Venice's water taxis may be going green

Venice's water taxis may be go...
Water taxis in the city of Venice
Water taxis in the city of Venice
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Water taxis in the city of Venice
Water taxis in the city of Venice

Although most people likely associate Venice with gondoliers quietly poling their boats along the canals, the city is also home to approximately 550 motorized water taxis. These watercraft are all equipped with diesel engines that spew exhaust and make a racket, creating both air and noise pollution. With this situation in mind, engineers from University of Southampton spin-off company REAPsystems are developing hybrid engines that could be swapped in.

The diesel-electric engines can reportedly "be installed by any boat builder and fitted into all existing boats."

When moving at slow speeds within the city center, the engines can be run in a quiet and clean electric-only mode. Once the taxis reach higher speeds, however, the diesel automatically cuts in as the main source of propulsion. In this mode, the electric motor switches over to act as a generator, charging its lithium-ion battery pack and allowing the diesel to operate more efficiently.

Plans call for one of the engines to be tested in a boat in Venice this summer.

"The benefits are clear: no noise, no pollution, no vibrations when operating in the city," says Southampton's Prof. Suleiman Sharkh. "Our demonstration with the water taxi will inform the local authorities, so they can tighten their regulations. Thus, the reduced maintenance cost and the halved fuel consumption will convince operators to switch to these green engines."

REAPsystems is currently raising funds for the project, on Indiegogo.

Sources: University of Southampton, REAPsystems

It needs to be considered whether there claims of efficiency and reduced pollution hold up. Like most hybrid solutions, the energy for the electrical propulsion appears to be gained from fossil fuels. While this may gain some economy in that the electrical system is only charged when the Internal Combustion motor (ICM) is operating at more efficient speeds, the conversion from mechanical to electrical to chemical and back wastes some of that efficiency. In addition to that the ICM has to be oversized to provide both motive power and power to charge the batteries at the same time. This adds to the weight that needs to be accelerated, and unlike land based transport, recovery of that energy on slowing would be extremely inefficient due to the liquid nature of water. How this hybrid system would be more efficient would have to be questionable. That it is less polluting in the city appears obvious, until you consider that the pollution is just moved a little further away, and then discharged into the atmosphere. The pollution is not reduced, just dispersed over a greater area.
@Higlandboy....all good points. The main thing though is that closer in to the city, noise pollution should be significantly reduced. That ALONE is worth it. In 20 years all these things will be fully electric. For now we still have to deal with the polluting ways of the ICE. It's had a great run, but luckily it's coming to an end.
Let's hope that VW is not providing the diesel engines.