While city dwellers may be used to railway crossings marked with
flashing red lights, the easier-to-miss warnings at rural crossings
often just consist of a sign. That's because there's no easy way of
providing electricity to such isolated locations. While solar panels
could provide part of the solution, a team of engineering students and
faculty at the University of Nebraska-Lincoln believe that photovoltaics
alone can't consistently provide enough power. Instead, they devised
several systems that harness power from the rails themselves.
Although wave energy-harvesting systems are often just presented as
concepts that may someday see actual use, one was recently deployed in
Hawaii to provide power to the municipal grid. Built by Northwest Energy
Innovations, the Azura device will remain in operation for a 12-month
assessment period, with an eye toward eventual commercialization.
With its large tidal range, Britain's Bristol Channel has a huge potential for generating tidal electric power. The problem is that, until now, schemes for tapping that power have required building dams and barrages so gigantic they would have given even the most wild-eyed Victorian engineer pause. As a more economical alternative, Kepler Energy has announced plans for a 30 MW tidal energy fence to be built in the Channel. With an estimated cost of £143 million (US$223 million), the underwater fence would be built in the water somewhere along the line between Aberthaw and Minehead and could be operational by 2021.