The Case for 48V DC Windlasses in an Increasingly Electric Yachting World

Typical 12V DC Windlasses

Introduction:
As the boating industry experiences a gradual shift from traditional diesel and gas engines to electric propulsion, there is a growing need for manufacturers of yacht windlasses to provide options for 48V DC systems in addition to 12V DC systems. With the increase in popularity of electric propulsion, yachts are better served by adopting 48V DC systems for their high-power loads, such as windlasses and bow thrusters.

Why 48V DC?

The windlass is a relatively high power load on a boat’s 12V system, typically ranging in power from 600W to 1500W. When re-powering a yacht with electric propulsion motors, a 48V DC system presents an excellent choice (especially when the propulsion system is 50 kW or less). The lower voltage is much safer to work with and it doesn’t require any special certifications or additional expertise, beyond knowledge of the standards of marine electrical equipment. Most electric propulsion systems in yachts utilize 16S LiFePO4 batteries, which has a range in pack voltage from about 40V DC when totally discharged to about 57V DC when totally charged. The industry now refers to this as simply, 48V DC.

Existing Electrical Systems on Yachts:
Currently, most yachts utilize a 12V DC system to power a majority of their on-board systems, such as cabin lighting, cockpit equipment, navigation systems, depth finders, navigation lights, refrigerators, and cabin water pumps. When re-powering a yacht with a 48V DC system, it is necessary to maintain a 12V power supply for these existing systems. This can be accomplished by installing a DC-DC converter that down-converts the 48V input to a 12V output. Similarly, AC loads that use inverters can be supported by products that invert from 48V power, such as the Victron Quattro.

Challenges of Large DC Loads:
However, large DC loads like windlasses, which can draw up to 125 Amps from 12V, cannot easily or cost-effectively be powered by DC-DC converters. A separate 12V battery is needed to power these loads, adding complexity for charging and monitoring this additional battery. If windlass manufacturers were to offer 48V motor options for their equipment, the need for a separate 12V battery could be eliminated, simplifying the overall system and reducing costs.

The Case for Bow Thrusters:
Bow thrusters, another high-power load on yachts, should also support 48V options for the same reasons. Transitioning to 48V systems for both windlasses and bow thrusters would lead to a more streamlined and efficient electric propulsion system on board.

Embracing a New DC Voltage Standard:
Recently, Tesla proposed a shift in the automotive industry from the decades-old 12V standard to a 48V standard, citing the need for modernization and improved efficiency. With the world moving towards better battery technology, such as LiFePO4, it is time for the marine industry to embrace a new DC voltage standard of 48V, especially for high-power equipment on board yachts.

Conclusion:
The yachting world is undergoing a significant transition towards electric propulsion, and it’s time for manufacturers of yacht windlasses and bow thrusters to provide 48V DC options. By embracing a new 48V DC standard for high-power equipment, the marine industry can ensure a more efficient and streamlined integration of electric propulsion systems in yachts, ultimately benefiting boaters and the environment alike.