Leave Only Ripples

By Matt Lis

“Leave only footprints. Take only memories” they say of walking in the countryside, for those of us who enjoy hours afloat I suppose that translates to “Leave only ripples” so how do we achieve that?

When Julia asked me to write an article on how boaters can reduce their impact on the Deben I wonder whether she appreciated the enormity of the topic. I will fail to answer all questions for all people but by focusing on just a few topics I can try to summarise those things in just one long article.

‘Evoelectric’ afloat

If we are looking to enjoy boating with minimal impact on the people, the other creatures, and the environment itself then let’s start with the obvious, leaving only ripples…and not wake.

If your vessel is being propelled by anything other than wind, tide, paddle or oar then one of the easiest ways to make a difference is simply to slow down. Unless you have the latest in hydrofoiling technology, going faster will mean using more energy and more fuel. Wash from boats is a problem too; it causes river bank erosion and upsets other boaters and wildlife. A third of Suffolk’s saltmarsh is on the River Deben and that saltmarsh is one of the most effective habitats for locking away carbon. Saltmarsh is very difficult to naturally make (although manmade efforts using dredged material can be very effective in helping) but it is very easy to damage. Wave action, both natural and that from boats’ wash, erodes the marsh and undermines the plant growth above. So there we are, problems solved! But what if you want to go further still?

There are many things that can be done to reduce one’s impact on surrounding environs when boating. I have been asked here to focus on but a few; specifically, zero-emission propulsion, biocide-free antifouls and the disposal of boats and their constituent parts. It will be known to many who live locally and/or read The Deben that we at Woodbridge and Waldringfield Boatyards are working on projects relating to all of these topics so I will try to be informative and as impartial as possible.

First things first, zero-emission propulsion. This is one of the biggest growth industries across all forms of transport and whilst the marine industry always lags behind, progress is very much coming. The conversations that are being had in the marine sector are echoes of those that you will have already heard in the news relating to cars, trucks, buses, trains and bicycles; how can internal combustion engines (ICEs) be made cleaner? Is electric propulsion the answer? Which form of electric propulsion is the answer? How does the industry make the transition? Can infrastructure be made to cope if we do make the change? And so on and so on. With boats as with wheeled transport, the answer is not simple.

It is a lesser known fact that prior to running Woodbridge Boatyard I had four years away from the marine industry and instead threw myself into the world of electric and hybrid trucks and buses. Between 2015 and 2019 I was part of a small startup and surrounded by brilliant individuals whose considerable minds and creativity were bent primarily upon the task of electrifying buses and subsequently making our cities a cleaner, more pleasant place to be. Before that I worked for one of the world’s largest engine manufacturers so, whilst my references will be a little out of date, I will have a stab at those questions.

How can internal combustion engines (ICEs) be made cleaner? The marine industry as with all others has its national and international governances and all new engines have to meet certain emissions standards. These standards are considerably more stringent for larger engines than they are for the small ones. Boats using large engines are now installing selective catalytic reduction (SCR) technology when they are built to remove nitrogen oxides (NOx) and sulphur oxides (SOx) from their exhausts, but this technology is expensive, requires a lot of heat to work and is a big bulky addition to an exhaust in an already cramped space so the technology is not being scaled down for small engines. That being said, engine manufacturers are constantly making improvements to their technology and whether it is through changing piston shapes or reducing weight, improvements continue to be made.

‘Evoelectric’ at Southampton Boat Show

Is electric propulsion the answer? For most of us reading this article, yes, it probably is. Electric propulsion has been proven in just about every kind of boat you could care to mention, from canoes to big tugs, and it works. Can it do everything as well as diesel can, no, but does it need to? You may have seen the electric launch that we, Woodbridge Boatyard, took to Southampton Boat Show recently, pottering up and down the river. People keep telling me that it won’t work for them because electric range is limited and they keep their boat on a mooring but from fully charged ‘Evoelectric’ can do 60Nm at 4.5 knots with 20% left in the ‘tank’. That means that you could be launched fully charged, go from Woodbridge to Waldringfield and back half a dozen times without worrying, treat yourself to a night in the marina to recharge and then you will be ready for another half dozen trips to The Maybush. It is not the solution for all but for many I think that is ample and with the amount of investment and development currently on going the world over the technology is only going to get better and more affordable.

Which form of electric propulsion is the answer? Let’s break it down to energy storage and propulsor. The principle approach at the moment is to use batteries to store energy but work is being done on hydrogen and other options. Hydrogen is brilliant stuff but only truly an effective option if you have a source of ‘green hydrogen’ available which is few and far between in the UK. ‘Green hydrogen’ is typically considered to be hydrogen made either as a waste product of another industry or hydrogen made by splitting the constituent particles of water using ‘excess’ renewable energy. Splitting water to make hydrogen is incredibly energy intensive and wasteful but if you are, for instance, the city of Cologne with a huge chemical industry and waste hydrogen or the Shetland Isles with more renewable energy than you can use then it is a fantastic option.

For the rest of us chemical batteries remain the first choice. There are myriad chemistries competing for the top spot and many socio-economic and environmental problems relating to the mining of relatively scarce materials and I am afraid that neither is an area of my expertise save to say that I recommend going away and doing further reading on both because they are as interesting as they are complicated. For a moment let’s simply summarise the chemistry question as lead vs lithium (a horrible oversimplification). Lead is relatively common, safe and inexpensive but lead-based batteries are heavy and bulky. Lithium batteries, like those on our ‘Evoelectric’, are more exotic. They are more energy dense and therefore lighter and more compact but that does come at a financial price and the ethics of mining lithium are generally not very good although I must stress that we have sought what assurances are possible that the lithium and other metals used in the batteries we offer are ethically mined. Which chemistry is right is a question of application; if weight and space is not an issue, a canal or workboat for instance, then lead is probably the route to choose, but if space is at a premium and weight needs to be kept down then lithium may be the route to choose. And then there’s safety. Lithium can burn underwater without the presence of oxygen due to the self-propagating nature of the chain reaction that happens during a thermal runaway reaction. The trick, silly as it may sound, is to avoid getting into a thermal runaway situation. In a good quality battery clever monitoring and software is used to stop that situation from ever being allowed to happen by breaking the chain before it can get out of control. For this reason, the batteries that we use are the very best and, whilst it means they are not cheap, they are the only batteries on the market that I am aware of that carry the Det Norske Veritas classification society seal of approval and DNV don’t give that out lightly.

So now the easier part of the question, the propulsor. These days electric propulsion comes in all shapes and most sizes. From 0.5hp outboards for kayaks to multi-hundred kilowatt electric motors for planning speedboats via slow shaft-driving motors for narrowboats, 360° rotational or fixed pods and systems specially designed for foiling. Most relevant to this conversation though is the fact that smaller shaft, pod and outboard options are becoming easier to find and more competitively priced.

Most of the boats in our own yard with inboards carry a single or twin cylinder diesel of 10hp – 30hp and, whilst a lot of the early excitement in the industry was for fast and flashy, this large segment of the market is now being addressed. Options are now coming to market from recognised marine names such as Fischer Panda and Vetus as well as relative newcomers like ePropulsion and smaller brands such as the Deben’s own Lightningcraft (now based at Waldringfield Boatyard). Several boats that you see on the river are now running these types of system; Robertson’s Boatyard’s lifeboat-derived trip boat, the ‘Sarah Ann Austin’, as well as Josh’s own ‘Switch’ are powered by Lightningcraft systems, the beautiful classic yacht ‘Mist’ has a Torqeedo system, the clinker launch ‘Rivermaster’ was converted to electric by Waldringfield Boatyard last winter and the Woodbridge Boatyard assembled DebenDrive package demonstrated in ‘Evoelectric’ uses a 10kW Vetus motor at its heart. Some systems are designed specifically to target the home installation market so, for those suitably competent, you don’t even necessarily need the services and expense of professional installation.

Can infrastructure cope if we do make the change?

With the majority of boats on the river using swinging moorings it will be more difficult here than in other places but, if the demand is there then ways will be found. As well as shoreside charging options at several places along the river there is the possibility of being self-sufficient by integrating onboard charging using solar, wind or tidal generation. Whilst not yet common, floating boathouses with integrated solar arrays are also being experimented with for boats without masts or keels. We do in fact have one of these on our own drawing board but we haven’t got around to turning it into a reality just yet.

There are of course other methods of emission-free propulsion but I am not sure that I need to make this article any longer by explaining sails, paddles or oars to anybody…

Shetland‘ one of several boats testing Seajet Eko on the river

Moving on from propulsion, antifouling is another area of boat ownership which may not sit entirely comfortably with all. In short, there are many, many types of antifouling on the market and over the years various types have been outlawed because their environmental effects have been judged to be too great. In some places, local bylaws go beyond national and international levels to further regulate their use. Antifouling plays a very useful role in keeping the wet part of a boat clean and free of marine growth and therefore it helps to keep hulls slippery and efficient and reduces fuel usage but at a price. Some antifouls rely upon having high copper contents which acts as a natural biocide and deters plant and animal growth, others rely upon being too slippery for the growth to attach too and a third kind erodes and when something grabs hold the paint falls away taking the wannabee passenger with it. Other technologies exist such as acoustic systems. Some swear by these, others think them a gimmick; I haven’t tried them so will reserve judgment but it would be interesting to hear from anybody who knows more.

The two types of biocide-free antifouling that Woodbridge Boatyard is currently involved in testing are both from a Dutch paint specialist called Seajet. We have no formal relationship or particular allegiance to Seajet but are happy to be helping them to be testing biocide-free antifoul. Currently a handful of our customers (including RDA Vice-Chair Colin Nicholson) are using Seajet’s 021 Eko product which falls into the eroding variety of paints and we are recording the marine growth seen year to year on these boats as a point of comparison for Seajet who continue to tweak the formula. The other type is Seajet’s Bioclean Eco, a silicone-based system which is too slippery for fouling to attach firmly to. We are testing the silicone system as part of a test panel along with the eroding product and a couple of Seajet’s ‘traditional’ antifouls as part of a more scientific test. If and when the Eko product performs as well as the traditional antifouls that we currently use as standard on our customers’ boats we will be making this our default product but for the time being it is being used by request although we hope that the number of requests will grow. When considering options, it is worth consulting with your local boatyards to find out which paints they find to be most effective. This advice will vary from river to river and even within the rivers as the depth, flow rates, temperature, boat usage and position will affect what is likely to grow. It is also essential to check with your boatyard whether they will accept boats painted with silicone antifouling. Following several documented incidents of boats slipping in the slings during lifting, many yards and marinas will not lift boats with silicone antifouling as a precaution. At the current time, our own yards are amongst those being cautious.

As well as using biocide-free Seajet Eko antifouling, Deben Cherub ‘Jubilee’ has her topsides painted with organic linseed oil based paint rather than a normal petrol-chemical derived paint

As test data is gathered from our collaboration with Seajet, we will happily share more information about how their biocide-free antifouls are performing.

As with the propulsion, cleaner still may be to use none. ‘Dry sailing’, the practice of only getting a boat wet when it is being used takes away almost all risk of fouling. For some this is launching and recovering from a trailer each time, for others it may be requesting that a yard lift the boat in and out but a growing number of options are also available for drive-on docks and for some this may be an attractive solution.

Lastly, but far from least, is the problem of disposing of watercraft and their constituent parts. This is a huge, and I really mean huge, problem for the whole industry. With the advent of fibre-reinforced composites and the subsequent boom of fibreglass (GRP) boats there are now a colossal number of nearly indestructible boats in the world. I have heard obscene numbers banded about, 50,000 boats a year needing to be disposed of, unfathomable volumes. So, rather than getting bogged down in trying to solve the whole world’s problem, let’s come local again. One Sails at Suffolk Yacht Harbour have joined the ReSail project and will happily take in your old sails for upcycling and recycling. If you are unable to get your sails to Levington then we are happy to accept them at Woodbridge Boatyard and then we take them to One Sails the next time we are heading over to Levington. The Royal Hospital School are also involved in a sail recycling project but, at present, that is only suitable for very specific sails. It is worth noting too that One Sails are also making and marketing fully recyclable sails and sails with integrated solar panels too!

Pallet full of sails for recycling at ‘One Sails’

A small number of businesses such as BoatBreakers will, for a fee, take end of life boats away and, if they cannot rehome them, strip them of useful or recyclable parts before disposing of the GRP in a legal and controlled way. At present, as far as I know, there is no way of truly recycling GRP so it is generally ground up to a powder and integrated into new products as a filler or mixed into concrete as a reinforcing material which does have the merit of avoiding the need for virgin material for the same purpose. Before a boat is disposed of though, serious thought should be given to whether it really is at the end of its life. The greenest boat is after all the one that already exists. Whilst acknowledging my obvious bias, refurbishing and breathing new life into an existing hull can be a cost-effective and rewarding way of ‘building’ your next boat, has the added benefit of keeping a hull out of landfill and you will probably be spending your money with a local business rather than buying a new boat from the other side of the world. By way of example, I point again to our dear ‘Evoelectric’, this time last year we extracted her from a hedge and started the project by repairing a hole in her bottom and now she is a handsome ‘new’ boat.

There are myriad other things that can be done to reduce one’s impact, things as simple as changing to environmentally-friendly cleaning products or slightly bigger steps such as switching to a 4-stroke outboard from 2-stroke if going all the way to electric is unsuitable. There are, I’m pleased to say, so many available improvements that I cannot list them all here so instead I advise doing further research and chatting to your boatyards and chandlers for advice.

In summary, a great deal of work is being done by people who specialise in every aspect of what makes a boat and, through making relatively small changes, a large cumulative result can be achieved. I have only scratched the surface of a small number of topics here but hopefully some of you will have had your interest piqued enough to carry on your research and implement some changes.

Matt Lis

Myself and Eric racing ‘Jubilee’ at the weekend with ‘La Mouette’ in the background. Courtesy Charmian Berry

Matt Lis is General Manager of Woodbridge and Waldringfield Boatyards. He grew up in Burnham-on-Crouch, Essex, studied Marine Engineering, and worked for a marine engine manufacturer and an electric vehicle start-up before moving to Woodbridge in 2019.

Woodbridge Boatyard was founded in 1889 as Everson’s and continues to be a strong local boatyard with a particular focus on wooden boat repairs.

Waldringfield Boatyard was founded in 1921 by the Nunn Brothers, former apprentices of Everson’s. In May 2023, Waldringfield Boatyard was brought into the same ownership as Woodbridge Boatyard allowing for strengthened collaboration between the two yards whilst both maintains its own intertwined identity.