SOLAR BOATS then n now

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HISTORY OF ELECTRIC BOATS



While a significant majority of water vessels are powered by diesel engines, with sail power and gasoline engines also remaining popular, boats powered by electricity have been used for over 120 years. Electric boats were very popular from the 1880s until the 1920s, when the internal combustion engine took dominance. Since the energy crises of the 1970s, interest in this quiet and potentially renewable marine energy source has been increasing steadily again, especially as solar cells became available, for the first time making possible motorboats with an infinite range like sailboats. The first practical solar boat was probably constructed in 1975 in England.

The first electric boat was developed by Moritz von Jacobi in 1839 in St Petersburg, Russia - a 24-foot (7.3 m) boat which carried 14 passengers at 3 mph. It was successfully demonstrated to Emperor Nicholas I of Russia on the Neva River.

It took more than 30 years of battery and motor development before they began to be deployed in any numbers. In 1886 an electric boat crossed the English Channel both ways in 8 hours. By 1889 the first 6 electric charter boats were working on the Thames and in the 1893 Chicago World Fair 55 carried more than a million passengers.

Electric boats had an early period of popularity between around 1890 and 1920, before the emergence of the internal combustion engine drove them out of most applications. For example, an 1893 pleasure map of the Thames shows 8 "charging stations for electric launches" between Kew (Strand-on-the-Green) and Reading (Caversham).

Most of the electric boats of this era were small passenger boats on non-tidal waters at a time when the only power alternative was steam. One of the largest in Britain, and the only surviving example, is the Mary Gordon which was built on the Thames for Leeds City Council for use on the Roundhay Park Lake. It was 52 feet (16 m) long and could take 75 passengers, and is now being restored.

In a few situations, the use of electric boats has persisted from the early 20th century to the present day. One of these is on the Königssee lake, near Berchtesgaden in south-eastern Germany. Here the lake is considered so environmentally sensitive that steam and motor boats have been prohibited since 1909. Instead the Bayerische Seenschifffahrt company and its predecessors have operated a fleet of electric launches to provide a public passenger service on the lake.

In the US, the Electric Boat Company was founded in 1899 and built the first submarine purchased by the U.S. Navy in 1900. Since then, electric power has been used almost exclusively for powering submarines underwater, although diesel was used for powering them on the surface until the development of diesel-electric transmission by the US Navy in 1928. The Electric Boat Company eventually became General Dynamics Corporation in 1952.

The use of combined fuel and electric propulsion has gradually been extended over the years to the extent that some modern liners such as the Queen Mary 2 use only electric motors, powered by diesel and gas turbine engines. The advantages include being able to run the fuel engines at an optimal speed at all times and being able to mount the electric motor in a pod which may be rotated by 360° for increased manoeuvrability.

The use of electricity alone to power boats stagnated apart from their outboard use as trolling motors until the Duffy Electric Boat Company of California started mass producing small electric craft in 1968. Duffy Boats has produced over 10,000 electric powered boats to date and is producing well over 300 per year today. It wasn't until the 1980s that the Electric Boat Association was formed and solar powered boats started to emerge.

liens divers :

http://www.ibtimes.co.uk/solar-powered-boat-capable-20kph-invented-by-vietnamese-farmers-1505437