What an amazingly good idea!!!!
With a few caveats and qualifications I think a lot (maybe a majority) of cruisers would be better off with this idea. The caveats/qualifications are:
Low Latitude Sailors --
Less likely to have long overcast periods. No high latitude sailing.
My Sort of Cruising --
Never leave port when strong winds are forecasted. Very rarely leave port when the forecast
is headwinds. If you are going even partly around the world, go west - less headwinds even on long passages. Rarely or never motor
at maximum speed.
Apples against Apples --
You need to define the starting point for any comparison. The base I have used for comparison is an Outremer
45 like Jimmy's boat
but fitted out conventionally for a boat of this type - 2 diesel engines, 2 saildrives, genset, solar panels
and (say) 600 A/hr of house battery
These are the changes to go from the base defined above to Jimmy's boat --
Compared to the base above the main differences are: Add
motors for propulsion
, a water generator
and 400 A/hr to house batteries
; Take Away
2 diesel motors. I think a saildrive
for an electric motor
would cost about the same as a saildrive
for a diesel.
Comparison - Capital Cost --
I don't think there is much difference. I think suitable electric
motors would be less expensive than a diesels (this reduces the capital cost) but you need the water generator
and it would be sensible to increase the house battery
capacity (these increase the capital cost).
Comparison - Operating Cost --
A hands down win for the electric solution. No fuel cost, significantly reduced maintenance
Comparison - Handling Nasty Weather Under Motor Only --
I would expect that the conventional solution could punch to weather
in higher winds than the electric solution. At a guess a conventional solution might stop being able to go to windward when the wind
strength rises to 35 knots; the electrical
solution might stop at 25 knots wind
Comparison - Range Under Power Only --
A clear win for the conventional solution. Under benign conditions the conventional rigged boat may be able to go 500nm; my guess for the electric boat with the genset running would be 250nm.
Comparison - Top Speed Under Power Only --
This might be 11 knots for the conventional configuration compared to 8 knots for the electric. Top speed under power is a question that is often asked. However in 6 years of full time liveaboard
cruising I have never had both engines at WOT to achieve top speed under power. I have never been in a situtation that needs it.
For me --
the low operating cost is the glaring advantage. The deciders for me however is are not technical.
Firstly I love not having a diesel engine
on and resent starting a diesel engine
. More peace and quite.
Secondly I value very highly not having to worry about refueling, buying maintenance
consumables (this is a hassle in remote
locations) and doing the routine maintenance. I like having more things in the category 'I don't have to think about that'. Cruising always involves having a lot of things you need to worry about. I vote for a change that would reduce the length of the worry list.
One last point. The Outremer
base reference is obviously a highcost starting point. Most cruisers would start at a lower cost. I have not done any calculations for a comparison starting at a lower cost so I don't know if that would affect my conclusions.
Lets hear from you.