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Talbot
10-01-04, 19:56
I intend to have both a large solar panel and a duogen in order to meet my power needs, but can only afford one this year, What do you all recommend as the first?

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ccscott49
11-01-04, 10:32
depends where you are, meddy solar, caribean, wind, NW Europe wind. Not sue about those duogen thingys.

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boatmike
11-01-04, 11:51
I have no experience of wind generators apart from being anoyed by them on other peoples boats while at anchor. I have however been very pleasantly surprised at the performance of solar panels. With 2 panels about 2ft square linked directly to a dedicated service battery bank I have been able to run a fridge pretty continuously while not aboard and keep my general battery state topped up to 14 volts. AND THIS IS IN THE UK!
Admittedly they are expensive (cost me about 800 to install including regulator etc.) but I get about 3 amps pretty continuously on an average summer day and when the sun comes out in earnest 5 to 6....
I would guess that in the Med the fridge will consume more power than in the UK but the sun comes out more too so I would personally go the solar route.
I am not yet a livaboard expert and would of course listen to the experiences of those who are. There are two things that put me off windy gennies though. 1. Noise (I like my peace and quiet) and danger (dont want a big rotating food blender on my boat). Also there are no moving parts to maintain on a solar panel!
I also reflect, what is the most reliable in the med? Wind or light levels? Not much difficulty answering that one! While I have not yet lived on a boat (but will start this year) I have sailed in the Med and Caribbean and I have always had either too much or not enough wind, while the days of bright light (contrary to popular belief solar panels don't run on heat from the sun they run on light) has remained constant.
No contest in my book. Install the solar panels. Get them as big and as many as you can afford. Try it out for a season and my guess is you will not want the windie at all......


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boatmike
11-01-04, 12:04
By the way. I have just seen you sail a cat. I sail a Prout Snowgoose. Another good reason for solar panels. You are not sailing with any appreciable lean (I hope!) and they are always pointed vaguely upwards. Monohulls going to windward lean over (poor misguided lot) which causes them to have to keep moving their SPs around. You won't but DEFINITELY buy 2 and mount them on the coachroof Port and Starboard to optimise performance when motoring or sailing.
My boat is ashore in Northney Marina currently. If you want to come take a look send me a PM!

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ccscott49
11-01-04, 13:04
What you need solar panels for when motoring?

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Talbot
11-01-04, 14:38
Cause my engine is a diesel outboard and only has a 10 amp charger. But iyt is 27 hp, light weight and I can hydraulically lift it out of the water for sailing. I can alsio reach the propellor from the stern without getting into the water (when it is lifted)

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Talbot
11-01-04, 14:43
I plan to have a single 170w panel mounted on lugs above the dinghy davits. This minimises the distance to the batteries. The Catalac shape is not quite so appropriate for a coachroof mount. I was in Northney year before last and was appalled by their bills - I vowed never to go there again. Need for all the power is that I have eberspacher, and will be fitting bow thruster and 1000w windlass as soon as I can get out of the water (dont ask - a long saga of broken promises)

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ccscott49
11-01-04, 14:47
10 amp charger is pretty good! From an outboard. I didn`t ask about the hydraulics or the other reasons for having an outboard, but good idea anyway!

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ccscott49
11-01-04, 14:49
170 watt panel, that would do nicely, but I bet it isn`t cheap, I`ll wait until I go to the states before I buy a solar panel.

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charles_reed
11-01-04, 15:47
I've got both.

Choosing between one or the other I'd go for Solar panels first as they're rather more consistent.

You do need both in the long run.

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boatmike
11-01-04, 16:44
Quite right I don't.
I should have perhaps said when either under sail or not. i.e. at anchor perhaps.
However even under engine I let the third battery stay under solar charge to allow my other main (second) service battery and the first traction battery used solely for engine starting to take all the available charge from the engines alternator. With a "smart" regulator on the engine this allows the battery that is sensed to be the battery that is being charged. If I am getting 6 amps free from my SPs I don't want to waste it. Running a fridge from the engines alternator unnecessarily when it could be giving a full charge to the other batteries is wasting power during the relatively short periods it is running.
Depends of course on the boat. How often and for how long you motor and your own philosophy on battery management.

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ccscott49
11-01-04, 17:05
When at anchor, I run the genny for three hours every two days, also make water at the same time.
When at sea I have a motor sailer, so I have at least one engine on, and alternate them every six hours. So have plenty of energy available to charge batteries.
I have a smart reg, on my stb engine which charges the domestics, 550 ah at 24v. Then the port engine charges the engine start, without a smart charger as it`s not required.
I use a sterling battery management panel to check the health of all batteries, I also have 2 x 12v batteries for genny start, which are charged through a charger. I have considered solar and will fit two 85-100 watt panels, when I get to the states, to assist my energy requirements, finding somewher to put said panels might be a small problem and at 7 mps, i could do with at least twice that panel size. but 4 @ 5-600 pounds each, that buys 1800 gals of diesel about 10 years of diesel for my genny. A wind genny same thing and unreliable constant source, although again I intend to fit one..
My boat is very power hungry and I find this works for me, I dont go into marinas, except in the (cheap) winter, I liveaboard all the time. 2 fridges, freezer, watermaker etc. I see no reason to rough it and find the cost of the diesel to generate my own leecy and water works not an excessive outlay. Different strokes for different folks.

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boatmike
11-01-04, 17:16
Agree all MDL Marinas are expensive. Less so ashore than afloat though and their travel lift is wide enough to take the cat so for 3 months ashore not too bad. Agree that Eberspacher needs a lot of power to run the fan etc. Also when you need it you will be in the cold dark winter maybe when the solar panel won't keep up too well. This might be a logical argument for wind power unless you are tucked up in a marina with shore connection which makes solar and wind power redundant anyway......
I personally feel that the bow thruster and anchor windlass are not a consideration as you would have your engine running before using either of them surely?

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boatmike
11-01-04, 17:21
Totally agree, different strokes for different folks. I like to sail and only run engines when absolutely necessary. Nasty noisy smelly things! Just goes to show we are all different. Would be a boring old world if we were not!

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boatmike
11-01-04, 17:25
p.s. also agree as far aft as possible if you have a single panel is good to avoid sail shadow when under way.

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ccscott49
11-01-04, 19:05
There talks somebdoy that knows little about engines, they do not have to be smelly or noisy. with the right instalation, but I too like to get them shut down, but in the meddy you had beter realise you are not going everywhere by sail alone.

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Talbot
11-01-04, 20:15
yes engine will be running, and power output for the max 3-4 mins of use is not a big consideration, but a windlass can use a lot of power if you have a lot of cable out, or want to re-anchor. In anycase I have done a thorough power budget and believe that the mix that I have will be correct for the boating I will be doing, and as a back-up I have a small generator.

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boatmike
11-01-04, 20:15
And there speaks someone purely looking for an argument it seems.
I will make 4 points only and then shut up.
1. You are talking to a Marine Engineer with 40 years experience of designing, installing, and maintaining marine diesel engines. I am not prejudiced against them I just prefer to sail
2. I try to inject some humour in to the proceedings. Obviously not in your case appreciated.
3. Although I have no actual livaboard experience on a small craft in the Med as you do I have sailed extensively in the Atlantic, Pacific and Indian Oceans over a period of some 40 years both professionally as crew and as a sailing enthusiast. I know the Med very well. I also know I will need an engine and will have to use it extensively if I go there.
4. If you go back to the beginning of this thread the original question was NOT confined to that shallow pond it was general. There is a bigger world out there than the Med you know!
There is no need to be so ***** aggressive !!!!!

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ccscott49
12-01-04, 06:06
Anything but aggressive, it seems I am misunderstood, I apologise if I have offended and no need to swear, even if it is ######. I too am an engineer, not a marine engineer, but certainly know quite a bit about small marine diesels, and have sailed and motored for more years than I care to remember, also all over the world, so...... Anyway, the meddy is where I am now, could be in the caribbean or west coast of the states this year or next, who knows. I have lived aboard on and off for 25 years. Also my original answer was also not confined to that not very shallow pond. I too will now shut up, here anyway.

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boatmike
12-01-04, 08:37
Yes that's the important thing of course. Everyone's boat, philosophy of use, and sailing area will be different. If you have already done a power balance budget you know best what your requirements are. One can only generalise. You are also correct to be more concerned about secondary charging methods if you only have a limited charge rate from your outboard.
The bow thruster and windlass are indeed some way from your battery and even assuming you will indeed be running them with the outboard charging, the power loss in the cable is a factor. One solution to this is to fit a dedicated battery in the bow. This way the charging cable does not need to be as massive as the power cable would be to reduce the voltage drop to acceptable limits. The disadvantage is that it makes the charging circuit more complicated. If you don't want to fit a second battery have the biggest cable you can and don't forget to fit a marine quality circuit breaker to protect it in the chance of short circuit. Some of the dinky ones sold in chandlers are a menace. I have seen more electrical fires caused by overloaded windlass wiring than I would like to recall...
Best of luck either way. Remembering your original question and recognising I am possibly giving you other advice you did not ask for now (and probably don't need anyway), I still think you should try the solar panel first before you buy a wind charger. You may be pleasantly surprised by the result. Don't forget it will be charging ALL the time there is light. During the summer months I get an average of 84 amp/hours per week from mine which is more than I expected in the UK......
Enjoy your sailing and best of luck whatever choice you make. Too much charging capacity never caused anyone a problem!

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Talbot
12-01-04, 10:43
Thanks, had already considered battery placement, and will be using a single 110 amp/hr carbon fibre lead/acid at the bow dedicated to the thruster and windlass. As you say, the size of the current likely to be running down the charging line is not enormous, because of the available power! Battery size is a trade off of weight against CCA, but I have been advised by a specialist that this should be OK.
My wish is to have a system that will be independent of engine charging, both at anchor and whilst sailing. I will be changing all nav lights to LED, and a selection of interior lights as well. I will also be using keel cooled Fridge/freezer.
The circuit breaker supplied with the windlass is a 100amp, the fuse for the Bow Thruster is 250 amps. The maximum heavy cable length for the bow thruster is 2m (probably less than 1metre) and is 60mm.
I have yet to decide on cable size for the windlass, but it will be a bit longer(max 3 metres) so probably in the order of 50mm.

I will see how much discount I can wring out of Barden at LBS!

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AndrewB
12-01-04, 12:10
I've had wind generators though never a solar panel. I'm hoping not to have to fit a wind generator again. Neither of the two I owned ever delivered as much power as advertised, even in trade winds. Although quiet at first both became progressively noisy and caused vibration through the boat, so that they tended to get turned off at night. The advantage was they were much cheaper than solar panels. Even so, I doubt whether they were actually economic over their useful lifespans compared with simply running the engine alternator for longer. Now I'm no longer a liveaboard, I'm sure they wouldn't be.

I'd like to fit solar panels next time I head out, but am again concerned that they wouldn't really be cost effective, even if environmentally friendly.

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boatmike
13-01-04, 17:54
All sounds eminently sensible. Suggest fit breaker rather than fuse on thruster but thats a detail... All goes to show how many different ways there are to skin a cat! (no pun intended) I know the batteries you mean. Good choice as they give a good compromise between "traction" and "deep cycle" and light weight. Barden supply them also by the way if you didn't know. I use one as engine start and windlass. For service batteries deep cycle wet lead acid ones but thats just my preference. Very interested in your LED lights. Can you get enough power to be visible 3 miles? Where do you buy them from then? Or are you converting standard fittings to LED yourself?


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Talbot
13-01-04, 18:14
At the moment I have AquaSignal 25 as nav/stern/steaming light and an AquaSignal 41 Tricolour. The 25 series use a 10w bulb (=1 mile vis) the 41 uses a 25w bulb (=2miles vis) I plan to replace all with at least 2 mile vis.

My original preference was for http://www.deepcreekdesign.com/tristarpage.html (http://www.irisoft-yacht.com/led/IRISoft-LEDs-fiche-public-HT-IRISoft-en.pdf>http://www.irisoft-yacht.com/led/IRISoft-LEDs-fiche-public-HT-IRISoft-en.pdf</A>) are technically the best (and the only ones at the moment able to supply the 25w bulb replacement)), but are very expensive.

I am hoping that <A target="_blank" HREF=http://www.orcagreen.com/ArgoNavisInserts.cfm>http://www.orcagreen.com/ArgoNavisInserts.cfm</A> will complete their range before I really need them.

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catmandoo
13-01-04, 21:41
where does one fit a bow thruster on a cat ?

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catmandoo
13-01-04, 21:44
why do you have to make water while running the genny . Does it make you nervous ?

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timevans2000
14-01-04, 16:38
I agree with the other post here. Go for solar panels first. I have a pair of 64 watt panels on my coachroof. I get excellent results in the summer.

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Talbot
14-01-04, 17:22
I will be fitting a single thruster in the port bow. This has already been done by a chum using a Vetus 55, and he reports that it works fine up to at least 20kts of wind on the beam. I looked at the Vetus and rejected it because of the width requirement - I would have to fit it too far aft from the bow for what I wanted. I discovered that the Sidepower 40 requires only 30% of the Vetus width, and the tunnel is smaller in diameter as well. Yes I know that on paper it has less power than the Vetus 55, However I will be fitting it at least a foot further forward, and that should solve that, and in a test I have seen the Vetus only acheived 44 kg of thrust anyway. At the same time I will be fitting bulbous bows, which should assist the water flow as well.

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catmandoo
14-01-04, 17:40
under what circumstances would you use it ? Do you not have props on each hull which would produce the same effect ?

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catmandoo
14-01-04, 17:54
Sorry just remembered you had a single central outboard . Presume you cant use this as effectively as having two drives . even with 180 degrees rotation

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Ric
14-01-04, 22:06
One advantage of solar panels not yet mentioned is that they are incremental so you can easily add more when budget and need dictates. With a wind-generator, if you buy one too small it is very expensive to upgrade it as you have to sell the first and buy another.

I would advise you to get a couple of solar panels, see how you get along with them. I would also advise getting an amp-hour counter at a relatively early stage, as that will give you a much better understanding of what you need and what you are getting. Defintely buy an amp-hour counter before getting a wind-generator as otherwise you risk ending up mistakenly buying too small a wind generator.

Wind generators are by no means all noisy. Only the Air-Marine is really noisy, The Aerogen range are relatively quiet, and the Rutlands really don't make any annoying noise at all (well mine doesn't).

I think the Duogens look rather dodgy and inefficient. If you must get a dual-purpose generator, get an aero-aqua4gen from LVM. It is a proper wind-generator when in wind mode, and a good water generator too.

I am in the Med and have both solar and wind and both are very useful, particularly at anchor. They are less useful when sailing as the sails shadow the panels and the wind generator loses efficiency on some points of sail. I would like to add an aqua4gen at some point to provide good power on long ocean passages.

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Talbot
15-01-04, 09:21
I can only move the outboard through abt 30 degrees each way, which is fine if there is no wind, but if there is wind, it can get a bit fraught! - parking on a pontoon when the wind is blowing off can get very interesting /forums/images/icons/smile.gif

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Talbot
15-01-04, 09:26
Suggest you read the specs for the duogen versus the aqua4 - no comparison. You are also not towing shark bait behind you. Besides it will fit much better on my boat. I have done the energy budget to ensure that I am going to have sufficient power for all my needs (now and future) and thus buy the correct kit initially. Thus the solar panel will be a 170w panel sized to be fitted above my dinghy davits (and thus clear of the sail shadow).

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Ric
15-01-04, 09:43
Yes I have read the specs and I agree that they show that the duogen produces more power. However, I am very suspicious of the specs of the duogen - frankly I don't believe them. According to their specs, in wind mode it produces more power than dedicated wind-generators of similar size like the Rutland 903 or the Aero4gen, despite having rather primitive untapered blades and a power-sapping right-angle in the power transmission shaft, and a tail-fin that I doubt is powerful enough to hold the fan into the wind on a rocking boat. Also, in water mode it is sited very close to the rear of the hull and I am suspicious about how much the impellor stays in the water in a sea. I'd believe their specs if I saw them backed by an independent test but have never found one.

All manufacturers of wind turbines, solar panels and water generators exaggerate their figures, or at very minimum establish them in totally unrealistic perfect conditions. They never produce in reality what is claimed. But I find the duogen's figures less believable than most - I bet their wind figures were measured by strapping it to a car, blocking the tail in position, and driving at a steady speed down a runway - a measurement that is totally irrelevant to the gusty and rocking mounting on a boat. I bet they also measured the water-mode current by running it in undisturbed water at the bow of a motor-boat on a lake, and not off the back of a sailing boat in a heavy sea.

I would buy the Aeroaqua4gen because I know that LVM is a reputable company, their products are well designed, and I regularly meet satisfied owners. I have yet to meet a duogen owner - have you?

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Talbot
15-01-04, 11:21
yes - 2 (both very satisfied)

In any case I have now decided that the duogen will wait for a couple of years (while bank recovers from all the other purchases /forums/images/icons/smile.gif) which will give me a chance to gather more data from duogen users.<P ID="edit"><FONT SIZE=-1>Edited by Talbot on 15/01/2004 11:23 (server time).</FONT></P>

timevans2000
15-01-04, 14:32
Have you actually seen a Duogen yourself? This product is very well designed and engineered. I looked at all the wind generators at the Southampton boat show. The Duogen, in my opinion, is head and shoulders above the rest.
The only one that comes close is the Pacific 100. This looks more durable.
The rutland, by comparison looks fragile, although I have heard good reports about this unit.

I have had feedback from one user of the Duogen who has crossed the Atlantic. He was delighted with his Duogen and had no problems.

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Ric
15-01-04, 17:54
No I have never seen one and only base my comments from looking at their website. But I am an aero-engineer, so tend to look quite critically. I would welcome being proved wrong, as I have in the past considered getting one myself. But I just found their reported output rather surprising. Combine that with the fact that I have never yet seen one actually sold to a real-life customer (and I always look at wind-generators on boats - one of my favourite subjects) led me to be a bit cynical. I'd still welcome an explanation as to how their claimed output with rather unsophisticated looking constant pitch blades (judging from the pics), fed via a power-sapping right-angle joint, can beat the power output of (say) a similarly-diametred Rutland 903 which has blades that change in pitch the length of the blade. Wind-generator output figures are one of the most easily-massaged statistics out there, so I tend not to believe them at all unless I have seen them verified in a fairly rigorous back-to-back test via a reputable magazine (and not one that carries lots of ads for the winning product in the same issue!!!)

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Talbot
15-01-04, 19:51
The blades are quite a bit bigger (longer) than either ampair or rutland, which must make a bit of a difference. The only one that I have heard off which has failed was on the singlehanded Pacific rower's boat, but as that boat was pitchpoled and rolled several times, I dont suppose you can moan about that! /forums/images/icons/smile.gif

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timevans2000
16-01-04, 11:37
I have a Duogen, purchased at the Southampton boat show. I am in the process of installing at the moment.
Why do you assume the right angles joint is power sapping? You are unlikely to have ever seen a joint like the one Duogen uses! I hadnt, and I am an engineer too.
The Rutland is a smaller diameter than the Duogen and as I am sure you know, the square law plays an important role when diameter increases a little, so increase in performance of Duogen is to be expected. The Duogen is 1.1 metre as opposed to 0.91 metre.

I dont doubt the performance of the Duogen in wind mode. Duogen were giving away a nice little anenometer at the boat show to actually measure the wind speed over the deck so you didnt have to guess. Wind speed at the mast head is often 30% more than at deck level. I supsect this is why people are disapointed by the performance of their wind generator rather than untrustworthy figures.

The performance of the unit in wind mode was not my main reason for purchase. I am interested in the turbine performance. This is vastly superior to the competition.

I suspect most people would purchase this unit primarily for the turbine, otherwise you can buy a wind only generator like the Rutland for a fraction of the price

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JerryHawkins
16-01-04, 13:06
...I've had it since just after they launched and it has been updated as the design has evolved. I'm extremely pleased with it and can confirm the output figures they quote!

My initial reason for buying, apart from ease of switching between water and air mode, was the fact that the bulk of the weight (the alternator itself) is kept at deck level and not perched on top of a long pole.

Feel free to ask any specific questions you may have and I'll try and give an unbiassed opnion! If you are in the Plymouth area any time I''d be pleased to show you the unit in action.

Regards, Jerry

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Talbot
16-01-04, 18:15
/forums/images/icons/smile.gif Smug mode from feeling vindicated /forums/images/icons/smile.gif With my intended program, I have decided that I will still buy the solar panel this year, and the duogen in a couple of years ( or maybe sooner if bank manager can be bribed)

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Ric
16-01-04, 18:57
Jerry,

I'm interested to hear some positive reports of your duogen, as lack of any independent recommendation was one thing that dissuaded me against them, the other being my scepticism of some of the design features. I'd be interested in other feedback - for example what mode do you mostly use it in? Have any of the air blades broken? How easy is it to switch modes at sea (as opposed to at anchor)? How well does the fan stay into the wind - given the relatively small aerodynamic moment of the fin?

You are right that putting the weight low down is an attractive feature of the design, as is the fact that the cost of the mast is included.

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JerryHawkins
19-01-04, 12:15
Hi Ric,

Blades seem pretty robust, certainly haven't broken one yet. I've never tried changing mode whilst under way, not sure when you'd need to; but it would be tricky as you'd be standing up on your transom in a fairly precarious position. To date I've mostly used wind mode whilst at anchor. Doesn't stay as firmly into wind as some other designs appear to. I've found that during gusty conditions it seems to turn out of the wind, possibly due to gyroscopic action, as a gust drops. Despite this, it manages to keep on top of my power requirements - fridge, instruments, tv and radio whilst at anchor with 14-16kts of wind.

The current air hub does not use the pin-drive of the water unit. I found this needed far too much maintenance to keep it running freely. My suggestion to Eclectic to use bevel gears was taken up and implemented! They are a very dynamic company and always willing to listen to suggestions from customers. My latest idea, which Pete Anderson is looking into, is the possibility of having adjustable pitch blades on the water unit to allow for the different speed capabilities of different yachts.

Cheers, Jerry

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Talbot
19-01-04, 18:48
Jerry,
thanks for your helpful data. Apparently the ali wind stabiliser will shortly be replaced by a fibreglass replacement. Whether this will be same size or shape is not known. I am hoping the design will stabilise soon!, however they do appear to be a company that responds to good suggestions.

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