Hydro Motion
For 15 years our boats have been successfully sailing on the power of the sun. This means 15 years of sustainable innovation and inspiring the maritime sector for 15 years. In 2020 the team took the big next step towards a sustainable maritime industry by exploring uncharted waters and starting a new project; the Hydro Motion project. The team built world’s first flying hydrogen boat!
This year, we show our renewed identity as the TU Delft Hydro Motion Team and we will continue exploring the potential of hydrogen. We will design, build, test and race a hydrogen-powered boat. The goal is to inspire the entire maritime industry by showing what is possible with hydrogen. Together we can take the necessary steps towards sustainable shipping.
We, together with our whole team, are very excited about the project! If you feel the same, follow us on our social media channels to keep up with our progress during the year @hydromotionteam
Hydrogen
Why do we use hydrogen to achieve our goal? As scientists have been warning for years, the supply of oil and gas will inevitably run dry, and the exploitation of these energy sources will lead to irreversible climate change. We need to use different approaches if we want to move towards a zero-emission future.
There are several options to generate green electricity. These include wind and solar generated energy. To come full circle it is essential that we do not only look at the supply side of the chain, but also pay attention to the way we store this energy. Right now, the industry tends towards the usage of chemical cells when it comes to storing energy and powering electric transport. However, this is only part of the solution to reducing carbon emissions in the transport industry, because different applications require different solutions and the demand of lithium is growing faster than the supply can satisfy.
This is why we focus on an alternative way of storing green energy. The most prominent contender in our opinion is hydrogen. Using hydrogen as an energy carrier has the benefit that it doesn’t produce greenhouse gas emissions when used to generate electricity. On top of that hydrogen -when converted by fuel cells- has an energy storage density approximately 235 times larger compared to industry standard lithium ion battery cells. This is a huge advantage when it comes to powering a vessel.
When we show what our boat can do, we prove the viability of hydrogen. By working together with the maritime industry itself we can inspire change. We are all part of a problem, which means we can all be part of the solution. Only by working together we can sail to a sustainable future!
The first seaworthy monohull
This year was the first year we designed a hull for hydrogen. This led us to design a monohull, this means that the hull of the boat exists out of one piece. With this we also designed the first seaworthy monohull of the foundation. The two seaworthy boats before us used a trimaran. This monohull allows us to use all the space as efficiently as possible and be more manoeuvrable, which is important for our race.
On top of our boat we have two caps, but these are not just for show. If we have a hydrogen leak, the hydrogen will float upwards. Our two tanks are right below the caps, so the caps make sure the hydrogen has a place to leave the boat. This ensures more safety for our pilots in the boat.
Both the hull and the caps are made of carbon fibre, a light and strong material. To make sure our hull can withstand the rough conditions of the Mediterranean sea, we analysed exactly how many carbon layers we needed.
16 kg of hydrogen
The hydrogen we use to propel our boat is stored in the tank, located under our caps. Our hydrogen is stored in a gaseous state at 350 bar. To make this comprehensible, 350 bar is the pressure you would feel when two elephants would be standing on the palm of your hand. And even under this immense pressure, our tank is still 2,3 meters long and has a diameter of 50 centimetre. Now in our boat, we will be carrying 2 tanks of hydrogen, this is 16 kilograms which is double the amount of last year’s boat!
From the tank the hydrogen goes to the fuel cell. A fuel cell is a device that uses the chemical energy in hydrogen and transforms this into electricity. Our fuel cell uses hydrogen and oxygen to form water and generate electricity. We use this electricity to power the our boat.
The beating heart of our boat
The beating heart of our boat is our fuel cell, but to understand how our fuel cell actually works, we need to take a closer look at hydrogen itself. Hydrogen is an atom, an element. A hydrogen molecule consists of two atoms. You see two protons and two electrons.
Hydrogen goes from the tank to the fuel cell and passes through the proton exchange membrane. This is like a filter that only allows protons to pass through, but it blocks the electrons. That’s why, when a hydrogen molecule reaches the proton exchange membrane, it splits up into two protons and two electrons. The protons then pass through the filter to join an oxygen atom on the other side to form water. Because of the membrane the electrons have to travel through an external circuit, producing a direct current. However, we are not just letting it go through any ordinary external circuit, we are powering our boat with this!
A FLYING hydrogen-powered boat
Besides building a hydrogen-powered boat in just one year, we also make it fly! When a boat picks-up more speed, the drag with the water increases leading to more energy usage. By making our boat fly we avoid using those big amounts of energy, making our boat much more efficient. When sailing the foils create an upwards force, known as lift. When sailing faster, the foils create more lift. The foils and the struts lift the boat out of the water when we reach our take off speed of 25 km/h
The waves we face when we fly on the ocean influence the balance of our boat. That’s why we actively control our foils with a height control system. We have three sensors that constantly measure the height and orientation of our boat. That means that, when our starboard side drops ever so slightly, our sensors measure this and tell the starboard foil to adjust its angle of attack: generating more lift and re-balancing our boat. This way we can stably fly for extensive periods of time.
Propulsion
Just like many other boats we use a propellor to move forward. However with our struts and wings underneath the boat the mechanism connecting the propellor to our electro motor is quite complex. The propellor has to be at the end of the strut so it will always be submerged even when we are flying. The electro motor however cannot fit in this strut. This make the usage of a driveline necessary. The driveline translates the rotating of the electro motor down the strut into the propellor, making it spin. This is how we can keep moving forward even when we are flying.
