TBThursday 1975: The world’s 1st Solarboat

In October of 1973 when the western world was shocked by the price of gasoline (petrol) resulting from OPEC oil embargo, one of the first ways people adapted to their new reality was by dropping or cutting back on using fuel for recreational purposes. Like boating.

In his excellent book, Electric Boats and Ships: A History (buy on Amazon) author Kevin Desmond relates how this led Mr. Alan Freeman of Rugby England, to put together the world’s first solar powered boat, seen above.

For a little context, between October 1973 and February 1974 oil prices from supplying OPEC members rose 400% – from $US3 a barrel to $US12 a barrel (!!), and on the other side of the coin, the EnergySage website’s history of solar energy says that “by 1975…the cost for solar panels had dropped to just over $100 a watt. Today, a solar panel can cost as little as $0.50 a watt.” (!!!)

But we digress. Here’s how that boat came about so long ago.

From Electric Boats and Ships: A History:

“Predictions by Japanese, German and American researchers that within the next ten years the cost of solar cells would be reduced to 20p/w, with an increase in output to 10w/ft2, prompted Mr. Freeman, a 65-year-old former consultant on railway electrification switchgear, to make a practical study of the viability of future uses of this form of energy.

In 1967 Freeman had converted a Berkeley sports automobile to battery power and during the next ten years he had been silently totting up 16,000 km. After that, Freeman built a ¼-scale miniature car which he was able to power with a 14-watt Ferranti solar cell.

This vehicle model was then equipped with five Ferranti 7w solar modules mounted horizontally to produce 28 watts and give it a speed of 6.4 kph.”

With success like that under his belt, the intrepid engineer was ready to move on to boats!

“He put together the 2.5m / 8 ft catamaran – shown above – and equipped it with ten Lucas solar modules, each comprising 5 cells connected in series to give a maximum output of 1.3 w. The total weight of Solar Craft I worked out at 38 lb (17.2 kg), of which 7 lb (3.2 kg) were the solar panels.”

There is more detail in Electric Ships and Boats, but the upshot is that this aptly named ‘Solar Craft 1‘ was launched in the summer of 1975 and achieved a speed of 2.4 kilometres per hour: 1.5 mph, 1.3 knots.

Fast forward to today’s solar boats

Now there is an organization devoted to solar boat racing, Solar Sport One, which had more than 30 teams competing last year and is holding its first races of this season June 21-22 in the Netherlands.

The Monaco event featured in the video above is the premier solar boat racing event, started in 2014 as the Monaco Cup. This year’s July 2-6 races now include non-solar boats and has been renamed the Monaco Solar and Energy Boat Challenge to reflect this expansion and exploration of all zero-emission possibilities.

Below are three boats from the Solar Sport One circuit and Monaco event:

The Furia is from the CLAFIS Victron Solar Boat Team and holds the world solar boat speed record – twenty times the speed of Mr. Freeman’s invention – moving along on its proprietary hydrofoils at a zippy 49.3 kilometres per hour: 26.6 knots, 30.6 miles per hour.

A number of boats compete in the V20 class, which is a bit like the Formula 1 (or Formula E) of solar boat racing. Each of the teams must use this sleek hydrofoiling hull, designed by yacht designers VriPack, and make alterations to the propulsion system – within the confines of the weight and other regulations – to achieve the fastest speed and best results.

Another boat in this year’s race is from TU Delft (Technical University of Delft, Netherlands) The boat and team are perennial top competitors in the speed and slalom races and they are also going to cross the English Channel under solar propulsion later in the year using a new trimaran design.

We’ve come a long way since 1975!

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It’s a long way from that original catamaran, and as modest as the Solar Craft 1 seems now, it was a tremendous accomplishment for the time.

We all have tinkerers and dreamers like Mr. Freeman to thank for exploring possibilities, taking chances and opening the world to zero emission and silent boating. It’s always amazing how these dreamers respond to challenges changes like the oil embargo of 1975.

There are challenges ahead as we address the amount of carbon in our atmosphere and oceans, and if you take a couple of minutes to scan through other articles on Plugboats, or through Electric Boats and Ships: A History, you’ll find there are no shortage of dreamers and visionaries working on solutions.

Click »» here to read some of the other Throwback Thursdays of electric boat history.


Electric Boats and Ships: A History
Available from Amazon, including Kindle

Amazon Customer Review: “Desmond’s new book leaves no doubt that electrically powered vehicles are already a fixture on the firmament of propulsion and will continue to be so for the foreseeable future. Well illustrated, meticulously written and researched, this book is a guaranteed ‘must’ on the bookshelves of all who have interest in this subject.


DISCLOSURE: The excerpts from Electric Boats and Ships: A History have been provided by Mr. Desmond and the book’s publishers at the request of Plugboats. Plugboats receives a standard Amazon affiliate commission for any copies purchased through the links on this site.

Images used in the photo montage are ©CBS, AP, The Daily Mirror, The Washington Post, Volkswagen, Universal Pictures, Monty Python and are used in a fair use manner to collectively evoke and symbolize the news events of 1975.
Alan Freeman image: Collection of Kevin Desmond
Furia, V20 Foiling Solar Boat: ©Y.C.M.
TUDelft: TU Delft SolarSport Team

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a luxury 64' yacht seen from above with solar panels on its roof

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