A topic which is increasingly on the mind of the modern superyacht owner is that of fuel efficiency. Of course, for a new owner looking to commission a new-build yacht, this is something which can be factored into the choice of propulsion system used to power the boat, but what can be done for owners of existing boats who are keen to achieve maximum fuel efficiency and don’t wish to go through the expense of replacing their existing engines? Speaking to the experts from the Dutch naval architecture and design studio, Diana Yacht Design, we learn about the various tweaks and tricks out there for maximising fuel efficiency, thus making your yacht more attractive for resale, representing considerable cost savings, and, of course, helping to save the planet along the way.
1. Add a bulbous bow
Firstly, adding a bulbous bow to your vessel (a protruding bulb at the front of the boat just below the waterline) can save fuel for the rest of your boat’s life. This works by reducing the drag and wave-making resistance on your yacht, thus increasing its efficiency in the water and saving fuel as a consequence. If you do decide to go for this ‘nose job’ for your superyacht, bear in mind that bulbous bows come in a range of shapes and sizes and can be tailored to suit your yacht’s size and shape. In addition, if you extend the boat during a refit, that will also boost your vessel’s efficiency: a longer waterline creates speed, and so you will use less fuel travelling at the same speed.
2. Add a trim wedge
Another easy modification which you can undertake is to add a trim wedge at the stern of your yacht. The purpose of a trim wedge is to create vertical lift by directing the water flow downwards while the boat moves through the water at higher speeds rather than letting it sink at the stern. This enables the vessel to travel more effectively at top speeds, thus increasing the yacht’s fuel efficiency.
3. Harness battery technology
If your boat is going in for a refit, one excellent way to increase the fuel efficiency of your yacht is to install a battery pack. If you experience a power peak – a request for a lot of power in a very short time – you can use the energy stored in the batteries to fulfil that peak rather than using a generator, thus reducing the amount of fuel burned. This technique is called “peak-shaving” and is also increasingly used on commercial vessels which experience peaks and troughs in power usage, like tugs. Owners can also enjoy numerous other benefits from making the most of battery technology. Picture the scene: you arrive at a secluded bay in Greece, turn off the generator and can run off of your batteries for hours with your lights and air conditioning still working, undisturbed by the sound of a generator, thus creating a far more relaxing (and environmentally friendly) experience on board.
As Diana Yacht Design explains, “We already used this technology on the yacht Pamela V. We wanted to make this yacht as ‘green ‘ as possible and therefore the owner chose to install an energy storage inverter (ESI) on board.”
4. Change the hull colour
It may sound somewhat simple, but sometimes the best solutions are. Particularly with an older boat where the insulation might not be as effective as on a newer boat, repainting the hull colour from a dark colour to white can make a big difference as the white hull reflects the heat of the sun far more.
It is no surprise that houses in the Med or in the Caribbean are mostly white. White reflects the sun, so it becomes less hot than black. Why do you see more white cars in the Middle East than in the western part of Europe? For this same reason: because white reflects the heat. This same principle can also be applied to a yacht, as the hull of the yacht is a large area which can reflect the sunlight. So, if you feel like your boat could do with a bit of a make-over, you can give her a fresh new coat of paint and reduce your air conditioning load along the way!
5. Encourage guest awareness on board
One of the most effective solutions for increasing your fuel efficiency comes from a surprising place: the guests on board your yacht! Whether it’s running a bath for a relaxing soak or turning on the air conditioning to cool off during those summer evenings, everything that uses power on a superyacht is generated by burning fuel. With this in mind, gently encouraging guests to be aware of their onboard consumption could make all the difference, as this may not be something which they have previously thought about.
Finally, when discussing this topic, it would be remiss not to mention catalysers. Although it will not have a direct impact on the fuel efficiency of your superyacht, installing a catalyser between your engine and exhaust is a simple and effective way to make your yacht much less polluting. The SCR (Selective Catalytic Reduction) cleans up your exhaust fumes, thus enabling you to decrease your impact on the environment and is a solution which is recommended by Diana Yacht Design to all of their clients.
So, with this in mind, whether it’s guests closing the doors of an air-conditioned saloon, adding a bulbous bow to your yacht or giving your boat a hull paint refresh, there are so many solutions to help you to decrease the carbon footprint of your vessel – without having to make any major investments. This can vastly improve your experience onboard, represent considerable savings, and significantly reduce the impact of your yachting on the environment.