March 16th 2021: A growing number of ship owners and shipping companies are shifting their focus to electric sailing. Their main goal? Future-proof vessels with considerable fuel savings, reduced CO2 emissions and less noise pollution. But do these benefits always apply? Piet Brouwer Electrotechnology shares its vision on electric sailing, and explains why it may not necessarily be the most sustainable option.
To refresh our memory, electric sailing can be realised in two ways in 2021: either the propulsion is fully electric, powered by batteries and generators, or the vessel is hybrid, in which case it can switch between electrical and mechanical propulsion. Both types are increasingly popular, especially as owners and shipping companies look to invest in a vessel that is ready for the future.
The question as to whether electric sailing is always the best and most sustainable option is more complex than it might at first seem, says Piet Roskam, sales manager at Piet Brouwer Electrotechnology. “Whether or not to opt for electric sailing depends on a vessel’s sailing profile. Electric sailing is an interesting option with a very variable profile but that does not make it by definition the most sustainable choice. First you need to consider the concrete benefits for your type of vessel and its use. We are currently working on four projects with electric or hybrid propulsion, for example, each of which has been designed in a completely different way.”
Many vessels are now being equipped with hybrid propulsion, giving owners or shipping companies the benefits of electric sailing at low power and diesel-direct propulsion at high power. Roskam: “Take offshore working vessels, fishing boats or luxury superyachts, for example, which are often run stationary with traditional main engines. At such times very little of the energy capacity is being used for propulsion, which is extremely inefficient. You could also consider short-sea vessels. Departing from Hamburg, then a leg on a river, out to sea, a fjord, back into port – they often sail at reduced power. Hybrid solutions with smaller (diesel) generators are a smart choice in these cases. They are extremely efficient for stationary use, stand-by operations, manoeuvring in ports and sailing shorter distances.”
Piet Roskam also sees the practical benefits of hybrid sailing: “It often requires less mechanical maintenance as the engines run fewer hours. In addition, sound levels are lower and vibrations minimal. For instance, PBE recently worked on a 32-metre carbon Vitters sailing yacht, equipping her with peak shaving and night mode facilities. In hindsight, night mode had many more benefits than just the quiet. These included swimming without exhaust fumes and enjoying a nice cup of tea without noise pollution. It also considerably reduced the vessel’s operational hours.”
In practice, Piet Brouwer Electrotechnology has already designed and installed various (new) electric solutions. “We’ve used both AC and DC, depending on the sailing profile. Our team includes a student from Delft Technical University who focuses on DC systems.” According to Roskam, the EMC regulations are especially important when building an electric vessel. “Cables can cause disruptions, leading to issues such as engine overloads or flickering lights. Electric supply pollution is another aspect that should not be underestimated. You really have to know what you’re doing or you can cause significant problems on board.”
And finally, the most important question: would Piet Brouwer Electrotechnology recommend electric sailing? “That really depends on the client. Every vessel has a unique sailing profile and a unique purpose which demands a custom approach. We are happy to discuss with the client whether electric sailing is a feasible option for them, and always work with the best yards, suppliers and universities to come up with an optimal solution.”