Progress Report No. 6 - Germany: innovation for the coming e-highway

The e-highway of the future is being tested in Germany.

Germany has been looking for new ways to enhance its goals for a carbon neutral environment. Today there is a 6.2-mile stretch of highway for testing the viability of an overhead power transmission line to power cargo trucks electrically. The energy use will be half of the conventional diesel fuel and the emissions are zero from the truck, according to the Siemens Company, the engineering firm behind it all.
​The e-highway of the future is being tested in Germany.
However, this is only a test. A test using the “Autobahn” between Darmstadt and Frankfort for the next three years to determine its suitability for future transportation on a more universal scale. Siemens has been testing off-road for years prior to implementing the Autobahn directly at an unused airfield outside of Berlin.
Darmstadt Technical University will collect data of the ecological and economic impact in real time of this “test strip” on the Autobahn. The motivation behind this project is to eliminate the exhaust produced by large cargo vehicles in congested areas and to reduce the dependency on foreign oil. This power grid will charge the on-board batteries during longer hauls.

How it works
It’s similar to a trolley car but with some twists.
We’ve all know the famed trolley cars of San Francisco. You may have noticed a flexible X-shaped device that connects between the top of the trolley and the overhead power lines. It looks like the X you see on each side of a large baby carriage. This X device is called a pantograph. It connects the electricity from the power lines to the trolley car. This powers the electric motors that drive the trolley cars. Here starts the twists: Trolley cars have a set pattern determined by the rails they travel on. They generally travel at between 15-30 mph. They do not need to be steered as they are guided by the permanently installed rails. They do not have to continually connect, disconnect and reconnect with the power supply.
Because trolleys go slow on a predetermined path it makes the control much easier and the overall design so much simpler. Therefore maintenance is greatly reduced and more easily accessed.
Not so with the new e-highway infrastructure and the trucks. These trucks must be multi-fueled, in this case diesel and electric. They must have a more robust pantograph. A pantograph that can sense where the overhead power lines are at 55 miles per hour. The pantograph also must sense the alignment needed to attach and detach at highway speed.
The infrastructure is everything for this project. It requires a very sturdy overhead power line that has to be resilient in all kinds of weather — not only wind, snow, ice and rain but also hot and cold. The reason temperature is so critical is that the power lines have temperature constants that apply to the wire’s expansion and contraction. In hot weather those lines will expand and cause drooping, and in the winter the lines will contract, becoming taut. The drooping may make the connections and the surface contact for electrical conduction difficult and inefficient while in extremely cold weather the line could snap upon access. Also it is necessary for these wires to have structural support for icing.
You may recall the James Bay Project, a 30 Gigawatt hydroproject where the wire support towers went down like dominoes during the ice storm of 1998. The wire drew taught from the cold, and the weather conditions were just right for an ice buildup that caused line after line to snap or take down these huge towers. This would be a catastrophe for a power line, laying down on a highway, with 690 volts at the end of the cable.
The next big problem is synchronizing the power surge as multiple trucks get “on line” (as it were). I have contacted Siemens regarding this and their public relations person is on vacation until Monday, the day after this column will run, so I will report back as a footnote in my next column.
Next is the issue of traffic. So the overhead power must accommodate any sudden change in traffic. When power of this magnitude is turned on or off repeatedly and — unlike our trolley cars — unpredictably and instantaneously it puts an enormous strain on the source and the conductors on the pantograph. This means that the power sources must be conditioned to handle this which adds to the cost and taxes the reliability of the system long-term. I have worked with Siemens high-power equipment and have been impressed with its innovation, performance and reliability. If anyone can do it, it’s Siemens.
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In conclusion
There is much more I would like to comment on, as Germany is experiencing a large transition in its infrastructure due to the need to accommodate an ever-increasing number of vehicles using its highways.
Germany, as a large metropolitan country, has the highest percentage of renewable energy as the sum total of national energy consumption at roughly 36%. It was first in creating the early infrastructure, though it came at great cost. Now, Germany will have to refinance its new infrastructure first before any of the e-highway becomes mainstream. This would have to be accompanied by corporations changing their fleets completely over to hybrid systems. This could only be done gradually.
There is always that risk that something new and better will come along. The Germans, in terms of the best of “extreme” technical innovations, have been first. The problem is being first has its downside. This is where Germany has run into problems. Successful initial technologies are always expanded upon and improved both in quality and cost. Solar panels for commercial use have doubled in output in the last 30 years and have reduced in costs from over 10.00/watt to under .75 watt. So being first is not always best. This is every industry’s nightmare: When to embrace the latest technology. I hope for the best in the e-highway, but I do see some severe limitations long-term.
I can only hope otherwise for Germany. If the country is successful, all of us will benefit.
Remember America’s attempt at a similar innovation was started with the High Speed Train Act. It was signed into law in 1965. I promise not to make fun of Amtrack — Amtrack the train of yesterday meeting the needs of the people of the day before. I’m sorry I just couldn’t resist.

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