Case Study: NB Felonious Mongoose


NB Felonious Mongoose is a XXft semi trad built in 2008 with a Beta 43 Hybrid system and a larger than usual 890Ahr battery alllowing several days of Electric cruising between charges. The owner often cruises overnight charging at Marinas and other locations to extend the diesel free cruising even further.

Felonious Mongoose was featured in Canal Boat June 2009 Edition

Customer Feedback

"Felonious Mongoose has been used to explore the English and Welsh navigable canals and waterways, making as little use as possible of the diesel engine.

Total miles 2009 and 2010, 1805 miles, with a total diesel engine use (for all purposes) 231.8 hours. Assuming 3mph on when running the Diesel this gives 695 miles on diesel and 1106 electric miles. Diesel has only once been run for half an hour for charging along side the canal bank – I have ignored this in the calculations. At all other times diesel use has been for both propulsion and charging. Further extrapolating from these calculations, assuming 2.2 mph when using the electric motor, this gives 503 hours for electric propulsion".

Charley and Dolores Johnson

The owner also notes that when operating in the tidal parts of the Thames he was very glad to have the full power of the engine available.

System Details

Engine:  Beta 43
Hybrid System: Single electric motor
Battery: 890Ahr @ 48v Flooded Lead Acid Traction Cells with common watering and gas venting system. 2-3 days Electric Drive Autonomy
Electrical System: Dual Victron Energy Multiplus 48/3000/35 - 70A DC charging and 6Kw AC Power
Monitoring: Victron BMV602

NB Felonious Mongoose is fitted with the Hybrid Marine Standard Inland Waterways Narrow boat (single Electric motor) package with a 890Ahr battery allowing 2-3 days of Electric Drive Autonomy and sufficient 230v domestic capacity.
Battery monitoring is by a Victron BMV 602 which provides a "fuel gauge" for the battery.