The Electric Boat Association's fleet includes a growing number of solar boats. Some are run as passenger boats by business members, others are privately owned. The boats are extremely diverse, ranging from small lightweight craft designed to take just one or two crew up to passenger boats capable of carrying 50 or more people, and a private 68ft canal barge which is presently the largest electric boat on the UK's inland waterways. What all these craft have in common is their use of onboard solar photovoltaic (PV) modules to charge propulsion batteries, producing a very environmentally benign method of transport.
The solar fleet includes Collinda, a 22ft (6.7m) catamaran owned by EBA past president Malcolm Moss, in which he made the first-ever solar-powered crossing of the English Channel in 1997; a solar canoe owned by Cedric Lynch which has featured in the Guinness Book of Records and holds the record speed for a solar-powered boat; and the 21ft (6.4m) catamaran Solar Flair in which Paul and Ulrike Lynn made the first-ever solar-powered cruise along the entire non-tidal Thames in 2003 (124 miles, 43 locks).
Click here for photos of the EBA's entire solar fleet
The term "solar-powered" should be used with caution. The extent to which a particular boat can run on solar energy depends on its technical design, the amount of photovoltaic cells carried, the solar climate where it is based, and its pattern of use. A private boat, used infrequently and mainly at weekends, may very well get all its propulsion energy from the sun; but a commercial passenger boat offering scheduled daily trips is unlikely to do so and would normally be better described as "solar-assisted". Such issues have recently been discussed in a Technical Report in Electric Boat News entitled "What is a Solar Boat?" which also introduced a new performance measure known as the Solar Boat Index (SBI). click here to download this article (requires Adobe Reader)
Solar Passenger Trip Boats
The following operators offer trips on solar passenger boats. We recommend you visit the relevant website and/or telephone before your intended trip to confirm sailing schedules and availability.
Loch Lomond & The Trossachs National Park Authority
Boat: Bata Greine 43 ft catamaran
Takes up to 12 people from the Duncan Mills Memorial Slipway, Balloch, Loch Lomond.
phone: 01389 722030
Serpentine Hyde Park, London
Boat: Solarshuttle 48ft (14.4m) catamaran
Takes up to 42 passengers on trip across the serpentine. Departs at 30 min intervals (adults £3)
phone: 0207 262 1330
Chichester Harbour Conservancy (West Sussex)
New Era Boat Trips
Norfolk Broads Authority
Boat: 29ft (8.8m) catamaran Ra takes up to 12 people including wheelchair users from Gay's Staithe on a 1¼ hour trip round the recently restored Barton Broad
phone: 01603 782281
For technical details of the boats - click here (requires Adobe Reader)
The EBA publish an Information Sheet on "Solar Photovoltaics" which gives a full account of PV and its use in solar boats.
A copy may be requested from the EBA Secretary (free to members).
Solar Powered Boats
An article by Andreas Kindlimann of Grove Boats, Yvonand, Switzerland
While experiments with electric powered craft began in the 1830s (and included the work of such pioneers as Englishman Sir William Grove who was the first to introduce fuel cells as a source of energy on board a boat) it wasn't until the 1890s that electric boats became popular, especially in England where the clean and silent electric craft were often preferred to smoky steam driven boats. In the late 1890s electric charging stations along the River Thames were commonplace. The success story of the diesel and petrol engine brought an abrupt end to the development of electric boats, and it wasn't until people became more aware of environmental issues and solar cells became readily available that the second birth of electric boat production began. The first documented solar powered boat was Solar Craft 1 built by Alan T. Freeman which made its maiden voyage on 19th February 1975 (see Electric Boat News Volume 21, number 2, 2008).
It was clear from the beginning that along with the problems relating to energy storage, the resistance of the hulls would have to be reduced to a minimum. That is why the first solar craft consisted of simple photovoltaic panels set up on canoe-like hulls. These boats were often highly efficient, but also vulnerable and not very seaworthy. The initiatives came either from enthusiastic environmental activists or universities and technical high schools. At that time virtually no commercially orientated boat manufacturer thought that there was a market for solar powered craft, due to the lack of acceptance of solar powered boats by the general public.
In the 1990s, some pioneers developed the technology further, enabling the first boats to enter commercial service, mainly around inland waterways - see the Solifleur in use on Lake Neuchatel as early as 1994. Built by the Swiss company MW-Line, it was financed by the nature friendly Yves Rocher cosmetics company and still runs today through a nature reserve.
Sun21 on her 7,000 mile journey from Basel
in Switzerland to New York May 2007 more details
That decade saw quite a number of solar boat races organised throughout Europe and the USA, popularising the concept and further developing the techniques. The Frisian Solar Challenge remains a widely sought after competition (unofficially called the World Cup for Solar Powered Boats), bringing together engineering schools, passionate boat builders and even some technology companies.
Improved battery storage and performance of the photovoltaic panels opened the way to "world premiéres': the Channel was first crossed in 1997 by SB Collinda, the Pacific in 1996 by Malt's Mermaid and for us Europeans probably the most significant, the first Atlantic Crossing by Sun21 which left Basel to reach New York in 2007.
These developments proved that solar powered boats can do very well; the downside of their relative lower speed being very much offset by their advantages of silent navigation, zero emissions, little wavemaking and last but not least low operating costs.
Recent developments in the fields of solar powered water craft
Two main factors encouraged the current growth of solar powered boats: technology and popularity, setting up the foundations for an emerging commercial market.
a) Technological improvements:
- Energy storage: helped by recent developments notably in portable electronics (laptops, phones) and then industrialised in the massive quantities demanded by the automotive world, new types of batteries appeared alongside the well known and proven lead-acid batteries: Nickel-Cadmium, Lithium-Polymers etc. While some of these new products still face some issues (high costs, security, lack of recyclable circuits) they very clearly opened the door for extended range, lower weight and faster recharging time as well as longer life-cycles.
- Improved performances of the photovoltaic panels: improvement in both production techniques and the implementation of solar-tracking mechanisms resulted in a drastically increased efficiency of the newer generation of PV panels (cell performances of 22%, enabling an overall 18% performance per panel, are now largely the norm). In addition, mass-production (solar powered boats used industrial standards, i.e. identical to the ones that one can install on a roof or a PV-Solar farm) enabled a steep price decrease.
- Hybrid systems: after the natural move to enable the batteries to be recharged from the grid as for any pure electric boat, new sources of energy appeared as a complement to the solar power: diesel operated in-board generators or even fuel-cell (see the Hamburg WHY super yacht). On top of the improved batteries, these systems function as range-extenders, sometimes necessary to overcome the relatively limited range. These hybrid systems start to blur the difference between a 'pure solar' and a "pure electric" boat.
Quite a few factors explain a shift toward a better understanding and a stronger interest in solar powered boats.
- The automotive industry's move towards electric vehicles certainly explains a massive shift towards a better understanding and confidence in electric propulsion.
- In the same way, the ever increasing surfaces covered with photovoltaic panels popularised solar energy as a trusted source of power.
- The increased oil price and global geopolitical context in oil producing countries as well as the recent Fukushima catastrophe definitively encourage a move towards a "green and clean" attitude benefiting, solar-powered boats.
- Also important, the legislative framework evolved in some areas encouraging the use of less polluting water craft and thus indirectly encouraging solar-powered boats: partial or total prohibition of combustion engines (see for example some Austrian Alpine lakes), the move away from 4-stroke motors as well as limited speed or engine-power (Swiss lakes for example) or even reserving some harbour slots for electric motors only (Lake Annecy in France is currently introducing such a scheme).
- Lastly, a significant number of boat users now demand a more relaxing, quieter and cleaner approach to navigation. Solar powered boats, with their pollution free zero emissions, quiet and clean propulsion fulfil these aspirations.
The above factors explain the increased demand for solar-powered craft, a commercial market is thus slowly developing along the following lines:
- Boats for private users: the French company produces the sea-going Aequus family dayboat.
- Professional transport, focus on tourism: the Swiss based Grove Boats continues the pioneering work of MW-Line and further develops the famous "Aquabus" (12-100 passengers)
- Professional transport, focus on collective transport: the German based Kopf-solar competes with the French Alt-En
- Experimental projects: quite a few newcomers, among them the Australian based Solar Sailor
Solarwave is the first completly self sufficient ocean-going electric yacht. The energy is being produced by solar panels. In addition to the electric motor this source supplies also the electronics, electrics as well as the household appliances and even the water-maker for the production of drinking water from seawater. No fossil fuel is used on board, no gas for cooking, no diesel for the propulsion, no fuel cell. It is only solar-energy that is transferred into electrical energy. No fumes, no pollution, no costs. When the Solarwave Catamaran stops in a harbour, only food will be taken on board, no fossil fuel, not even water. further details
Turanor PlanetSolar "Super yacht"
PlanetSolar is the largest solar boat in the world, it operates solely on solar energy captured by its 512m2 of solar panels and has circumnavigated the globe exclusively on solar power.
It took several months of research to finalise the vessel's design whose primary purpose was to cross the planet from east to west. The engineers had to optimise the collection and storage of the energy, as well as the boat's aerodynamics, its propulsion and choice of materials.
The carbon structure of this power-driven futuristic vessel is lightweight and durable. The 512m2 of photovoltaic panels supply 6 blocks of lithium-ion batteries, to date the largest mobile civilian battery in the world. This technology provides maximum power and energy density for a new type of autonomous navigation. more details
Links to Solar Related Websites
Solarwave Catamaran: www.solarwave.at - First self sufficient ocean-going electric yacht
Sun21 Catamaran: www.transatlantic21.org - First crossing of the Atlantic under solar power
Solar Navigator Project: www.solarnavigator.net - World's first solar boat circumnavigation attempt
PlanetSolar Project: www.planetsolar.org - Around the World in 80 Days by renewable energies
Bat Sol: www.la-maison-du-soleil-17.com/batsol - French Solar boat project