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Preserving Venice by boarding a hybrid vaporetto with MG’s batteries

When visiting the beautiful city of Venice there are to ways to get around: on foot or by water. In case the former is no option, a vaporetto is the way to go. It’s Italian for water bus and a large fleet makes up a public transport network for the city and province, transferring hundreds and thousands of passengers each day, from the mainland across the lagoon, through the canals and to the nearby islands.

The increase of tourists and therefor transportation has a dangerous impact on the delicate environment of the lagoon in general and the canals in particular, with many precious historic buildings on their banks. The constant navigation and frequent manoeuvring generates a lot of waves and washing water, which in turn leads to progressive erosion of their foundations, draining them of sand and clay.

Operating conditions of a vaporetto are very particular. Due to the many stops, congested traffic, varying speed limits and timetable optimisation their navigation pattern show high acceleration and deceleration performances. The heavy sequence of stop-an-go transitions requires a very irregular power supply. When supplied directly by a generator, this would lead to high diesel consumption and high exhaust emissions.

Enter Liuto: an acronym for Low Impact Urban Transport water Omnibus. It’s a vaporetto with a low resistance hull and a hybrid energy solution, designed around two decades ago. The 300kW Siemens propulsion system used to be powered by lead-acid battery pack, which in turn was charged by a diesel generator running at constant speed. This way the engine could operate at its optimum efficiency level, minimising fuel consumption, pollutant emissions, vibrations and noise.

At the time the hydrodynamic impact was reduced by the optimised hull and propeller, while the hybrid energy solution was a good compromise between technical, economic and environmental requirements. Recently its lead-acid battery bank has been upgraded to MG’s RS batteries, two strings of eight modules each, controlled by a HV Master. Together they operate as peak power supply and energy buffer, under very high but short charge/discharge power levels.

This is what our RS Series excel at. Compared to traditional lead-acid batteries these lithium-ion modules can take in and push out a large amount of power in a short time. Liquid thermal management keeps the battery cells on temperature, to improve performance and extend cycle life. A redundant BMS, a unique cell-to-cell propagation protection and a built-in fire suppression mechanism take safety to the next level. As an added advantage they’re compact and lightweight.

Compared to steel or aluminium vessels with traditional propulsion systems Liuto is a beautiful example of a more efficient, more economic and more ecological solution even in a challenging application such as urban water transport. It generates less wave motion pollution, less air pollution and increases comfort for all passengers. Now it’s ready to serve another decade while protecting the delicate and valuable context of Venice and its lagoon, for both tourist and inhabitants alike.

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Sealegs charges into the future with amphibious craft on renewable energy

Sealegs is a world leaders in amphibious crafts, designed and developed to take all the hassle out of boat launching and retrieval. The system simply drives from a storage location, down a boat ramp or beach and into the water. Once afloat, the wheels lift up out of the water to be stored against the hull, and the boat is used as normal.

The company has been driving the amphibious boating revolution since its start in 2001. The very first versions had electric motors driving the wheels, while across the rest of its models hydraulic propulsion is powered by a petrol engine. But the E4 combines high-torque brushless electric motors with MG’s high density 7kWh lithium battery technology. In many ways it may be the best Sealegs craft yet.

Without a petrol engine roaring the E4 is quieter, but runs faster and longer than conventional models. With a standard 150hp outboard it achieves 40 knots, while it drives for around 1.5 hours on a land, depending on speed, load and terrain. Performance is further increased by regenerative braking and outboard charging. All the usual safety features, such as emergency braking, are included.

Without having to accommodate a petrol engine, there’s more flexibility to house the 51 V 7 kWh lithium ion battery, which takes four to five hours to fully recharge, by simply plugging it into a 240 V mains supply. The outboard also feeds the battery via the VSR and a PowrFlow step-up charger, as does the regenerative braking system. Solar power is another option. All systems are connected to a central Naviop display which supports MG’s battery systems to show battery status.

Combining of the latest battery and motor technology quite possibly represents the future of amphibious boating. “The release of the Electric E4 takes Sealegs’ global leadership position in amphibious technology to the next level,” according to Founder and Chief Technology Officer Maurice Bryham. “We have made our amphibious system 33% faster, 60% quieter and 50% more powerful.”

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