RENEWABLE ENERGY:

BECOMING YOUR OWN POWER COMPANY

25.

An Alternative Energy Vacation


The last few months have seen a flurry of activity concerning alternatively powered automobiles. Both Nissan and Toyota have announced the development of hybrid electric automobiles. The Toyota entry, named the Prius, is available for purchase now in Japan and will probably be made available in this country in the near future, most likely in the California market.

Both of these companies are using a technology that combines gasoline powered internal combustion engines with an electric power train to save mileage. The Toyota, for example, will use its battery power and electric motor in those situations where traditional IC (internal combustion) engines are the most inefficient. This includes situations like starting up from a stop, traveling at low speeds, or going downhill.

When more power is needed at higher speeds or on hills, the gasoline engine takes over, with the switch being "smooth and virtually imperceptible", according to a recent New York Times article. This results in an increase in fuel efficiency that gives the Prius a range of 300 miles at 66mpg, a significant increase over current mileage numbers. It also means that the vehicle, while taking advantage of some electric vehicle technology, will seem to operate just like a standard IC powered automobile.

Yet, even as the news media and the corporate marketing flacks tout this "new technology" of hybrid powered vehicles, the concept and application has been around for decades. Which brings us to the "alternative energy" vacation that Maggie and I took over Thanksgiving.

We took Amtrak from Denver to Seattle and spent some time on the Seattle waterfront and (through some serendipitously good weather) also got to cruise around Elliott Bay on the Washington State Ferry. It was while we were on the ferry that Maggie brought something to my attention that made me realize the "alternative" nature of our transportation.

She noticed the plaque on the wall of the ferry that described the boat and its inner workings. And wouldn’t you know it, the darn thing was powered by an electric motor. This boat, half the size of a city block, made its way around Puget Sound on electricity! Which made me realize that the train on which we had come across the country and the trolley we rode around the waterfront were also powered by electricity.

Now, electric trolleys have been pretty commonplace in large cities since early this century, but I hadn’t really connected electricity with the transcontinental railroad and certainly not with a ferry.

Anyone who has had any contact with trains has probably heard the term "diesel electric" used in conjunction with locomotives. I have, but had always focused on the "diesel" aspect without paying much attention to the "electric" part of the term.

A diesel/electric locomotive (like the Washington State Ferries) gets its motive power directly from large electric motors. The motors, in turn, draw their electricity from large diesel generators. At first glance this may seem like the addition of an unnecessary step in the process. After all, why not just run the things on the diesels and forget the additional electric motor?

But, remember the Toyota Prius? An IC engine is at its least efficient when pulling heavy loads, on hills, or at low speeds. Also, at different rpm’s, an IC engine provides different torque (force) to the wheels. This is why we have transmissions in our cars, so we don’t operate our IC engines at rpm’s that are too high or too low.

However, an electric motor delivers the same torque at all rpm’s, which is very efficient. Also, using an IC engine to run a generator means the IC engine can run at a constant speed regardless of the speed of the vehicle, which makes the engine much more efficient and its operating costs much lower.

Diesel/electric drive systems have been in constant use in this country since WWII for railroads, where their size and weight are not much of a problem. Yet, here we are listening to CNN tell us about this "new technology" that is half a century old.

There is nothing new here at all. About the only thing that the auto industry will have to do is scale down the concept to fit in the typical family sedan. Heck, these oversized Sport Utility Vehicles that have become so popular may actually be ideal candidates for early adoption of this technology to the automobile. They’re getting to be about the size of locomotives, after all.

The auto industry knows it has to do something but it is still feeling its way as to exactly what. CBS news just this past week quoted an industry executive as saying that "No car company will survive in the 21st century if it relies solely on the gas engine."

Though no car company has yet produced the automotive analogue to the power system in a locomotive (Toyota uses the gas engine to drive the wheels instead of a generator) it is only a matter of time before someone does. My bets are with the Japanese, those masters of miniaturization, to find a way to squeeze the locomotive power train under the hood of a car.

Also, these early attempts at hybrid car construction are still crude at best, what Amory Lovins of the Rocky Mountain Institute calls "tank conversions", where an existing chassis and drive train are converted. Lovins has long been a proponent of true hybrid "hypercars" that are designed from the ground up using light weight composites and aerodynamic design to squeeze the maximum mileage out of a gallon of fuel. Using his concept he projects fuel economies of 100 to 150 mpg.


All Contents © 1998
Wagonmaker Press
Thomas W. Elliot

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