Tuesday, August 21, 2007

Alternative Wheels

There has been a lot of talk lately about alternative fuels for transportation, particularly George Bush's hydrogen economy and Portland's Biofuels law that recently took effect last week... but what about alternative transportation?

Sure, here in Portland we've got bicycles, buses, MAX, streetcar, aerial tram, and not to mention a pretty decent walking environment.

However, while our streets are filled with hybrid Priuses, motorcycles, and scooters galore - the vast majority of people in our city are still commuting via single-occupancy vehicles. In case you haven't heard, using a three or four thousand pound chunk of plastic and steel (up to 5-10,000 pounds for SUVs like the Hummer, Land Rover, or Mercedes G55) to transport yourself and a few bags of groceries a mile or two from the grocery store isn't exactly the most efficient means of transportation: the majority of the energy in the gasoline burned in your engine is used to move the vehicle and air condition the vehicle, not actually move you.

Unfortunately, this means that for the average person in the US, a large percentage of the energy used in transportation (gas burned in your car) is essentially wasted. What if we could simply drive more efficient cars?

As you may have heard recently, Congress recently passed a new set of CAFE standards, designed to legislate an improvement in manufacturer's overall fuel efficiency in the cars they sell. Although this topic is probably better covered by some of the other transportation blogs, suffice it to say that the improvements are too little, too late - and are not likely to be too effective: whereas in Europe they promote fuel efficiency by massive gas taxes, cheap gas in the US has encouraged car manufacturers to waste the efficiencies they have gained in engine and drivetrain technologies by simply increasing the power of the cars they make. As a result, fuel efficiencies in American cars has actually decreased overall since about 1988.

Although there are a growing number of motorcycles and scooters on the streets of Portland today, all but the die-hards will choose to garage them during the winter months. So although they win the gasoline fuel efficiency contest, they will probably never become a primary transportation option for most people due to exposure to the elements while riding. And trust me, I know well from experience! There's nothing like having to don rain pants, jacket, and gloves before each ride - it is somewhat constricting on your winter wardrobe.

There are alternative, efficient vehicles that are now in development that are something of an automobile/scooter hybrid - achieving high fuel efficiences coupled with climate protection:

Enter the Tango

The Tango, a small electric car developed by Commuter Cars, a company based in Spokane Washington, is an extremely narrow vehicle. It features a jet-fighter like cockpit arrangement (driver sits in front of the passenger, not beside) - even narrower than some motorcycles (some jurisdictions even allow the vehicle to lane-split).

Its specs are even more impressive: with a top speed of 150 mph and 0-60mph time of 4 seconds, it will beat the pants off of most cars on the road - although, at its current cost of around $100,000, it is equally priced - although different versions are planned to be released at more affordable price points.

The specs:
  • Width: 39 inches (~99 cm)
  • Length: 101 inches (~257 cm)
  • Weight: 3000+ lb (1360+ kg)
  • 0–60 mph (0–96 km/h): 4 seconds
  • ¼ mile (0.4 km): 12 seconds @ 120 mph (193 km/h)
  • Top speed: 150 mph (240 km/h)
  • Range: 60–80 miles (96–128 km) (Lead-acid batteries)
  • full charge from a dryer outlet (220 volt) in 3 hours; 80% charge in 1 hour

Personally, however, I wouldn't mind driving the Carver - even though its slower and uses an internal combustion engine, it sure looks like a lot of fun to drive!

maybe its just the rockin' jamiroquai tune tho?

Of course, the ultimate in efficiencies for transportation in urban areas would be won by dramatically expanded and improved mass transit in conjunction with safer and expanded bicycle facilities, such as bike lanes. However, we're going to need all the help we can get in curbing global warming.

The Hydrogen Hoax

Read an excellent article on the feasibility of the Hydrogen economy, written by a person whom I consider somewhat of a genius: Robert Zubrin, an aerospace engineer whose qualifications include "a B.A. in Mathematics from the University of Rochester (1974), a masters degree in Aeronatics and Astronautics, a masters degree in Nuclear Engineer, and a Ph.D. in Nuclear Engineering — all from the University of Washington." [wiki]

The Hydrogen Hoax

The science-based argument states how inefficient the hydrogen production process is, while also pointing out that there is no viable way of efficiently storing liquified hydrogen or compressed hydrogen. In fact, according to Zubrin, to store 20 kg of hydrogen (comparable to 20 gallons of gasoline), would require either a 70-gallon cryogenic tank, or a 162 gallon tank at 5,000 PSI tank - the compressed hydrogen gas tank along would weigh approximately 2,800 pounds (without the 20 kilograms of fuel); the cryogenic storage tank would be prone to failure due to the nature of cryogenic hydrogen, which causes metal fatigue and brittleness and 'boils off,' which could be a serious safety issue in confined quarters (such as parking garages).

The most important points he puts forth, however, are the inefficiency of burning hydrogen as compared to gasoline (hydrogen has a lower energy density); as well as the need to produce hydrogen - as 100% of the hydrogen on the planet earth is already bound up in chemical compounds... requiring enormous amounts of energy to free up the hydrogen from these bonds:

The spokesmen for the hydrogen hoax claim that hydrogen will be manufactured from water via electrolysis. It is certainly possible to make hydrogen this way, but it is very expensive—so much so, that only four percent of all hydrogen currently produced in the United States is produced in this manner. The rest is made by breaking down hydrocarbons, through processes like pyrolysis of natural gas or steam reforming of coal.

Dispensed in compressed gas cylinders to retail customers, the current price of commercial grade hydrogen is about $100 per kilogram. For comparison, a kilogram of hydrogen contains about the same amount of energy as a gallon of gasoline.

...then he gets down to the actual chemical reactions used commercially to change hydrocarbons to pure hydrogen, and the extra energy needed to compress or refrigeration to cryogenic temperatures - which could sap up to 40% of the original energy potential in the original hydrocarbons. As for hydrogen production via electrolysis - where would the energy come from? Pick your poison: coal or nuclear.