While at sea, sailing boats require auxiliary power for a range of on-board equipment. Power
requirements are in the region of 500W. Currently, rechargeable batteries are used to power
such equipment. However, batteries will provide sufficient energy for no more than a day at
best. An in-board diesel engine is usually available to generate electrical power and recharge
battery banks. However, running the engine without engaging the propeller drive shaft while
sailing, is known to be detrimental to the condition of the engine and noisy for the passengers
on board.
Specialist stand-alone diesel generators have become popular for boat owners seeking to
address the increasing demand for more power on their vessels. Specialist diesel generators
have many drawbacks: costly; unreliable in rolling seas; require regular maintenance; noisy;
produce harmful environmental emissions; and have high running costs - especially since the
removal of an EU tax exemption on fuel.
A range of alternative power solutions also exist, but these are ineffective. Micro-wind
turbines become redundant when sailing due to down wind conditions, while solar panels are
inoperable during periods of darkness and require large amounts of boat deck surface area.
Hydro-generator technology is a promising emerging area for the given application, but the
leading products in this sector currently lack the power output needed at typical cruising yacht
speeds. They are also prone to reliability issues and are considerably costly (£3500).
This project proposes the development of a novel hydro “Power Pod” capable of generating
the required 500W at cruising knots (6kt) and with a retail price of £1500. Higher power
output will be achieved through a specially developed generator and superior reliability will
be realised using a novel water isolated motor design.