If you're a skeptic about electric servo drives, the Tokyo plastics show would have made you a believer.

If you're a skeptic about electric servo drives, the Tokyo plastics show would have made you a believer. The International Plastics Fair (IPF '99) in September was busy, but it was the quietest show I've seen. The loudest sound was the blast of an air blow-off nozzle on a mold, or possibly the swish of a pneumatic sprue picker. That's because over 60% of the injection machines on display were all-electric.

It seemed a futuristic fantasy by U.S. standards, since I'd guess that only 10-12% of the injection presses sold here this year are electric driven. But the future has already arrived in Japan. Spokesmen for Toshiba, Sumitomo, and JSW told me that 40% of the Japanese market in sizes under 300 tons was all-electric last year and might hit 60-70% this year. A more sober estimate from Tsukasa Yoda, president of Nissei, pegs current Japanese sales of electric machines at 20-30% of the overall market, a share he predicts could hit 50% in two or three years.

In Japan, electric servos also drive 80-85% of the robots sold today, according to a Kawaguchi source. He says the comparable figure in the U.S. is 10-15%, though he believes it could go to 40-50% in a few years. And in blow molding, a Tahara spokesman says electric machines account for 30-40% of Japanese sales, compared with almost nothing in this country. (We'll look into the potential for all-electric blow molding in next month's cover story.)

Electric machines in Japan are 20-40% more expensive than hydraulic presses, just as they are here. But a clue to their raging success there is that the average cost of electricity is 18¢/kwh, versus around 6.5¢ here. Besides being quiet, clean, and highly precise, electric machines save 30-50% or even more of energy cost.