Science Ano Industry

WITH the second UN Conference on the Peaceful Uses of Atomic Energy held at Geneva in September, attention has been focused on the progress of the nuclear power programs of Russia, Great Britain, and the United States.

Five American atomic-powered plants are now actually producing electricity, with a rated capacity of about 73,000 kilowatts. Four are small ones, ranging from a 300-kw. homogeneous reactor to a 5000-kw. boiling-water reactor. The only plant of any size is the 60,000-kw. reactor at Shippingsport, Pennsylvania. It is owned by the AEC, which invested approximately $98,400,000 in it. Duquesne Light Company, which manages the plant and built the conventional generator system that uses the power produced by the reactor, invested $22,500,000. Westinghouse Electric, which built the plant, invested $500,000. The power is sold as steam to Duquesne.

Six other large atomic power plants are either building or under contract for privately owned electrical systems. Three, in Chicago, Detroit, and New England, range in size from 134,000 to 180,000 kw. A fourth plant near New York will combine nuclear power with an oil-fired plant to superheat the steam and permit more efficient operation; the nuclear-power output is rated at 163,000 kw. These four are scheduled to be finished by 1960. Two additional plants of about 60,000-kw. capacity each are to be built near Sioux Falls, South Dakota, and Eureka, California, and are to be completed by 1962.

Together these six plants will cost about $323 million. Although all will be privately owned, all but one will receive financial help from the AEC, which in most cases picks up the bill for research and development costs and supplies nuclear fuel for the first few years without charge. A seventh plant is a 75,000-kw. reactor for the publicly owned Consumers Power District in Nebraska. Finally, the AEC itself is building an experimental fast-breeder reactor in Idaho with a rating of 15,000 kw., to bring the total capacity to about 790,000 kw.

In overall capacity and in the size of individual power plants, this program is surpassed by developments overseas. A 400,000-kw. atomic power station with four reactors is under construction in Russia, while Britain is building a 500,000-kw., two-reactor plant. In contrast, we have no multiple-reactor plants under consideration.

But if the American program is in some ways smaller than developments overseas, it is outstanding in other directions—particularly in the wide variety of reactors now building or proposed. The four big British piles now building are all improved versions of the Calder Hall type. Our nine big reactors already built or being built cover at least five major types, and even more varieties are found in those piles still in the planning stage.

This is the result of American eagerness to explore the various possible kinds of reactors. Most atomic reactors have three main elements: the fuel, a moderator to slow up neutrons so that fission takes place, and a coolant that removes heat energy from the pile to make steam. In all three cases, a reactor designer must choose among several possible materials. His fuel can be natural uranium, uranium “enriched" by varying quantities of its fissionable isotope, or plutonium. His moderator can be graphite, pure water, heavy water, beryllium, or with some designs a moderator is not necessary. The coolant can be air, a gas such as carbon dioxide or helium, pressurized water, boiling water, or molten sodium metal.

Even this list does not exhaust the possibilities. To be sure, not every material can be used with every other, but many combinations are possible. Because the United States is in no immediate need of new power sources, we can afford to explore these combinations in order to find the most efficient and economical type of reactor before embarking on a big building program. The British program is equally logical for that country’s needs a large supply of new energy as quickly as possible.

The American program is also distinctive in that it is being carried out primarily by private industry, with the AEC concentrating on research and development. Not everyone is agreed that in the present pioneering stages private industry will be able to handle the job. In particular, spokesmen for organized labor and publicly owned power systems have urged that the government itself should build large nuclear power plants.

These critics are also disturbed by the fact that although four small reactors for electrical cooperatives or small municipal systems have AEC approval, work on none has started. The reasons for this are not quite clear, but the case of the Wolverine Rural Cooperative Project, planned to be built near Big Rapids, Michigan, shows some of the difficulties. According to testimony before a congressional committee, the original price quoted on the aqueous homogeneous burner reactor desired was about $3,780,000. By January, 1957, it had climbed to $4,890,000. By the next August it soared fantastically to $14,436,000, and here the manufacturer withdrew his bid entirely because of price uncertainty.

Of course, the American atomic energy program is not designed solely for the internal needs of the United States. It is intended not only to supply leadership and data for other countries, but also to encourage the development of a reactor-manufacturing industry that will sell its products overseas.

When it comes to exporting reactors, however, one aspect of our atomic power program poses a difficult problem: in the course of our military atomic production, we have developed facilities to produce large quantities of the fissionable uranium isotope that, added to natural uranium, creates a more efficient fuel than natural uranium alone. Because we have this capacity, most of our reactors are designed to use “enriched” uranium. Today, however, the United States is the only source of such isotopes for countries buying our reactors, and they would have to depend on our good will to maintain their supply of fuel. This is a serious deterrent to a prospective customer.

Behind the comparatively relaxed tempo of the American atomic energy program is the fact that the United States is still luxuriating in a plentiful supply of fossil fuels. This happy situation is not going to last a great deal longer. American experts at the Geneva Conference estimated that the overall energy needs of the United States are increasing 3 per cent a year, with the demand for electric power climbing 7 per cent annually. On this basis they predict that the usable fuel reserves in the United States recoverable at twice the present cost will last only fifty years more, with the cost of all fossil fuels zooming before thirty years are out.

The automatic car

One control stick for steering, throttle, and brakes is the big feature of General Motors’ newest experimental gas-turbine car, the Firebird III. The Unicontrol stick—reminiscent of the joy stick of early airplanes— is set at the driver’s hand in the center of the car. To steer, you push the stick to right or left. To step on the gas, you push it forward. To jam on the brakes, you pull it back. And to shift gears to reverse or neutral, you rotate the stick handle.

This one-hand control system is combined with an automatic steering device, which unfortunately can be used only on automatic highways still unbuilt. The Autoguide takes over to follow a low-frequency powered cable in the highway, relieving the driver of all steering duties. A touch on another button puts an automatic throttle — Cruise Control — into operation. Presumably at this point the driver curls up with a good book and relaxes for the rest of the trip.

Other unusual features of the car are of more immediate practicality. It has, for example, two engines: the 225-hp gas turbine that propels it, and a small 10-hp aluminum piston engine that drives all the accessories. The turbine, though 10 per cent more powerful than its predecessor in Firebird II, uses 25 per cent less fuel. The small engine drives a 100-volt, 60-cycle generator that can be plugged in, if desired, to power household appliances.

The fluorescent headlights go on automatically when it gets dark— in case the driver has dozed off over his book. An ultrasonic key opens the doors with sound waves from fifteen feet away. The headrests and footrests of the contour seats are power operated. Wheel and brake drums are combined in a single aluminum-alloy casting, designed to pull in air to cool the drum. A timer can be set to cool or heat the car’s interior ahead of time so that it will be completely comfortable when you step in.

The screwworm fly

The screwworm fly, which breeds and feeds on the open wounds of animals, has been killing or maiming livestock in the southeast for twentyfive years, to the tune of $10 million in Florida alone in 1957. Government entomologists are now trying by means of atomic radiation to breed this livestock parasite out of existence in the state of Florida.

Exploiting the fact that the female mates only once in her lifetime, U.S. Department of Agriculture scientists arc flooding 50,000 square miles with laboratory-bred male flies made sterile by exposure to gamma rays from radioactive cobalt. Observation has shown that the females mate as readily with sterile laboratory males as with others, and that sterilization of the male flies does not affect their sexual vigor. Thus if two sterile males are released for every normal male, the new generation should be 50 per cent smaller than normal. Continued over a number of generations — each generation is three to four weeks — this process should eventually reduce to zero the number of screwworm fly eggs hatching in the entire area.

This past summer, 50 million sterile flies a week have been dropped from airplanes over all of Florida and parts of southern Georgia and Alabama. An ingenious aspect of the program is that the male insects seek out female insects —as insecticides, chemicals, or bacterial organisms would not — for genetic destruction.

Growing 50 million sterile screwworm flies a week is no easy job. Insect experts have set up a mechanized fly hatchery in a remodeled aircraft hangar at Hendricks Field, Florida. Nearly all operations are automatic, synchronized with the fly’s life cycle from egg to adult. About 75,000 pounds of meat a week are needed as a growing medium.

It is too soon to see the results, but government entomologists are confident of the success of their two-year program. A pilot-plant experiment on Curaçao completely wiped out the screwworm flies on this Caribbean island. Now projects are afoot to use the technique on other insect pests, such as the Mediterranean fruit fly in Hawaii and the tsetse fly in Africa.

Smog

Smog is bad not only for people but for crops. Southern California growers estimate that it does $5 million damage a year. Now, however, a special spray has been concocted to help vegetation resist its effect.

Called Ozoban by Pfizer, which has put it on the market, the compound is an antioxidant. When sprayed on the leaves, it enters the plant cells and helps the plant resist the poisonous effects of ozone and other oxidized hydrocarbons found in the smog. Developed by scientists at the University of California’s Agricultural Experiment Station, Ozoban has been used on such plants as pinto beans, romaine lettuce, celery, and ornamental flowers.

Mechanizing the mail

Alert philatelists will have observed something new in traditionally conservative British postage stamps — an occasional stamp with mysterious black lines on the gummed side. These lines are evidence of the march of automation. At the Southampton post office, three machines are under test that will eventually be linked up to produce an almost completely mechanized system of sorting mail.

First in line is a “segregator” that sorts incoming mail according to size and bulk. The machine carries the mail automatically into a long revolving drum that acts like a huge sieve, letters slipping through narrowslots onto a moving belt below, while small packages, newspapers, and magazines are carried to the end for special handling. The letters are automatically separated a second time according to size.

Next step is a machine that faces the mail — one of the most difficult jobs to mechanize. Here is where the special stamps come in. The black lines, which appear only on stamps sold in the Southampton postal area, are graphite. In the facing machine the letters pass between the elements of several high-voltage scanners. When the stamp is in the right position for cancellation, the graphite lines complete the circuit; otherwise the letter is turned over automatically. By varying the number of graphite lines for some denominations, the mail can be further sorted according to class.

A mechanized destination sorter completes the process. This one is not completely automatic: an operator sits at a simple keyboard watching the letters as they drop down into a little window in the machine on their way to a moving endless belt. Using a standard two-digit code for any one of 120 postal areas, the operator punches for each address the appropriate keys that will release the envelope from the belt into its area compartment. The operator can sort nearly 6000 letters an hour, faster than the deftest clerk’s handsorting.

The British Post Office has already reached a state of efficiency that seems remarkable to most Americans. All mail is delivered overnight between any two points not on the extreme ends of the island. The first delivery is completed by 9:15 in the morning. And the mail service shows a profit.