Outboard versus Inboard Electric Boat Motors: A Comprehensive Comparison

Electric motors have revolutionised the boating and marine industry by providing Outboard and Inboard electric motors that are clean, quiet and efficient alternative boat motors to traditional diesel and petrol powered engines. Outboard and inboard electric motors are two of the most popular types of electric motors for boats.  

In this article, we will sail into the differences, pros, and cons of these two electric motors, to help you make an informed decision when choosing the best motor for your boat.

Types of Electric Boat Motors

These engines come in many shapes and sizes, with inboard and outboards being the two main types and electric trolling motors being the mini version of the outboard motor and mainly used for fishing and recreational boats such as kayaking and canoeing.

Inboard motors are installed inside the hull of your boat and the motor is attached directly to the propeller shaft. Outboards are mounted on the back of your boat, on the transom, and have an external propeller. 

Electric inboards are becoming increasingly popular due to their clean operation and low emissions compared to combustion engines, while the outboard version offers more power for smaller boats such as sailboats or yachts.

Electric inboard boat motors are available for larger boats as well, providing powerful electric propulsion yet efficient option for powering your vessel. Electric outboard boat motors provide a lighter alternative to traditional outboard motors, giving you more control over your speed and direction.

What are the Key Differences Between Inboard and Outboard Motors?

The key differences between inboard and outboard motors are their location on the boat, how they are powered, and their speed.

Inboard motors are placed inside the boat, while outboards are mounted on the outside of the boat. Inboard engines have an extra component, which is an internal transmission connecting to a propeller shaft that runs down into the water. Outboards have a motor attached directly to the propeller in the water, making them much lighter than inboards.

In addition, inboard motors usually have more power than outboards and can reach higher speeds. On the other hand, outboards tend to be less expensive and easier to maintain than inboards.

All in all, both types of motors provide efficient propulsion for any size of boat and offer different benefits for different needs.

Outboard Electric Motors

Outboard Electric Motors are mounted outside the boat and are attached to the transom. They are usually smaller and lighter than inboard electric motors, making them easier to install and remove. Electric outboard motors are also more manoeuvrable, allowing you to steer the boat more precisely.

Advantages of Outboard Electric Motors:

• Easy to install and remove
• Lightweight and compact design
• Increased manoeuvrability
• No need to access the inside of the boat for maintenance
• More affordable than inboard electric motors

Disadvantages of Outboard Electric Motors:

• Limited battery capacity compared to inboard electric motors
• Shorter range due to smaller battery capacity
• Higher risk of damage due to exposure to the elements.

Inboard Electric Motors

Inboard Electric Motors are mounted inside the boat and drive the propeller through a shaft that runs through the hull. They are larger and heavier than outboard electric motors, but they offer more power, a longer range and a quieter operation. 

Advantages of Inboard Electric Motors:

• More power and longer range
• Quieter operation
• Better protection from the elements
• Easy access to the motor for maintenance

Disadvantages of Inboard Electric Motors:

• More difficult and time-consuming to install
• More expensive than outboard electric motors
• Reduced manoeuvrability due to the larger size and weight of the motor
• Require access to the inside of the boat for maintenance.

When to Choose an Outboard Electric Motor?

Outboard Electric Motors are ideal for smaller boats, such as dinghies, inflatable boats, and kayaks. They are also ideal for anglers and divers who want a quiet and environmentally friendly option for their fishing or diving trips. Outboard Electric Motors are also a great choice for people who want to save money on their boating expenses.

When to Choose an Inboard Electric Motor?

Inboard Electric Motors are ideal for larger boats, such as sailboats, motor yachts, and houseboats. They are also a great choice for people who want more power and a longer range, as well as those who value a quiet and smooth operation. Inboard Electric Motors are also ideal for people who want to protect their motor from the elements and have easy access to it for maintenance.

Charging the Battery for your Electric Motor

There are several methods to charge the marine battery on a boat’s electric marine motor:

• Solar Panel: If you have a solar panel installed on your boat, you can use it to recharge the battery whilst  on the water.
• AC Charger: You can use an AC charger to charge the battery while you have access to shore power in the marina.
• DC Charger: A DC charger can be used to charge the battery while you’re on the water. They are usually portable and can be powered by a 12-volt cigarette lighter socket.
• Generator: If your boat has a solar generator, you can use it to recharge the battery.
• Engine-driven Charger: Some boats have an engine-driven charger that can recharge the battery while the engine is running.
• Wind Generator: If you have a wind generator installed on your boat, you can use it to recharge the battery.
• Hydro regeneration: Mariners may also want to think about choosing an inboard electric motor with hydro regeneration capabilities. These electric engines can recharge the batteries while the boat is sailing.

FAQs

Q: Are Outboard Electric Motors more environmentally friendly than Inboard Electric Motors?

A: Both Outboard Electric Motors and Inboard Electric Motors are environmentally friendly, as they do not produce any emissions of pollutants. However, Outboard Electric Motors are generally considered to be more environmentally friendly due to their smaller size, lighter weight, and lower energy consumption.

Q: Which type of electric motor is easier to maintain?

A: Inboard Electric Motors are easier to access for maintenance, as they are mounted inside the boat. However, Outboard Electric Motors are easier to remove for maintenance, as they are not integrated into the boat’s structure. Both types of electric motors require regular maintenance to ensure optimal performance and longevity.

Q: Can Outboard Electric Motors handle rough water conditions?

A: Outboard Electric Motors are designed to handle rough water conditions, but they are more vulnerable to damage due to their exposure to the elements. Inboard Electric Motors are better protected from the elements and are less likely to be damaged in rough water conditions.

Q: Can Outboard Electric Motors be used for longer trips?

A: Outboard Electric Motors have a limited battery capacity, which means they have a shorter range compared to inboard electric motors. While they can be used for longer trips, they may require more frequent recharging stops. Inboard electric motors have a larger battery capacity and a longer range, making them a better option for longer trips.

Conclusion

Outboard Electric Motors and Inboard Electric Motors both offer unique advantages and disadvantages. The type of electric motor that is best for you will depend on the size of your boat, your boating needs, and your budget.

If you’re looking for a compact, lightweight, and affordable option, Outboard Electric Motors might be the right choice for you. If you want more power, a longer range, and a quieter operation, Inboard Electric Motors are a better choice.

No matter which type of electric motor you choose, you can be sure that as a boat owner, you will enjoy a clean, quiet, and environmentally friendly boating experience.