I average 18mph (burst of up to 30mph) on a7 mile ride and I have never been unable to hear approaching cars from behind. Do I trust my ears alone? No. But I've never been surprised by Prius, Volt, Tesla Roadster, or any other hybrid or electric vehicles. In biking events or on bike paths I can even hear approaching bicycles from behind (bike chain, wind, and tire noise). So I'm surprised that wind noise overpowers car noises for you.
It's been interesting to see all the comments about this! Obviously it's struck a nerve...and danger aside, I'm happy to see a number of people less than thrilled about the idea of noisier hybrids and EVs. There has to be a better solution.
The 1865 act required all road locomotives, which included automobiles, to travel at a maximum of 4 mph (6 km/h) in the country and 2 mph (3 km/h) in towns and have a crew of three travel, one of whom should carry a red flag walking 60 yards (55 m) ahead of each vehicle.
Backup audible warning is already implemented on most trucks, commercial vehicles, municipal vehicles, etc. That is not a bad idea; the driver has limited view, and risk is higher. But that is totally different than always on noise generators.
For decades, engineers have worked to combat erosion by developing high-strength alloys, composites, and surface coatings. However, in a new paper, a team at Jilin University in China turned to one of the most deadly animals in the world for inspiration -- the yellow fat-backed scorpion.
Green energy is being billed as a way to make communities that are energy deprived more self-sustaining. So it makes sense to use natural materials to create devices that harvest this type of energy. That’s the idea behind a hybrid wind/solar energy harvester made of bamboo that’s been developed by UVM researchers.
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