Better things are electric........

[Tony]

In Claus Riepe s "SUZUKI 2.5" thread – (a discussion of suitable engines for the BR) - it is suggested that electric propulsion isnt really practical as yet. Im not sure  that the problem is in the technology  (or lack of it ) I think perhaps its the demand for suitable applications thats lacking. Once mass production, economies of scale and the threat of fuel tax as a cure for Global Warming make hybrid and electric CARS  more desirable, perhaps there will be spin off technology suitable for small boats.

Available NOW are:-

*briefcase sized generators
*efficient and powerful electric motors
*computer controllers for battery and charge management
*decent batteries – unfortunately either too heavy or too expensive
*shore power – many only 13amp rather than 50 amp so slow recharge times
*battery charging by tow vehicles when trailing to launch sites

A great deal could be done with the above by a half decent engineering firm that wasnt frightened of salt water or bankruptcy. ....but would I put MY money into such an enterprise?
Many electric boat fans seem to think that 3 hours at full power is good going. Not me! Especially not if it takes all night on Economy7 to re-charge. What mass of battery would be needed to hold enough charge for a week or two away from the mooring? (My CBL sails best in a wind with either 90kg of lead or a fat bloke lying in the bilges. 90kg of batteries instead will be no hardship but, somehow I think it might not be enough!) 
What of  the (so called) alternative technologies,then? 
Most,if not all, small sailing boats spend more time on the trailer or mooring than they ever do motoring.  Surely we can do something creative with sun, wind and wave power * during this down time?
Why not have all three generators built into your mooring buoy and simply plug in after a days sailing? Could you not store charge in batteries in the mooring buoy for use/transfer when you tie on? Would this provide enough juice? It would save lugging the batteries off to the nearest 3 pin socket every night.
Would it be possible to take the mooring buoy/ charging unit away with you to the next mooring? That would save on storage capacity if you want to be off on your travels for a couple of weeks.

*Solar cells have improved recently – and become relatively cheaper.
Wind  generators (fan type) tend to have too many moving parts, needed in order to face the wind. What happened to the vertical axis type?
Wave power – the only application for small boats I have seen is a  pump  hung over the side using air pressure and valves to empty the bilges as she rolls.

Was it General Motors or EverReady that suppressed the patents on electric vehicle technology in the sixties? Perhaps Fiat might think more to the future!

[Tony]

Annoyed at the unreliability of my 4hp petrol outboard motor, I would like to examine the possibility of a conversion to electric propulsion.


Requirements:


    *

      Totally reliable – switch on and go.
    *

      Marinised and water-proofed.
    *

      Large diameter, slow revving, weed-free prop. Easily replaced in event of breakage -no sheer pin.
    *

      Remote throttle and steering an option.
    *

      Remote batteries an option
    *

      Enough battery capacity to run for at least 4 hours per charge at 5 knots – minimum, even against wind and tide, giving a theoretical range of 20 NM. (My 4 hp petrol outboard pushes the boat – 300kg of Cardigan Bay Lugger and camping gear - at about 6 knots)
    *

      Physical mass of batteries needed not to exceed c. 80-90 kg – preferably much less.
    *

      Batteries should be easily transportable and removeable for charging ashore – no individual element of the system to weigh more than, say, 15-20kg.
    *

      Batteries fully recharged in as small a time period as possible, say 4 hours tops.
    *

      Option to rapidly charge batteries in situ using marina shore power, or small, on-board petrol generator.
    *

      Option to trickle charge with solar or wind power while on a mooring or while being trailed to new launch site.
    *

      Initial purchase price of system to be less than £1,000. (Ha Ha. Wipes tear from eye..)
    *

      Battery life to be at least 1,000 cycles.
    *

      Annual maintenance cost (ex-batteries) to be zero.


Having seen Mini Kota trolling motors and Torqueedo outboards in action I'm not totally convinced that they are up to the challenge.


Can anyone suggest possible solutions?

[Terry Cross]

Hi Tony
It seems that we have been thinking along the same lines.
I have a 18ft sailing cruiser (Eagle 525) with a 4hp petrol outboard fitted in a well which works very well.  The problems I have are when sailing and manoevreing.
When sailing the outboard well causes so much turbulance as to take 1.5 to 2 knots off the speed.
 I cannot adjust the engine to run slow enough to manoevre in tight places.
  After successfully using the electric outboard on Iona for the last few weeks I got to thinking it could be the
the way to go on the Eagle.

Here are some first thoughts (not Solutions) based on your list of requirements.
 As I am more practical than technical some of the ideas may be "way out"  How do you convert LBs thrust to horsepower? Do you use a Shire or a Shetland?

Motor
  I think the most sensible way is to buy a motor "off the shelf"
The largest appears to be 86lbs thrust. Not marinised. (max boat wt. 1900kgs).
The largest seawater one is a 44lb thrust. Is this powerfull enough?
The replacement props are cheap (£20) and easily replaced but do have a sheer pin.

Remote
   The throttle is a simple electro mech. switch which could  easily be removed and resited or duplicated for dual control, wiring (including supply) through a caravan type plug.
Some motors have a remote foot operated throttle
   
Steering
    I was thinking of leaving the engine in a fixed position and steering with the rudder.
As you suggested earlier a "push me pull me" cable could be fitted. Probably to the tiller.

Batteries
    These I know very little about
You could leave some of your lead ballast out to compensate for the weight of the batteries.
The one I use on Iona is 120ah, about 20kg, stored and carried in a bag with a shoulder strap (an old cooler bag)
For the Eagle I am thinking of a pair of smaller ones.
I shall also carry my suitcase generator, which seems to be a good idea as submarines have been doing it for years

Hope this helps regards Terry

[Paul Cross]

Hi
You both might want to read the Nov/Dec copy of Water Craft magazine which has an article on the cirrus daysailer. This is a very attractive 20 ft daysailer with an electric auxillary saildrive from a company called Sillette. Also has a folding prop for when you actualy want to sail!!.They claim 4-6 hours at 5.5 knots.

The unit is obviously designed as a through-hull installation but i dont see why it couldnt be permenantly fixed into a modified outboard well.

I've no idea regarding batteries, cost etc but they may be the people to talk to rather than embarking on a winterlong design and development program......give me a call when you've both got it working and i'll come for a test sail. 

Sillette sonic saildrive link http://www.sillette.co.uk/elect_saildrives.pdf

Has anyone considered using a fixed prop like this to generate a charge whilst sailing?...I would have thought you could recharge your cells through the motor pretty quickly on a good lengthy broad reach..or...even better...whilst moored overnight in a tidal channel..... or a river.....or whilst towing down the motorway at 80!!!!

[Julian Swindell]

I do not think the perfect electric motor is anywhere near here yet or we would all know about it. There are systems which drag the prop to spin the generator, but they slow your boat down and are not that effective. I think you need a fairly heavy boat to make them work. Battery technology is the other killer. It was mother nature's joke that the best element for storing electrical energy is lead. Why didn't she choose aluminium? She must hate boats...
There are ideas of fixing the actual motor unit, which is really quite small, to a rudder blade. Then all the controls you need are the tiller and a forward and back switch. The Lithium ion batteries seem best for storage (give Mother Nature her due, lithium is even lighter than aluminium, maybe she does love us after all) but they are really expensive at the moment for the size a boat needs.
Mind you, I have so much grief from outboards that I expect that if I got an electric one, it would just electrocute me each time I tried to start it.

[Terry Cross]

Browsing through electric outboard sites I came across this one which displays all the technical info. I think you will find it interesting.
http://www.floveroutboard.co.uk/outboards.html
Terry

[Terry Cross]

PS Try the "Buy on line/choozamotor" Tab

[Julian Swindell]

Thinking further, Torqeedo may be more advanced than I had realised. I have just been looking at their web site and the bigger Cruise models seem to have a lot going for them:
http://www.torqeedo.com/en/hn/products/cruise-r.html
On my boat, the batteries may not be so much of a problem. I carry 400kg of water ballast, so a great chunk of that weight could be given over to batteries. A problem would be loss of variable ballast but I tend to sail with a full ballast load most of the time, and you would still have some water to chuck out.
The second problem is that the prop is big, 300mm diameter. This would not fit through the current outboard opening, but that could be solved with a saw and some epoxy.
Apart from cost (they are expensive) the big problem I see is how do you recharge the batteries? I keep my boat on a swinging mooring, so shore power is no good. Could solar panels really do it? What sort of area would you need?
I still find a problem with looking at all those solar panels, banks of heavy batteries, hours of recharging, huge cost and then looking the 12 litre petrol tank which would probably take me 200nm and take 5 minutes to refill at the fuel barge. I still don't think electric power is there yet if you sail on the sea like I do.

[Tony]

Hi, Electric Folk.
(Er...Sorry. Didnt mean to invoke Steeleye Span....)

Paul;
Yes, I saw the Cirrus article ....and was impressed enough to contact www.Bellman.nl - the manufacturers- to look at their range of motors.
 It seems that a suitable motor for my boat would cost 3-4,000 Euros - gulp - then a dirty great Lithium battery  would cost about the same. Then the prop and transmission - and then the charge controller ....and then....and then...
I was somewhat taken aback by the mounting cost and (foolishly) mentioned the Torqueedo being only (ONLY? Good Grief!) a thousand pounds. 
This was the e-mailed response:-

“Our products you can’t compare with Torqueedo, with all respect, we are producing Propulsion systems to use every day, also professional.
So we don’t use Plastic and we don’t use a drilling machine motor with some plastic toothwheels to reduce the propeller speed.
Our motors producing Torque straight on the shaft and we are using Stainless steel and seawater resistant aluminum etc.
Again with all respect we are producing Propulsion systems in a complete other range.”

Ouch! Well, Im sure they are  right, but this is early adopter money, innit. Unfortunately I dont have the cash to join this group...in fact  wouldnt bother about electrics at all if my professionally serviced, petrol filtered, greased and pampered 4 stroke could be relied upon not to let me down at the crucial moment. (Who ever heard of a modern Yamaha, Suzuki or Honda car or motorcycle stuck at the side of the road because of a blocked carburetor jet? Whats the matter with these guys!) Use the things every day and they can be fine, perhaps, but the point is that we DONT. Used infrequently and they contravene the Sale of Goods Act. They are not fit for purpose!
If it turns out that I can only afford a glorified egg whisk over the stern, so be it......so long as the damn thing works  when Im caught in a 3 knot tide with no wind!
Well. Thats got THAT off my chest!

Julian;
Yes, charging will be a big pain... and range is an issue... but wouldnt you rather have a reliable 10 nMiles (if, indeed, these electric systems ARE reliable) than to be caught out unexpectedly?

Terry;
Thanks for the http://www.floveroutboard.co.uk/outboards.html   link. £250 for a salt water 55lb thrust motor is certainly worth a look. Same as a 2hp petrol motor or the Torqueedo travel. (60 days to work it all out before VAT goes back up to 17%)
Has anyone seen these motors in action?


Cheers!
Tony

[Julian Swindell]

Just going back to this electric motor thread. I was quite taken with this image from the Woodenboat Forum. The poster said the best bit was moving around with apparently no means of propulsion

[Michael Rogers]

It's probably quite natural that topics in one part of this forum converge from time to time on other themes elsewhere. That is by way of preamble, because I shall be mentioning the BR17 (current hot topic in the 'General' section), and also because I'm not sure how strictly 'technical' my contribution is. I want to suggest that better things, in some circumstances such as running out of basic motive power (wind), are not necessarily electric. This is a variation on the 'wooden topsail' theme.

I learned to sail in the Colne Estuary, and am old enough to have watched, as a small boy, the dwindling post-war fleet of working Thames barges, most of the time still under sail. A sight for sore nautical eyes was the way bargemen would handle the open boats - up to 16 ft long, clinker-built, and certainly much heavier than a Swallowboat -which the barges used as tenders. These boats were sculled with a single (straight-bladed, obviously) oar in a notch in the transom, and both the speed and the manoeuvrability achieved had to be seen to be believed.

Some years later, as a teenager in the 50s, a friend and I set about learning how to do this (actually in Gorran Haven in Cornwall). To start with it was infuriating - the oar kept jumping out of the notch: then quite suddenly the knack came (like riding a bike), and with a bit of practice one could belt along (relatively) and also manoeuvre in tight places in harbour. The movements of the oar handle involved are difficult to describe, but essentially it is a figure of eight with subtle twists the while. Great fun and most effective.

I haven't done it for years, but believe the knack would still be there. One can't scull a double ender (which rules out my Storm Petrel and all the Storms), and I doubt whether one could scull round or alongside a mizzen mast (the 'tiller' element would be hampered). The Trouper would probably be beautiful to scull. So would the BR17, except that Matt's drawings suggest, and I suspect all you Bay- and Sea- afficionados assume, she will be ketch rigged. You're all obviously keen on mizzens for good reasons which Claus, among others, has extolled in these pages. It's outside my experience, so I can't comment. However, let me so provocative as to suggest that a sloop-rigged BR17 could be sculled back to port when the wind drops.

All is not lost, ketch-wise. One needs a relatively long oar, leading to stowage problems? A case for a two-piece oar loom? Or - and this is my idea-to-be-patented-and-then-the patent-given-to-Matt - the mizzen mast of your BR17 could double as an oar loom-and-handle, and once the mizzen has been stowed and unshipped, could screw into a suitable blade (2 1/2 ft long, easily stowed), making up an oar for sculling with no obstacle in the way of the notch in, or oarlock mounted on, the transom. Problem solved, and the best of both worlds?

Electric outboards - who needs 'em?

[Julian Swindell]

I'm interested in sculling as I don't think the dimensions of the BayCruiser would allow easy rowing. There is no need for the sculling notch to be central, and often it isn't. Having it off to one side makes it easier to stand alongside the oar. It is easy to compensate for the slight off-centredness by a stronger compensating stroke. You can scull a double ender just as easily, with an oarlock screwed somewhere at the back of the boat
The other answer is to go the whole hog with a Chinese Yuloh. Storing the oar could be a problem, but maybe along the side deck? I would be intrigued to try one.

[Terry Cross]

Hello Michael
I trust your move went according to plan.
Sculling? In double ended gondols they do it standing up.

Electric outboards - who needs 'em?
I did last Autumn on "IONA". Up a lazy river,good company,sunny day,no wind,sails furled,motor on tickover, no noise to disturb the wild life,glass of wine in one hand,tiller in the other.
Who could ask for anything more?
Terry Cross

[Michael Rogers]

Julian, thanks for your erudite contribution on sculling - you obviously know much more about it than I do! I am thrilled with the idea of sculling a double ender, didn't know you could. Distinct possibilities there. For various reasons (mainly rowing position vis a vis daggerboard case position) rowing a Storm Petrel is problematic, although she skims along under oars. Sculling now, that IS an idea. And where can I get info about a yuloh? I recall an article in Water Craft about it - the writer made his a functional work of art, as I recall.

Incidentally, if this sculling thing continues, maybe we should start a new thread?

Terry, yes thanks, the move was relatively straightforward: AND come the Spring and some quite minor building work, I will have a much better workshop!

[Michael Rogers]

PS  Lesson 43 1/2 - before you bother people on the forum with a question, google it and you'll likely get an answer. I googled yuloh and it will take me a while to digest the wealth of information which magically appeared (including on sculling).