'You don’t see many of those around here, do you?' 'No, because it’s the only one in the world.' Just a couple of days ago we were at Ocean Terminal, admiring the unlikely-looking but entirely real vessel in front of us, and we were not alone. It attracted a great deal of interest from passers-by and tourists, as well it might. With a flat top entirely covered with solar panels, Tûranor PlanetSolar is the one and only entirely solar powered boat in the world, and took a break in Hong Kong on a record-establishing circumnavigation.
31m long and 15m on the beam, Tûranor PlanetSolar looks very much like one of those educational toys you might buy for a brainy nephew. And with good reason. This boat is a classic example of form-follows-function. A flat top to provide maximum area for the array of solar cells; carbon fibre construction to keep weight to a minimum without compromising strength; an 11-ton array of lithium ion batteries; ultra-slippery wave piercing catamaran hulls to allow the boat to move through the water with a minimum of resistance, and super-efficient electric motors driving half-submerged 2m propellers to push it all along. Captain Erwann Le Rouzic explains that it is the totality of the design that is revolutionary, not any one of the individual parts. 'Nobody has put all these elements together in one package before,' he says. 'All the parts – the solar cells, the wave-piercing hulls and so on – are well-established design technology. But putting them all together in a vessel capable of ‘sailing’ all the way around the world… that’s what is new.'
The Tûranor PlanetSolar expedition started with the vision of founder Raphael Domjan. 'I don't know why no one has tried it before,' he says. 'What we want to show is that all the technology that is in this boat is technology you can already find on the market, rather than just in the lab, and all of it can be applied to our normal, everyday lives.'
‘Tûranor’ is a name from Lord of the Rings, meaning ‘power of the sun’. The boat was built in Kiel, in Germany, and launched in March 2010. The world-girdling expedition set out from Monaco in September last year and has so far crossed the Atlantic and Pacific Oceans, and passed through the Panama Canal. For one fairly obvious reason – following the maximum amount of available sunshine – Tûranor’s route around the globe stays as close as possible to the Equator, between the Tropics, with the exception of a detour south to Australia. Passage planning for a solar powered vessel has to take into account the ocean currents, waves and winds, but with sunlight and the storage capacity of the world’s biggest lithium ion battery built into the equation as well. 'It’s a completely new programme of energy management,' agrees Le Rouzic. 'Our passage from Manila to Hong Kong was delayed a few days because of typhoon conditions in the South China Sea. Apart from safety considerations, we don’t have the power to drive through big seas and winds. But when we did start out, we found ourselves motoring in some of the very best solar sailing conditions we have experienced anywhere – the day before we arrived in Hong Kong our solar panels were generating just over 1 kW per sq m
537 sq m of solar panels are capable of generating 93.5 kW of electricity, enough to drive the two main 10hp motors that push Tûranor along at 4 kts – top speed is 8.5 kts, but that’s not energy-efficient – with some left over to charge batteries for operating in the hours of darkness and when the sun is obscured by clouds. Auxiliary 50hp motors assist with close-quarters manoeuvring. The ship can run for three days on fully-charged batteries, and a hot blue-sky Hong Kong summer’s day will fill them up again in two days. And remember, absolutely everything is running on that one power source – the navigation systems, the lighting, the on-board computers and the fans. There’s no air conditioning (that’s just too energy-hungry), but there is an excellent coffee machine!
It might cost very little to run – after all, sunshine is free, and nobody has succeeded in slapping a tax on it yet – but you can’t build a boat like Tûranor and run a global-sized project for nothing. Project financier Immo Stroeher has been pursuing the possibilities of solar power generation for a long time, but on land, in the 'stationary energy supply sector.' Stroeher believes that his US$18m investment in the Tûranor will 'help drive forward the development of sustainable energy technologies on the water and in other mobile applications. The aim is to offer future-proof solutions for sustainable living in major cities and environmentally responsible mobility concepts.'
Really, it is simply a case of setting a good example, and making the boat an ambassador for environmentally-friendly mobility. Tûranor’s first port of call after crossing the Atlantic last year was Cancun, Mexico, and a guest appearance at the UNFCCC (United Nations Framework Convention on Climate Change), 'providing visible proof of efficient and forward-looking use of solar technology to improve the climate of the planet.'
Arriving in Hong Kong and parking at Ocean Terminal has a certain poignancy for Le Rouzic - his last visit to Hong Kong was as Captain of a cruise liner and, yes, they were berthed in just the same place. By now, the silent solar ‘sailer’ has already headed off on the next stage of her journey, via Singapore to the Red Sea and back to the Mediterranean. It wasn’t a noisy departure – it’s not that sort of a project. Erwann and his crew of three enjoyed their Hong Kong visit, but were equally pleased at the prospect of being at sea again. 'I really enjoy stepping down from the main part of the boat on to the hulls. Maybe it is because I was a sailor before everything else – I love being close to the sea, and Tûranor lets you get very close to the sea. There’s no noise, and we are very often visited by dolphins and other sea life. In the Galapagos (where we were allowed into ‘marine reserve’ areas because we have no polluting engines) we had seals climbing out and basking on the hulls of the boat).
Tûranor PlanetSolar, with her silent electric motors, is quiet. Very quiet. Her history-making circumnavigation comes more under the banner of ‘quiet achievement’ than fanfares and hoopla. But it is very probable that this is a project that will be heard, loud and clear, all over our energy-hungry and frighteningly polluted planet.
Yesterday 23 August the Tûranor PlanetSolar departed Hong Kong en route for Vietnam and Singapore, in what was surely perfect weather for a solar-powered boat as well as for the photos! Anyone wishing to follow Tûranor PlanetSolar on the web can do so at: www.planetsolar.org TÛRANOR PlanetSolar
Designer: Craig Loomes, LOMOcean Design, Auckland, New Zealand
Builder: Knierim Yachtbau GmbH (Kiel), at HDW Howaldtswerke Deutsche Werft (Kiel)
Beam: 15m (solar panels ‘unfold’ to max beam 23m)
Solar array: 537 sq m. 18.8% efficient photovoltaic cells by SunPower Corp (San Jose, California), panels by SOLON AG (Berlin). Solar generator: 93.5 kW
Batteries: Lithium Ion, 338 v, 2910 Ah, 95%+ efficient. GAIA Akkumulatorenwerke GmbH (Nordhausen/Thuringa)
Electric Motors: 4 permanent magnet synchronous motors, total 120hp, 92% energy efficient. Drivetek AG (Ipsach/Biel, Switzerland).
Propellers: AIR Fertigung-Technologie GmbH & Co KG (Rostock, Mecklenburg-Vorpommern)