This 30ft sailing yacht originally fitted with a diesel sail drive leg, needed new propulsion as the old engine was no longer an option. Working with the customer we engineered a solution to get the boat sailing again ready for the 22 season.

Given the hull design and existing sail drive, the obvious answer here was to adapt the existing propulsion leg to suit electric. We selected the 10Kw motor from our Belt Drive range. For economy, size and simplicity. Being air cooled its smaller than the liquid cooled equivalent power - (Direct Drive range)
This motor proved to be a great choice and the relative damp free bilge of a GRP boat poses no concern to the air cooling.

Motor Selection

At the beginning of 22, battery technology was facing lengthy lead times, so a Lead AGM battery was selected, this was available within the time frame but also fitted with the low spend goal we were working to. 4 x 12V200ah batteries were chosen and fitted nicely beneath the salon bunks down below. This pack delivers approx. 10Kwh total and 5-7Kwh usable. Plenty enough for the very sailing experienced owner. After all this is a saling boat…!
A basic shore power system was fitted to suit the 1000w DC charger for when alongside.
A critical part of the system was for the boat to be off-grid. Living most of the time on a swinging mooring, the boat had to be able to charge the propulsion batteries. Solar PV was opted for with 4 x compact and dense mono-c panels 120w each. These are being trialled with great success on the coach roof and fitted nicely. Though shading form the boom does effect the output somewhat, there is still enough to charge the modest battery bank to 100% over a sunny weekend from 40% charge state. Alternative panel positions and set ups are being planned by the owner.

Battery and Charging

Nigel Waller

"Lightning Craft provided me with the ideal engine solution, fulfilling my requirements with range, power and solar recharging. An absolute pleasure to deal with this company"

This 30ft sailing yacht originally fitted with a diesel sail drive leg, needed new propulsion as the old engine was no longer an option. 

SAILING YACHT

This 1950’s 4 meter wooden speed boat was built with a 10hp Ford side valve engine. But years gone by has seen the engine become uneconomical to repair. The owner opted for a re-power and decided on a B-Drive system. To suit the unique power requirements of this project, we modified one of the aluminium frames to take a larger liquid cooled ME motor, adapted the direct shaft coupling, and fitted the original coupling to join the prop shaft with original propeller to the new unit.

A liquid cooled version of the 10Kw motor used on our B-Drive10 was used on this project. The liquid cooling allows the motor to run harder for longer, increasing its continuous and peak power ratings. This increased power was needed for the boats planning requirements. This motor was fitted to the B-Drive frame and running a 1:1.17 ratio belt pulley had a final shaft speed of 2,500 RPM and motor output speed of 3,000 PRM.


Having undergone a stunning restoration by the owners the best solution to the batteries was Lead AGM - explained below;


The best solution to power the boat would have been to use LiPO4 batteries, due to their light weight and high output current, but cost was prohibitive. So, lead acid AGM batteries were chosen as the energy storage solution in the interim (until lithium batteries become more affordable). Four Yuasa L36-AGM batteries were fitted in series to give a nominal 48 Volt output

The first run of the boat, with the new propulsion, showed that the output was not quite up to the potential, the boat could only achieve 12 knots, a shaft speed of 1600RPM and electrical power consumption of 8kW. The excellent support offered by Lightning Craft was requested and Josh provided a solution to have the motor controller tuned using a remote (mobile 4G) connection while the boat was on the water. This tuning enabled the controller to get as much out of the batteries as possible (15.5kW)

First run - electric power!

Robert McPhee and Trevor Deacon

"Lightning craft offer a very flexible design capability, they have significant knowledge and experience of the system and the support they offer made them the best choice for this conversion."

This 1950’s 4 meter wooden speed boat was built with a 10hp Ford side valve engine. But years gone by has seen the engine become uneconomical to repair.

SPEED BOAT

Belt Drive

Canal Drive

Direct Drive

Wide-beam canal boats, heavy workboat launches and large yachts.

Narrow boats up to 60ft with 10Kw. (or full wide beams using 20Kw)

For dayboards and smaller yacht diesel inboards

The largest of the three motors in our *DD* range, popular on the canal scene in the largest wide beams and adventurous 60ft narrows.

Liquid cooling for a longer life, higher efficiency, and best performance.

Mounted on a steel frame with adjustable mounts allows the unit to fit into a range of different engine bearers when converting. Or for production and new builds we have designed the feet around standard 370mm centres. 

Controlled from an electric throttle and key switch through a lightweight and slim harness with minimal limit on length.

General Arrangement

Technical Drawings

Direct Drive 20

20kW high torque 48V DC, inboard electric boat motor for sailing and power vessels, narrowboats and wide beams

These motors are a liquid cooled and operate on 48V DC. Liquid cooling allows them to be highly efficient, long lasting and high performing.

Mounted on a steel frame with adjustable mounts, allows the unit to fit into a range of different engine bearers when converting.

Controlled from an electric throttle and key switch, bulky and stiff engine and gear leavers are a thing of the past.

Direct Drive 10

10kW high torque 48V DC inboard electric boat motor for sailing and power vessels, narrowboats and wide beams

An alternative to traditional stern tube and shaft seal arrangements.

This kit offers a propulsion drive-train system.

A weld-in steel tube of 120mm OD is fixed into the swim end in position of the shaft centre.

Inside this thick wall steel tube is a bronze bearing carrier and thrust bearings that holds the prop shaft and shaft seals all in one. The heavy duty bearings take care of all the axial and radial loads of the propeller and motor, reducing the noise of the drive system and improving performance.

On the inboard end of this unit an adapter flange is fixed followed by the propulsion motor.

This assembly provides an extremely compact stern gear and propulsion system. On average this assembly is 75% shorter than a traditional stern tube assembly and diesel engine. 

Not like the traditional greaser type shaft seal, which cumulatively pumps tones of harmful grease into the waterways every year from all the boats still using them.

The robust construction and twin lip seals mean the maintenance of these units are very little. 

Should servicing be needed, seals and bearings are held in stock and can be renewed. (though this is not expected for at least 5 years+).

Canal Drive 20

20kW 48V DC electric motor and stern tube propulsion for canal boats and steel hulls

This versatile power unit is great for day sailing yachts and keel boats, picnic launches and light-duty power boats.

Being air cooled allows no skin fittings making it faster and simpler to install. Pulleys and toothed belts are used to transfer the torque form the motor to a 25mm stainless shaft that runs through the base of the chassis, held through 2 frame bearings that handle all the radial and thrust loading from the propeller. 

Designed for shaft driven propeller boats.

Choose from ratios to match common diesel gearboxes. (2.4:1) and (2.7:1) (for custom ratios please contact)

The target RPM for the prop shaft has a range of 950-1300 RPM. This can be programmed to suit existing propellers and stern gear capacities.

Inbuilt safety features include: Stall torque cut back, overheat, over torque, and over speed protection.

Belt Drive 5

5kW belt drive 48V DC electric motor for boats. Ideal in small yachts and launches, day boats and light duty work boats

Canal Drive 10

10kW 48V DC inboard electric boat motor and stern tube propulsion for canal boats and steel hulls

A powerful small boat electric motor, these motors are a liquid cooled and operate on 48V DC. Liquid cooling allows them to be highly efficient, long lasting and high performing.

Direct Drive 5

5kW high torque 48V DC inboard electric boat motor for sailing and power vessels, narrowboats and wide beams

This versatile power unit is great for small yachts, powerboats, picnic launches and light-duty work boats.

Belt Drive 10

10kW belt drive 48V DC electric motor for boats. Ideal in yachts, launches and work boats

Canal Drive 5

5kW 48V DC electric motor and stern tube propulsion for canal boats and steel hulls

Our Motors

Converted Builds

Carter 30

River Speed Boat