issue: September 2009 APPLIANCE Magazine APPLIANCE Engineer - The Open Door The Next Breakthrough in Microwaves?

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Bob Schiffmann, owner, R.F. Schiffmann Associates Inc. Ingenuity is a crazy thing. Sometimes it leads to innovative products that look good on paper and make engineers giddy, but more often than not, these products get lost on consumers and end up in the niche wasteland. Take the Polara refrigerated oven, which Whirlpool debuted way back in 2002, as an example. The concept—developing an oven that keeps food cool until a preset timer tells it to start cooking—is beyond innovative, but consumers were obviously not ready for it. Or, at $1800, just couldn’t afford it.

But once in a while a product that appears to be nothing more than a late-night infomercial ends up transforming an industry. I think the Heinz Beanzawave is one of those products. At the very least, I believe this appliance will be the impetus for a major change in the microwave oven market.

While it is still in the concept stage and is currently just a prototype, the implications are profound for the entire microwave oven and component industries. Measuring just 7.4 in. tall by 2.6 in. wide by 5.9 in. deep, the Heinz Beanzawave oven is the smallest domestic microwave oven I’ve ever seen. It uses a rechargeable lithium ion battery to power an all solid-state microwave oven. It plugs into the USB port of a computer, using the computer’s software to control the oven. The concept is to give people the ability to heat up a snack or lunch (i.e., baked beans) at their desk. But I think there is more to the story. After all, how exciting is a baked-bean oven?

The product replaces the magnetron and its power supply with high power transistors! No more magnetron, transformer, diode, and capacitor. The commercial implications are huge: lightweight, portable microwave ovens, even for your car, that use significantly less steel, aluminum, and copper. These are important benefits for our greening society. Also, coupling efficiency is likely to be close to 100%, far surpassing the approximately 50% energy conversion efficiency seen in today’s standard magnetrons.

From a technical, as well as practical, point of view, this technology is best suited for conventionally sized countertop and over-the-range microwave ovens. Since it is likely that the selection of transistors would be governed by the industrial, scientific, and medical (ISM) radio band requirements, the frequency of choice would remain 2.45 GHz. This, in turn, favors larger-cavity ovens that can allow for multiple modes for better cooking uniformity.

Other new design features could also be introduced. For example, since less space would be required for the area now occupied by the power supply, the cavity could be made significantly wider. Then, by moving the touch-pad controls from the side panel to the front face of the microwave, a back-and-forth shuttling platform could replace the ubiquitous turntable. Such a platform would provide extra convenience for the homemaker, allowing the use of large rectangular cookware, which currently is prohibited because their size prevents it from turning within current ovens. The larger cavity would also allow users to cook larger dishes such as poultry. It may even be possible to divide the cavity into fast-cook and slow-cook sections, each fed by its own transistors to provide the high and low power needed by each section. The opportunities seem boundless and exciting.

So how practical is it? Will it become a reality? It’s still basically only an idea, and has an impractically high projected selling price of $160 for a 250-W oven, largely because of the high price of these transistors. Of course, 250 W would be sufficient to heat that little tub of baked beans, but to heat a cup of coffee might take 4 or 5 minutes (or more) rather than the 1½–2 minutes consumers have come to expect.

But here’s the thing: Those high transistor prices will come down. In a recent New Yorker article (July 29, 2009), Malcolm Gladwell, in reviewing Chris Anderson’s book, Free: the Future of a Radical Price, noted that the price of a single transistor was $10 in 1968, $5 in 1963, and $1 in 1961. And it gets lower. According to Anderson, today one can purchase 2 billion transistors for $1100—that’s $0.000055 each. That’s a major price decline.

What drove those price declines was largely the sales of computers. InfoTechTrends estimates that 2008 computer sales in the United States was 111.4 million units. Compare that with microwave oven sales of approximately 10 million units that same year. Is that enough to produce a major decline in transistor prices? That remains to be seen, but keep in mind that the transistor cost doesn’t have to match the cost of only the magnetron. Really, it needs to match the price of replacing the magnetron plus all the other components as well, and with the additional cost of the rechargeable battery.

Yes, my 40-plus years in this industry tells me this little bean oven is going to revolutionize the microwave industry. It will happen; I’m just not sure when.

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