What do you need to know about electric boats?

There is barely a week that goes by without some manufacturer expanding on its electric boat portfolio as the hunt goes on for what may one day replace fossil fuels on recreational boats.

But what is an electric boat, and what do they mean for potential users? What are the obstacles to using them, and what are the potential benefits?  

Electric boat technology is still in its infancy, but it is slowly starting to make inroads to mainstream boating – following a similar path to how electric cars have been slow to gain momentum among car buyers.

Here is the boatsales.com.au guide to how an electric boat could one day fit into your world.

Just like cars, there are two types of electric boats; purely electric boats powered only by electrons, and hybrid boats that use fossil fuel engines but tap into electricity to help them reduce the conventional engine emissions.

Car-makers are largely leading the development of purely electric boats, with some boat bands tapping into battery systems developed by car-makers including Tesla and Toyota to help them get a head-start on the water.

The benefit of a boat that incorporates electricity in its propulsion is that instead of relying on the fuel bowser, batteries can source their power from a number of sources including wind, solar or even hydroelectric generators.

For boats that use a hybrid diesel-electric set-up, the batteries can recharge as the boat moves along under conventional power, saving the silent-running and emission-free part of the journey for where it is most beneficial.

Batteries on board a boat can come in a number of different forms, including lead acid, nickel-based and lithium-ion.

Weight is an important factor in boats, so boat-makers looking at introducing electric motors to their vessels tend to go for lithium-ion batteries that can pack in energy much more densely than the other forms of battery, but can weigh up to a third of the weight of a traditional lead acid battery.

The other benefit of lithium-ion batteries is that they can take less time to charge than conventional batteries, but only if the specialised chargers that can speed up the process are available.

Another benefit of lithium-ion is that they tend to have more charge cycles than conventional batteries, meaning that while a traditional lead acid battery may last five years under ideal conditions, a lithium-ion one will last double that.

While lithium-ion batteries are more expensive to buy than more traditional batteries, the fact they last longer than traditional batteries tends to flatten the extra cost out in the long run.

You also have more options when packaging a lithium-ion battery compared with a traditional one. Lithium-ion batteries can be built long, flat and wide and don’t mind being tipped upside down, whereas lead-acid batteries tend to be bulky and cannot be tipped over.

Another big advantage of lithium-ion batteries is that they come with software built into them that helps to maximise battery life, just like a smartphone. The software can manage the battery’s discharge and even shut it down to protect it if there is too much power going out of it.

If you want, you can go out and buy a purely electric boat today. Brands such as Greenline, sold in Australia by eyachts, already offer buyers the choice of a H-Drive diesel-electric hybrid system that can provide around 25 nautical miles of battery-powered motoring.

Next year, another of eyacht’s brands, Axopar, plans to bring an all-electric day boat to Australia. Meanwhile, another European boat brand, Candela, has made inroads into New Zealand and is yet to jump the ditch to Australia to sell its foiling electric motor boat.

Expect more to come, and for the technology to apply to bigger boats. Volvo Penta, one of the largest recreational motor yacht engine suppliers globally, has unveiled a new range of engines that are designed to run as gensets, powering electric motors that turn the propellers and recharging onboard battery systems.

Anyone looking for smaller engines need only look at the likes of Yamaha and Mercury which have announced they will produce electric outboard engines.

The biggest hurdle to owning an electric boat is education. While boat owners tend to know much about conventional engines powering their craft, they know little about using electrons to do the same job.

A survey from US new and used boats listing group Boatline claims that two out of every five people shopping around for a new boat were exclusively looking at an electric powertrain, while one out of three was also considering if a hybrid system would suit their needs.

The main driver is the low impact that electric boats have on the environment compared with conventionally engined ones.

According to the survey’s results, only 27 per cent of people searching for a new boat were looking to buy a petrol-powered one.

However, when it comes to buying an electric boat, only 16 per cent of those surveyed said they were interested enough to consider one now, while one in three said they’d maybe consider one.

If you look overseas, governments are starting to force boat owners to upgrade to vessels that can run on electricity alone for at least part of the journey.

This is similar to the car world, where countries such as the United Kingdom, Germany and even China have created low-emission zones that ban cars that have exhaust emissions.

In the on-water version, some marinas globally are starting to discourage boat owners from relying fossil fuels to motor in and out of their berths, giving added weight to hybrid diesel-electric boat engines as a viable option.

The main appeal for anyone buying an electric boat, according to Boatline’s survey, is the fact that they are quieter – something commented on by half the people shopping for a new boat.

Surprisingly, the desire to save money on fuel was less important to potential buyers, as was the fact that electric boats were effectively emissions-free and needed less maintenance.

However, almost one in five potential electric boat buyers were attracted by the idea that having a battery-powered vessel would put them at the cutting edge of technology – something that electric car brand Tesla has traded on.

There are downsides to owning an electric boat. Surprisingly, boaters surveyed showed they were more concerned by the amount of time it would take to recharge an electric boat than its range.

Also high on boaters’ radars is the lack of recharging infrastructure. There are no power points out on the water, and few options allowing boaters to plug in while they have lunch at a marina before heading out on the return journey.

Another barrier to buying an electric boat appears to be the cost. As with electric cars, electric boats do tend to cost more to buy than their fossil-fuelled rivals.’

However, while the first Tesla Roadsters cost more than $200,000 when they launched more than a decade ago, you can now buy a basic Tesla Model 3 for around $70,000.

The other factor, too, is that current battery technology doesn’t really lend itself as a catch-all solution for the boating industry.

For example, while a 15hp electric motor is fine for a tinny nosing around an estuary for a few hours, there’s no purely electric substitute yet for a boat fitted with twin 300hp outboard engines that is heading 40 nautical miles offshore to fish the continental shelf.

A large part of Australia’s recreational boating industry is based around people and families jumping onboard their boats and heading out fishing.

If electric boat technology can evolve to include this group of people, it could be enough to help battery-fuelled boats gain critical mass and start to put pressure pon their fossil-fulled equivalents.