Marking Earth Day

Linda saw an article that there would be several displays, live music, and food on the Court Avenue Bridge to celebrate Earth Day this year. We did get to enjoy a little live music and saw a number of familiar food vendors but the hour was a little early to be eating so we stuck mostly to the displays. I shot photos of two of the displays.

One display showed several toy cars powered by photovoltaic cells like the one in the photo. As you can see, someone got creative and powered an ear of corn. It was a cloudy day so the power was not quite enough to drive the vehicles forward... unless you shone a flashlight on them.

The other display in the photo is another electric vehicle. The Nevada School District brought their hybrid school bus to display. Linda and I chatted with the two men and learned that Sigourney School District also has a hybrid school bus. These buses are battery powered while speeds are below thirty miles per hour and have a braking system that regenerates electricity as they come to a stop. When more power is needed, the regular engine kicks in and powers the bus up to highway speeds. With a range of about thirty miles on the electric system, the bus is able to complete the normal route. They also shared that gravel roads seem to put an added drain on the electrical system; I didn't ask but got the impression that wheel spin starting and skidding when stopping probably steal away a portion of the power. When the route is completed, the bus is plugged in to recharge the batteries. Nevada plans to move their bus from the rural routes to more town miles; they may not even fire the engine during a run.

Iowa State University's chapter of the Society of Automotive Engineers had their car on display as well. Designed under a special set of rules, their car would compete with others from around the nation. Each vehicle will be evaluated on several measures. There are four actual racing events: acceleration, cornering, endurance, and autocross. The endurance race is 13.7 miles and cars can reach highway speeds. The autocross sounded more like a tight half-mile road course with plenty of twists and turns that keep the speeds down under thirty miles per hour. Besides the racing, recognition is also given for other criteria like low production cost.

Alliant Energy was also on site promoting efficiency and alternative energy sources. One I'd not heard of was biodigesters. The idea is to capture the methane being released when biological material is digested by microbes.

Anaerobic digestion ... produces a methane and carbon dioxide rich biogas suitable for energy production helping replace fossil fuels. - Wikipedia

There's an interesting but fairly technical article available on the Alliant Energy website. In it, they state the the annual return for six hundred dairy cows could be two thousand dollars but that one thousand cows increases that return to twenty-eight thousand dollars; not bad! Their research and statistics show that they're getting one kilowatt hour per five cattle or per hundred pigs. It really is an interesting read... if you find that kind of thing interesting... and I kinda do.