Energy Observer, the first energy self-sufficient boat powered solely by renewable energies and hydrogen was officially named in Paris on 6 July after sailing from Saint-Malo to the mouth of the Seine, then up the Seine to the French capital.
The boat was built in Canada in 1983 as a maxi-catamaran (length: 30.5m, beam:12.8m). In 1994, as the Enza New Zealand, she won the Jules Verne Trophy with Peter Blake at the helm.
(© : Jeremy Bidon / Energy Observer)
Energy Observer spent the last two years in Saint-Malo undergoing a radical conversion, including the incorporation of an array of innovative technologies. The work was performed by a team of sailors, naval architects and engineers under the watchful eye of skipper Victorien Erussard and expedition leader Jérôme Delafosse.
The team set out to make the boat 100% energy self-sufficient. “There’s no miracle solution to combat climate change, only partial solutions that we must learn to use in combination. That’s what we’re doing with Energy Observer. By applying our energy and that of society at large to know-how made available by our sponsors and a host of other companies, laboratories, startups and organisations, we aim to harness a combination of natural energy sources” says Victorien Erussard.
Energy Observer skipper Victorien Erussard and expedition leader Jérôme Delafosse (© : Jeremy Bidon / Energy Observer)
CEA-Liten (Laboratory for Innovation in New Energy Technologies and Nanomaterials), a division of the French Alternative Energies and Atomic Energy Commission, or CEA, is playing a key role as the lead developer of the boat’s energy architecture.
The first challenge is to combine multiple energy sources and tailor them for use in a marine environment while bearing in mind the boat’s size, weight and strength constraints. The second is the fact that the energy sources are all intermittent as the output of the solar arrays and wind turbines varies according to the amount of sunlight and wind. It takes some juggling and energy storage technologies to supply the boat with 24/7 power irrespective of the weather conditions and without using fossil fuels.
Energy Observer en route (©: Romain Frogé - Energy Observer)
To this end, Energy Observer is based on a multi-source concept combining solar panels, wind turbines, a traction kite, reversible electric propulsion motors, batteries, a fuel cell and high-pressure tanks to store hydrogen. The entire energy system is managed by a smart power distribution and storage system developed by CEA-Liten. Real-time performance monitoring enables local and remote operators to continuously optimise the power flows.
Energy generated by the solar arrays and wind turbines powers a 24V network for the boat’s control, command and safety systems and a 400V network for propulsion and hydrogen production by electrolysis. When necessary, hydrogen is fed from the high-pressure storage tanks to the fuel cell to generate electricity. The kite is controlled by a dedicated computer system to increase the boat’s speed and reduce power consumption. The kite is also used to produce energy. But how? When the wind conditions are right, the propellers drive the propulsion motors (2x41kW at 3000rpm) in reverse as hydrogenerators. Output in generator mode is 2x2.5kW.
With traction kite aloft (©: Kadeg Boucher - Energy Observer)
Three types of solar panels, including a non-skid type (©: Jeremy Bidon - Energy Observer)
Energy Observer is clad with 130sq.m of high-performance solar cells generating 21kW. Three different types of cells are used. One type is curved and the second two-sided while the third features a non-slip finish. “French solar energy research body INES shaped conformable cells to fit the boat’s structures while the arrays on the aft wings carry two-sided heterojunction cells that convert direct sunlight as well as light reflected by the hull and the sea. The cells fitted to crew work areas feature a non-slip surface. The operating voltage, wiring and connectors are all specially designed for optimal crew safety,” says Florence Lambert, CEO of CEA-Liten.
The solar arrays are linked to two vertical-axis wind turbines, each rated at 1kW and specially designed for use on a moving platform.
From behind. Note aft wings with two-sided solar cells (©: Jeremy Bidon - Energy Observer)
Aft wing with two-sided solar panels (©: Jeremy Bidon - Energy Observer)
The solar arrays are linked to two vertical-axis wind turbines (©: Jeremy Bidon - Energy Observer)
To meet short-term demand, electricity generated by the solar arrays and wind turbines is stored in lithium-ion batteries, an ideal power source for propulsion motors. The Flex EP7 battery modules were developed by Forsee Power.
To further increase the boat’s self-sufficiency, Energy Observer is equipped with an electrolyser to convert desalinated and de-ionised seawater into gaseous hydrogen for the fuel cell. The gaseous hydrogen is compressed and stored in eight high-pressure tanks holding 322 litres or 62kg. When required, hydrogen is fed to the fuel cell which produces heat and electricity by chemically combining hydrogen and oxygen. The heat is used to warm water for onboard circuits.
Testing the batteries in a safety enclosure (©: CEA-Liten)
Testing the energy control system (©: CEA-Liten)
When the solar panels and wind turbines fail to produce enough power for onboard needs, the fuel cell takes over. The different technologies, including the kite and the propulsion system in generator mode, work together to provide 24/7 power.
This combination of technologies and their control systems represents quite a feat. “We’re working towards a true energy revolution. This boat will boost the technologies proper, further research and the transition to industrial applications. It is a living, sea-going laboratory designed to test a suite of CEA-Liten technologies in a difficult natural environment, to contribute to solutions to the challenges posed by climate change, and, in time, to give rise to green jobs,” says Florence Lambert, CEO of CEA-Liten and Energy Observer sponsor.
Florence Lambert, CEO of CEA-Liten and Energy Observer sponsor (©: Jeremy Bidon - Energy Observer)
Energy Observer will test new technologies, particularly the use of hydrogen which can be produced anywhere. The aim is to accelerate the development of these technologies whether at sea, in ports, on islands, or elsewhere. “The objective is to achieve energy self-sufficiency. We also hope to promote the transition to renewable energies and their use by corporations, local and national government bodies, and citizens everywhere by demonstrating that the road to a cleaner future is paved with innovations, including energy architectures developed by CEA-Liten,” says Victorien Erussard.
On 26 June, Energy Observer set off from Saint-Malo on a six-year, round-the-world, zero-fossil fuel trip including 100 stopovers in 50 countries, beginning with Paris. In addition to promoting the project in its own right, the organisers aim to “contribute to a cleaner future that is more respectful of both mankind and the environment”.
Original by Vincent Groizeleau, translated and adapted by Steve Dyson
Energy Observer arriving in Paris on 4 July (©: Jeremy Bidon - Energy Observer)