At the recent event Electric Vehicles Land Sea Air in Stuttgart Germany, there was strong coverage of electric boats. Joachim Kopf of Kopf Solarschiff described inland boats relying partly or wholly on conventional crystalline silicon including bendable versions and lead acid batteries but with lithium-ion starting to be specified. A diesel solar hybrid with 300 km range has been supplied to Africa.
Andreas Kinlimann of Grove Boats gave the history of electric boats from 1830. Grove Boats helped with the Turanor now going around the world on solar alone- no sails. We heard it before - "Energy storage is our main problem". A secondary problem is the brittle crystalline silicon cells. Earlier trials on flexible photovoltaics did not give the required life. The crystalline cells break and they work inefficiently when hot. Three hybrids are considered to be available- expensive Steyr series diesel generator , in-line diesel, electric motor, transmission and just a separate large generator and Grove Boats uses the latter. They have looked at fuel cells but find them "inappropriate". Integration of components in electric boats is troublesome. Large solar boats tend to be more efficient. Range extenders and supercapacitors are of interest.
The extensive discussion after these presentations revealed that these boat companies are not in contact with the suppliers of the latest flexible photovoltaics or movement harvesting manufacturers. There are lessons to be earned from glider autonomous underwater vehicles with their multi-mode energy harvesting and the PV companies demonstration rollable PV sails for example. Asked about life of PV and other components required on the boats, they said that lead acid batteries are a pain to customers because of only a few years life. Ten years is required on PV, batteries etc. Flexible copper indium gallium diselenide should provide this. These people need to talk.
For more attend Electric Vehicles Land Sea Air USA 2011.
Also read Marine Electric Vehicles 2011-2021 and Energy Harvesting for Electric Vehicles 2011-2021 .
Image source: Kopf Solarschiff