RECENT events in the automotive world related to tightening emissions regulations and the emergence of new electric-only brands such as Tesla has hastened the uptake of electric vehicles (EVs) in many countries. It seems the transition to EVs is now accelerating rapidly with several traditional car manufacturers joining Tesla in the EV market, and some governments in Europe banning the sale of new internal combustion cars by 2030 or 2035. Increased environmental awareness of the customer base, together with the quietness, simplicity, low maintenance, reduced running costs and smooth operation of electric motors has finally forced the automotive world to sit up and take notice of the utility of electrons for automotive propulsion.
In contrast, on the water recreational fishers are not unfamiliar with electric motors. Use of a bow mounted electric has been a popular option for anglers fishing in freshwater, estuary and inshore areas for around 2 decades. Over time the use of electric motors has become widely recognized as one of the best ways to reduce the noise you generate underwater, giving fishos the benefit of greater fishing success by allowing them to sneak up on unwary fish. Not only that, the fact that electric motors are beneficial to the aquatic environment through the absence of combustion products emitted into the water is also acknowledged by legislation in various states that allows only electric powered boats to fish in water supply impoundments.
The truth is even though the emissions of internal combustion engine (ICE) outboards and inboards have improved markedly in recent decades, they still vent all (or most) of their exhaust into the water, dispersing hydrocarbon based pollutants as well as CO2 (which acidifies water). Because of this, pollution from outboard engines remains a significant problem in heavily used waterways. It was these concerns about pollution and the broader issues with the need to reduce dependence on fossil fuels, together with improvements in battery technology and electronics which has prompted recent efforts by some manufacturers to dip their toes into the water by designing electric motors to use as the primary propulsion system for boats. So has the time come for the Electric Boat (EB)? Can you now run your runabout entirely on electricity?
One example is Pathion Marine Energy, a group that has utilized lithium-ion battery technology and inboard electric motors to greatly reduce fuel usage in large watercraft ranging from 20 foot rigid inflatable boats to displacement vessels over 100 meters long. Their technology is a bit like a marine hybrid, with the option to use electric drive as a range extender for diesel engines, (using the diesel engines to charge the batteries while the boat is underway), or even to run on battery-electric only for a shorter range of up to 50 nautical miles on a single charge. They advertise their current 70 foot R&D vessel (with 480 KW/h of power) as having “quiet operation making it valuable for military or law enforcement stealth operations”, as well as an environmentally friendly alternative for “sensitive areas for sustainable harbor transport”.
Oceanvolt are another supplier of all electric and hybrid inboard/outboard solutions for motor cruisers and sailboats, even providing a 40 foot hybrid passenger catamaran and an all-electric displacement cruiser with a top speed of 15 knots and 80 nautical miles range. On the outboard front there are now several options available including the Torqeedo outboards with equivalent of 25 hp worth of thrust, and the Aquawatt range which advertise “the world’s most advanced electric outboards” with units up to 50 kw /70 hp. Electric motors have high torque at low RPM, which makes them useful for application where high thrust is required, so a 70 hp electric outboard is more than enough to get a small to medium sized runabout up onto the plane, opening up the possibility of a proper electric boat which could appeal to fishos looking for that extra edge in quietness on the way to their favourite spot. Perhaps in the not too distant future the option of an electric motor as the primary propulsion system for your next fishing boat may not be as outlandish as it presently sounds!
And for those who think that there is no way that electric propulsion could be scaled up to a level that works for ocean going container ships, there is the container sized battery concept being promoted by Phoenician Energy. Their truly innovative concept revolves around supply of highly energy dense aluminium-air batteries in 20 foot containers, that would be loaded onto container ships together with the cargo. Each 20 foot battery contains a massive 4.8 megawatt hours (MWh) of energy (around 4 times the energy density of current state of the art lithium-ion batteries), and they can be stacked and joined to allow a modular Lego-like battery system to provide sufficient energy to propel an entirely electric powered container ship over many coastal shipping routes. At the end of each trip, the depleted battery is not charged, but instead is offloaded with the cargo and replaced by a new fully charged battery. The depleted battery is then recycled into a new aluminium -air battery by replacing the aluminium. The alumina generated from the depleted aluminum recovered from the battery is easily recycled back to aluminum at the aluminum plant, which can result in an extremely low carbon footprint when renewable energies are used in a truly circular economy. Battery boats ? Watch this space.
