estimated 130,000 operating in the U.S. every day. Some say growth has flattened, however, as fleet owners switch back and forth from gasoline/diesel to CNG, prompted by fluctuating fuel prices, equipment problems (due to poor fuel system integration), and incremental costs.
Installation costs for compressor and fill sites can be high as well. On the other hand, operators of indoor vehicles have taken note of the clean air benefits of CNG, and some are switching over from propane.
Liquefied natural gas (LNG) is successfully being used to power medium and heavy-duty vehicle applications like refuse haulers and line-haul trucks. Natural gas is also used for producing propane, for liquid fuels, and is itself a prime source for hydrogen.
LPG/Propane could be a winner among motorfuel alternatives—if you can find the fuel, and at competitive motorfuel prices. Propane vehicles have been around for years, and propane is a favorite for bi-fuel or dedicated light and medium duty vehicles of all sorts, with just under 300,000 vehicles in service as of last year. Propane is also the fuel of choice for many non-road vehicles. An estimated 95 percent of the nearly 500,000 forklifts in use run on propane,3 not to mention tugs, ice sweepers, etc. The Propane Vehicle Council touts propane as the “Exceptional Energy” choice, and if a nation-wide propane vehicle-refueling infrastructure ever materializes, they could be right.
Ethanol/E85 could become a real winner, too, being well promoted by trade associations and seen as a viable alternative to gasoline in the agricultural corn belt of America.
Ethanol markets have grown tenfold (about 10 million gallons a year) during the past five years; admittedly 98 percent of the ethanol presently produced is used as the additive in E10 (Gasohol). Ethanol is a good energy carrier for reforming into hydrogen, once fuel cell vehicles arrive.
Ethanol flexible-fuel vehicles (FFVs), which are conventional ICE vehicles with provisions for alcohol use, will play a winning role in distations in the U.S. The Department of Energy (DOE) and original equipment manufacturers (OEs) have joined forces to develop E85 markets in six major areas including Denver, Chicago, and Minneapolis. Many more motorists would likely opt for using ethanol if refueling stations were accessible and cost-per-mile prices were made more competitive with gasoline.
Biodiesel, made principally from soybeans or recycled vegetable oils and fats, has more recently been recognized as meeting federal EPAct mandates when used as B20 (20 percent splash blended) or neat (100 percent). Bio is a winning alternative fuel for diesel engines, although older engines may require fuel system modifications, since bio could cause seals to deteriorate. OE warranties generally accept up to five percent biodiesel blended with petrodiesel. The market for biodiesel is now small, and bio prices are about 30 percent more expensive than petrodiesel. Biodiesel markets are expected to grow to over 40 million gallons this year. Presently over 100 major fleets use biodiesel; many are federal government agencies like NASA, the National Park Service, and the military.
However, municipalities using biodiesel realize benefits because bio offers an inexpensive way to meet their EPAct mandates (and help clean the air).
Electricity is an excellent clean and sustainable energy carrier. Emissions are low as fossil fuel emissions are scrubbed at the source, or even zero when solar, wind, or hydro (river or tidal) power is used to generate it. But electricity is expensive to transport (via the “grid”) and even more difficult to store. It serves as an auxiliary power source when used with gasoline in hybrids.
Battery Electric Vehicles (BEVs) have evolved greatly from simple DC motor golf carts, but high vehicle costs and limited battery capacity still limit BEVs to a range of 100 miles or so. Making things worse, advanced-battery problems like heating/cooling issues forced some OEs to revert to heavier leadacid batteries, which adds more weight and reduces vehicle range further. The 10 percent zeroemission-vehicle mandates
in California that championed BEVs have since been rewritten, and OEs have been canceling leasing programs. The good news? BEVs have proven themselves in “niche markets” serving municipalities, gated communities, stopand-go delivery fleets and as commuter cars. Plus, BEV technology transfers readily to hybrid-electric vehicles (HEVs).
And The Winner Is…
Hybrid Electric Vehicles!
Today’s HEVs are early models for tomorrow’s hydrogen-electric fuel cell vehicles, and clearly lead the race as the most practical near-term answer for reducing and eliminating petroleum use. Today’s gasolineelectric hybrids have a miserly fuel appetite and are rated super ultra low emission (SULEV) and partial zero emission (P-ZEV) for their ultra clean emissions. Smaller passenger vehicles benefit most from being “hybridized” as do urban stopand-go transit buses, refuse haulers, and other such vehicles. These heavier hybrid applications use ethanol, clean diesel, natural gas and propane powered ICEs, or even propane micro-turbines, in conjunction with a variety of innovative electric drivetrain configurations. Biomass-ethanol FFV hybrids are proposed by some6 as the best way to turn off the oil-importation spigot, but we haven’t seen any of these on the OE horizon. Nonetheless, expect to see a large variety and number of gasoline-electric hybrids to enter markets soon in the race to hydrogen.
The race for advanced transportation technologies and hydrogen is definitely on and the course is clearly defined. Edward B. Cohen, Honda’s VP of Government and Industry Relations, describes it best when he cites Honda’s three-fold vision for R&D and marketing:
Clearly these are exciting times: automotive history is being written before our eyes. As the alternatives to petroleum jockey for market position, we as technicians can do our part by supporting the leaders in the race to fuel cell vehicles and, ultimately, a hydrogen economy.
What are Hybrids?
In the hybrid, electricity is generated and stored in battery modules, or ultra-capacitors, which serve as “electric superchargers” to augment ICE power under load. Hybrid electric vehicles (HEVs) typically get 25–40 percent (or more) better economy and lower emissions thanks to engines that are “super tuned” for peak volumetric efficiency and clean performance. Atkinson Cycle variable intake valve timing (Toyota – VVTi) technology and continuously variable transmissions (CVTs) help keep engines running at their most efficient speeds to achieve superlow emissions (SULEV). Regenerative coasting and braking add to already impressive MPG, vehicle performance, and range.
Various HEV drive configurations are possible—series, parallel, full, partial, through-the-road, etc. In a “full hybrid” vehicle like the Toyota Prius and the Ford Escape, the engine shuts off at low vehicle speeds for zero emissions (or for stealth operation in military vehicles.) Full hybrids qualify as SULEV and P-ZEV vehicles. Partial hybrid vehicle engines, as used in the Honda Insight or Civic, don’t shut off when under way. The OEs will be offering increasing numbers of hybrids soon, but so-called “plug-in hybrids” being tested in Europe are not likely here for some time.
Hybrids’ Presence Grows
Environmentally friendly vehicles are gaining in popularity, seeing a 54-fold increase in popularity in the past five years, according to an R. L. Polk & Co. study done in 2003. Gasoline-electric hybrid-electric vehicles (HEVs) accounted for nearly 83 percent of green vehicles registered in 2002. Toyota’s Prius led with approximately 17,500 registrations, and Honda’s hybrid Civic had nearly 10,000. Hybrid-electric vehicle sales are expected to grow by over 2000% over the next ten years.
Source: Rob Rodriguez (ASE)