Blending Technologies for the Future
by John D. White - Technology Correspondent
Competition among energy sources marks the march of technology through history. A mixture of muscles, water, and wind has powered mills and pumps since Roman times. New England's textile mills displaced hand spinning and weaving, relying into the 20th century on an abundance of steeply falling streams.
Beginning in the 1800s stationary steam engines slowly emerged as a feasible backup for gravity-powered water. Times of drought or extreme cold curtailed waterpower so much that the vast network of looms sometimes fell silent. To reduce losses, mill owners began to rely on costly reciprocating steam engines to supplement the cheap waterpower. When the flow became plentiful again, steam engines were idled to save money.
Tandem energy sources have long characterized other industries. Horse-drawn milk wagons shared roads with gasoline powered trucks for decades. Steam, diesel and even electric locomotives ran on the same tracks. Coal, oil, and natural gas furnaces heated adjoining houses along urban streets for half a century. Propeller planes, turboprops, jets, and even helicopters still land at the same airports around the world.
Changes in Automobile Power
"Plastics!" was the single word of advice for the future given to a young man in the movie The Graduate. At risk of oversimplifying in a similar way, the single word for the future of automobiles may be "Hybrids!"
Multi-fuel piston engines promise a revolution almost as great as that of the internal combustion engine a century ago. The least ambitious change incorporates ability to burn a variety of fuels besides gasoline -- propane, alcohol, hydrogen, or natural gas -- in conventional piston engines. This change promises cleaner, more economical, efficient, and longer-working engines.
Fuel cells to power buses, trucks, and automobiles have passed beta testing and appear ready for the commercial market. To replace imported petroleum fuel, either natural gas or methanol derived from it enjoys support from a number of major oil companies, prominent inventor Marshall Bricklin, Senator Jay Rockefeller (D-WV), as well as General Motors, Daimler-Chrysler and Ford. The latter two auto makers have cooperated with a Canadian maker of fuel cells, Ballard Power Systems, Inc., to run a test fleet of fuel-cell buses in Chicago and Vancouver, B. C. Caltech's Jet Propulsion Lab and a joint venture between Georgetown University and United Technologies now explore still other approaches to fuel-cell vehicles.
Battery-powered automobiles have shown appeal throughout the century. Very quiet running, their smooth but brisk acceleration appeals to almost anyone. They emit no noxious fumes and literally turn off while waiting at stoplights. However, sales remain small because two problems persist: heavy batteries and limited cruising range. The latter difficulty links to another problem, long charging times for massive battery packs.
Fleet vehicles at large industrial sites have employed this approach since the 1930s, but on public roads electric cars comprise a smaller fraction of traffic than they did before World War I. Visionaries a generation ago predicted facilities in which banks of charged batteries would be swapped for discharged ones in less than the time to fill a gas tank. These facilities, sited at gasoline stations, would recharge with cheap power from various sources. They could use discounted off-peak electricity from utilities overnight; solar collectors during the day; and wind generators around the clock. Another dream involved parking meters in which commuters could pay to plug in and charge their batteries while shopping or working a shift. Neither developed, however.
Hybrid fuel-electric cars, a new generation of vehicles in final design stages, may change the picture. They would use batteries for quick acceleration and quiet operation. Small, quiet, and clean onboard generators operating at efficient speeds would charge the batteries en route, prolonging the initial range. After the car stops in the parking lot, the generators continue to run as long as needed to charge the batteries for the return trip. Where available, fee-based plug-in charging stations could "refuel" the car even more cheaply than the auxiliary engine could. Separate units isolated from the propulsion system can provide lighting, heating, and air conditioning.
Sewage Yields Clean Fuel
Waste management offers another example of hybrid technology. Fuel cell technology supplies electricity on the space shuttle. Cells from the same manufacturer, Connecticut-based ONSI Corporation, now convert into energy the hazardous and smelly gaseous effluent from a sewage treatment plant in Yonkers, New York.
An article in the 7 February 1998 issue of The New York Times (p. 46) reported on its successful first year of operation. Over 20 tons of methane supplied the 200 kilowatts of power needed to supply 60 average homes. The chemical reaction of the fuel cell employs hydrogen from other fuels, such as gasoline, as well as methane. The operation produces almost none of the oxides of nitrogen, sulfur, and carbon found in the exhaust of internal combustion engines or incinerator chimneys. Hot water, the only by-product, has many uses. Methane from decomposing garbage in landfills provides similar opportunity for disposing of a dangerous waste product cleanly by generating electricity.
The Yonkers plant had long used methane from 90 million gallons of wastewater daily to fuel conventional engines and boilers. The plant produces enough surplus gas -- that might otherwise have been flared off -- to supply an additional fuel cell. The extra power can be sold to the regional grid. Thus the Yonkers unit reduces greenhouse gas emissions while paying for itself.
In 1899 there surely were many thinkers as imaginative as Jules Verne or Buckminister Fuller. Despite the existing rail and telegraph systems, none predicted with reasonable accuracy the 20th century's communications or travel networks. A narrowed focus helps society perfect existing systems, but provides little incentive for great leaps of progress. In 1899 most people favored enforcement of cleanup after one's horses as the answer to fly-borne disease and pollution. Few imagined that in their lifetime the horse would vanish entirely from their streets. No one forecast a different form of air pollution that would result from that rare toy, the automobile.
Lighter, longer-lasting batteries and expanded use of fuel cells offer the possibility of altering the next century as much as the internal combustion engine and computer have changed this one. The piston-driven liquid fuel engine, dominant for three generations, may go the way of the surrey, the ox cart, and the steam locomotive. Leonardo da Vinci and the Wright brothers did not conceive of the airliner, but they might have if the power plant had been available. Who will now dare to predict the effect of fuel cells? Each home could generate its own electricity while heating its water. Fuel cells allow placement of the powerplant almost anywhere in an automobile, leading to radical design changes.
Ironically, Henry Ford predicted an automobile revolution propelled by alcohol fuels, but cheap petroleum from East Texas forced him to reconsider. With current fuel cells consuming methanol, his expectation may come true a century later.
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