Are Electric Boat Motors Any Good?
Yes, electric boat motors are efficient, environmentally friendly, and offer quiet operation, making them a good choice for many boating activities. However, their suitability depends on the boat’s intended use and individual preferences.
Over the course of my 10-year career in boating and yachting, I have used more traditional combustion engines than I care to remember.
And when the time came to try out electric propulsion for the first time, I vividly remember thinking just how positive the overall experience was!
For fairness, I’ll address the negatives. But I strongly believe the marine industry’s electrification is the most exciting development in a generation!
👍 Benefits of Electric Boat Motors
The talk of the town at the moment is converting fossil-based fuel systems to those powered by renewable energy.
On the one hand, the proponents of electrical energy (as an available renewable energy source) vitriolically proclaim that electrical power is the way forward.
On the other side of the fence, you have those resisting change who vehemently explain that electric motors are not the panacea of all the world’s environmental issues, nor is the technology advanced enough to replace gas-powered motors on a one-to-one basis.
So, where is the truth in the matter?
Let’s look at each of the advantages and disadvantages and let you make up your own mind.
Environmental Impact
The biggest factor both sides raise is the environmental impact converting electricity as a power source offers to the environment.
The Environmental Benefits Of Electrical Power
The benefit to the environment seems self-explanatory at first glance. Electric motors run on – you guessed it – electricity! As such, it is a zero-emission power source.
There are no gaseous emissions, and they are quieter, reducing noise pollution (more on this point later).
Recharging involves no potential for petrol or diesel spills, and the risks associated with recharging are substantially reduced. By that, I mean there is zero chance of a fire occurring.
What is there not to like?
The Environmental Disadvantages Of Electrical Power
While it is true that using electric motors is emission-free and, therefore, beneficial to the environment, this is not the whole story.
1️⃣ Mining of Lithium and Cobalt
The environmental and social damage caused during manufacture and end-of-life disposal is substantial.
Lithium-ion is the most efficient battery technology (current state of the art). The largest supply of the raw materials for Lithium-ion batteries is from mines in Central Africa and Russia.
Human rights organizations have identified The Central African mines as providing horrific working conditions for its laborers, many of whom are children. The mortality rate in these areas is horrific.
Although Russian mines may not be guilty of these human rights abuses, the current political situation is not ideal.
2️⃣ The manufacturing process
Manufacturing batteries and, where applicable – solar panels are environmentally costly and produce substantial harmful emissions.
3️⃣ Disposal Of Batteries
At the end of life, the batteries have to be disposed of. Although many companies offer a service that dismantles and restores some components, the basic battery cannot be refurbished or reused.
This is a problem for which there is currently no optimum solution.
Precision Operation
Controlling the power output of an electrical motor is much more accurate and simpler than an equivalent gas-powered unit.
Throttles measure the power as a straight line from stop to full speed. When power is applied, there is no hesitation, and the acceleration thrust is immediate.
Noise and Vibration Reduction
The good news for the proponents of electric motors is that there is no comparison between internal combustion and electric motors regarding noise and vibration.
While no smell is quite as emotive as a 2-stroke outboard engine powering you along, you quickly get used to the silent, effortless experience provided by an electric motor.
A slight hum is produced at their loudest, which is easily drowned out by the pleasant sound of the bow cutting through the waves.
There’s no vibration or sound when the boat is “idling.”When stopped, the electric motor is silent. Many anglers have already found the benefits of this with electric trolling motors, where they can sneak up on the fish in complete silence.
Energy Efficiency
Electric motors are considerably more efficient at lower power ratings than the equivalent gas-powered unit.
In the low-powered electric outboard motor market, the motors convert between 35% and 50% of the battery energy into propulsion power. Trolling motors convert 18% to 22% of their battery energy into propulsion power.
On the other hand, in a gas-powered outboard motor, only 20% of the fuel (defined as chemical energy) is converted to mechanical energy. Of this, only 5% is used to run the engine and get the power down to the prop shaft.
By the time the energy rotates the propellor, only 15% is available.
Low Operating Costs
An electric motor’s capital (acquisition) cost is generally substantially more than a gas-powered outboard motor.
But once the motor has been paid for, the cost benefits are substantial. Get a deeper understanding of how electric boats work to evaluate their efficiency.
“Gas” Mileage
Not only are the raw energy costs (cost of electricity vs. cost of gas) substantially lower, but most states provide significant rebates and other benefits for using electricity.
The fuel savings cost is significantly lower because electric motors are more efficient.
Maintenance Costs
Gas engines (irrespective of whether they are 2-stroke or 4-stroke) require constant maintenance to continue operating well.
They include fuel systems that can become contaminated, hydraulic lines that wear, electrical generators (alternators) that need work, and complex drive systems that may be damaged.
When winter comes around, the boat is laid up, and the conscientious owner will need to winterize the gas-powered motor to prepare for its seasonal hibernation.
The simplicity of electric motors is one of their chief advantages. You need to look after the battery and keep it stored safely and regularly charged, which is also required for batteries used with gas-powered systems.
Apart from that, no fuel systems, alternators, ignition systems (spark plugs, etc.), or hydraulics can wear or become contaminated.
The only systems that require care are to ensure there is no mechanical damage to the motor or its peripheries and, as discussed, to care for the battery.
👎 Disadvantages of Electric Boat Motors
As discussed earlier, although electric motors have many advantages over their gas-powered cousins, they are not a panacea for the marine industry.
They have weaknesses and areas where they do not compete well with the gas-powered equivalent
Limited Range
While the motor’s ability to generate propulsion from the available battery power is more efficient than a gas-powered engine, batteries contain less energy than a typical gas tank.
This means that the finite range available to an electric motor is generally less than an equivalent boat powered by a gas-powered motor.
Charging and its Related Infrastructure
Added to the limited range is the fact that charging is less efficient. A gas-powered boat owner can simply stop at a gas pump, open the tank, and fill it with gas – quickly and easily.
The same does not apply to an owner with a boat powered by an electric motor. To recharge the boat, the owner has to find a suitable charging unit (of which there is generally inadequate infrastructure).
If no charging point is available, it means taking the boat out of the water (or removing the battery) and finding somewhere on land to recharge it.
I have also had many instances where I have stopped to help a fellow boater who has run out of gas.
All I had to do was hand them my spare jerry can of gas, and they could restart and be on their way. The same flexibility simply does not exist for electric boats where the battery has gone flat.
The charging process is the area that I have had the most difficulty adapting to after converting to an electric motor. The other issue that affects me (maybe more than others) is the concept of range anxiety.
The range is more easily managed with a land-based electric vehicle where conditions are more easily controlled.
On a boat, an oncoming current, high wave state, or inconvenient wind direction affects the potential available range.
Higher Initial Costs
Electric outboard motors and their related battery storage systems (battery, charge controller, and possibly an inverter) cost substantially more than a gas-powered outboard motor.
Midlife updates, where the battery has maxed out the number of cycles and needs to be replaced, are expensive and should be considered when comparing the costs.
Ultimately, you need to gauge the longevity by learning how long an electric boat motor lasts and see if the maths makes sense for your budget.
⚖️ Comparing Electric vs. Traditional Boat Motors
The two types of motor (electric vs. gas-powered) provide very different experiences, and deciding on the route you choose will need to consider your personal circumstances.
Power Output
Low-powered electric motors provide a reasonably similar cost per horsepower.
It is often difficult to compare the two as gas-powered motors state the power output in horsepower, whereas electric motors are rated in Kilowatts (kW).
The conversion rate used to calculate kilowatts as a horsepower value is 0.7457 kilowatts per horsepower.
To make it easier, the following table converts the kilowatt ratings of engines and compares them to the equivalent horsepower.
| HorsepowerInternalCombustion Engine | The Equivalent Power Rating In Kilowatts |
| 1 hp | 0.7457 kW |
| 5 hp | 3.7285 kW |
| 10 hp | 7.4570 kW |
| 20 hp | 14.914 kW |
| 50 hp | 38.285 kW |
| 75 hp | 55.928 kW |
| 100 hp | 74.570 kW |
| 150 hp | 111.855 kW |
| 200 hp | 149,140 kW |
| 225 hp | 156.782.kW |
| 300 hp | 223.710 kW |
| 350 hp | 260.995 kW |
| 400 hp | 298.280 kW |
| 450 hp | 335,566 kW |
In terms of performance characteristics, you can expect an electric motor to provide high values of low-end torque. This will produce better acceleration than the equivalent gas-powered motors.
Gas-powered motors tend to have higher top speeds than the equivalent electric motor.
Maintenance
This is discussed previously, but in summary, an electric motor requires a small percentage of the maintenance needed by an internal combustion engine motor.
The electric motor has fewer parts and systems than internal combustion engines. As a rule, an electric motor requires a small percentage of the maintenance requirements of a gas or diesel-powered motor.
Long-term Investment
Because electric marine motors have not been around for long, the jury is still out on which represents the better investment.
Electric motors should hold their value longer because they don’t have as many parts to wear. This may be subject to the following factors.
- The electric motor market continues to grow, and the share of electric motors in the marine market is expanding. If this happens, it will create a viable secondhand market, which will prop up prices.
- A great long-term user experience with electric motors is needed to make them a sought-after product.
- The price of fossil fuels (oil) continues to rise, so many factors influence the price of oil.
- An alternative technology is not launched that supersedes the benefits of electric motors.
🎖️ Popular Electric Boat Motor Brands
There are more than 25 manufacturers of electric motors that supply the United States. The three brands that are best known are:
Torqeedo
Torqeedo offers electric outboard motors from 1hp to 80hp, which can be specified for fresh and seawater.
The Torqeedo’s outboard motor range includes the following products.
| Model | Horsepower |
| Ultralight 403 A/AC | 1.0 HP |
| Ultralight 1103 AC | 3.0 HP |
| Travel 603 | 2.0 HP |
| Travel 1103 C | 3.0 HP |
| Cruise 2.0T | 2.5 HP |
| Cruise 3.0T | 6.0 HP |
| Cruise 6.0T | 9.9 HP |
| Cruise 12.0T | |
| Cruise 12.0 R Torq Link | 25.0 HP |
| Cruise 12.0 FP Torq Link | 25.0 HP |
| Deep Blue 25 | 40.0 HP |
| Deep Blue 50 | 80.0 HP |
Elco
Elco produces electric outboard motors in the 5hp to 50hp category.
Elco has been in business since 1893. The technology used by Elco uses a three-phase induction motor with no commutator or brushes.
The result is that there is a single moving part. This makes the Elco range more durable than Gas power and Direct current (DC) motors.
The Elco range includes the following products.
| Model | Horsepower |
| EP-5 Electric Outboard | 5 HP |
| EP-9.9 Electric Outboard | 9.9 HP |
| EP-14 Electric Outboard | 14 HP |
| EP-20 Electric Outboard | 20 HP |
| EP-30 Electric Outboard | 30 HP |
| EP-50 Electric Outboard | 50 HP |
ePropulsion
The ePropulsion direct drive range of outboard motors was launched in 2014 and concentrated on low-power units.
| Model | Horsepower |
| Spirit 1.0 Plus | 3 HP |
| Spirit 1.0 Evo | 3 HP |
| Spirit 1.0 Evo Remote | 3 HP |
| Navy 3.0 Evo | 6 HP |
❓ Frequently Asked
Can electric boat motors be used in saltwater environments?
Yes, many electric boat motors are designed for both freshwater and saltwater use. However, it’s crucial to rinse the motor with fresh water after saltwater use to prevent corrosion and prolong its lifespan.
Are there any specific safety precautions to follow when using electric boat motors?
Safety precautions for electric boat motors include ensuring all electrical connections are secure, regularly inspecting the motor for any signs of wear or damage, and avoiding overloading the boat. Additionally, always ensure the battery is charged in a well-ventilated area to prevent any potential hazards.
