Hydro generators

laika

laika

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Dodgy hydrogenerators seem to be in the news at the moment so I thought I'd ask about the current state of the market

I'm planning a not-so-little trip and considering power requirements. A while back I was looking at duogens and aquagens and being underwhelmed by the power produced at the 6-7kts Laika is likely to manage. I was briefly excited by the watt and sea hydrogenerators producing twice the output of what I'd previously seen but then discovered the out-of-ballpark €5k price tag. I've thought about wind/solar only: trade winds minus boat speed would still seem to be enough to provide more power from one of the newer rutland wind generators than I could get from a duogen in water mode (and far more than the duogen in wind mode). A gentleman from eclectic energy (who make duogen) argued that a wind generator would perform way below specs whilst under way due to boat movement and that water gens were the only reasonable answer while moving. Of course he would say that, but it seemed a reasonable argument.

So what is the most efficient water generation option currently for <~€2500 all in, or even for long passages am I better just investing in wind/solar? Given Laika's weight I'm not overly worried about drag.
 
Just acquired one of these second hand http://www.ampair.com/yacht-generators/aquair-100 . Not used it yet but if it matches the figures quoted it should be OK. Not as easy to move from water to wind as the duogen but seeing as I paid pence for it I'm not too worried. No idea what they cost new - ah, just found this on ebay http://www.ebay.co.uk/sch/i.html?_nkw=aquair+100&_sacat=0&_odkw=ampair&_osacat=0&_from=R40 at £1,250, so comes in a bit cheaper than the other alternatives.

Edit:
On re-reading the ebay post, it is only for the water option - you'd need to buy the wine turbine kit as well. No idea what that costs but still likely to be cheaper than the alternatives.
 
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duncan99210 said:
Just acquired one of these second hand http://www.ampair.com/yacht-generators/aquair-100 . Not used it yet but if it matches the figures quoted it should be OK.
Click to expand...

5amps at 6 kts, about 3amps at 5 kts and about 4 amps in wind mode with 20kts of wind (less than half what a rutland 914i would give?). Certainly sounds ok if you got it for a good price but I was hoping to find something to power everything (including autopilot), so at least 10amps@6kts.
 
I can't help thinking that the duogen/aquair type devices are rather "Heath Robinson" and probably messy to deploy/retrieve. With average trade wind speeds around 20kts, and apparent speeds probably somewhat lower most of the time, wind generators probably won't do too well. Had you thought about something like the Ampair UW100 turbine? This could be neatly mounted on a transom bracket and should generate about 7A at 6-7kts, and costs around $1000 I think.
 
Although I've had problems with my Duogen,due to damage in a knockdown,when deployed in water mode (5 mins max to change from wind) ,it does what it says on the tin. 6amps at 5knots. In wind mode I have no complaints,it is quieter than most. Downwind ,I don't think any wind powered genny is going to cut it.
 
I could be wrong but I believe the UW100 isn't designed as a yacht generator (they have the aquair 100 which duncan99210 mentioned for that) and if so I'd be faced with some dodgy fabrication (not my strong point) and the fact that it's probably not built with drag in mind (my comment about not being super-concerned with drag notwithstanding). I understand that generators on long bits of string tend to be bitten off.

In any case, I'm really wondering if there are affordable newer alternatives to these older generation products which could put me in the 10amps@6kts ballpark. The watt & sea units surpass that but are waaay too expensive. I notice that there are similar units from cristec which I can't find a price for and swi-tec which whilst half the price of the watt and sea is a bit flimsy looking for the considerable cost.

Anyone know anything about those or have other new generation alternatives to suggest?
 
This is not about water gens but

I'd not get too uptight about power usage when under way but look at the overall needs. We seem to use as much power at anchor as when on the move. At anchor we still run the watermaker, I suspect we open the fridge door more often, we use the computer/phone etc more often. So our power needs at anchor are still quite high. With this in mind you might want to re-think. Work out what you will need in terms of power at anchor and then when on passage. We have wind, solar and water. We tend to anchor in places with not too much wind - that's why we choose them. Conversely we do travel in the summer - when it can be sunny.

Again we find we spend more time at anchor than on passage and once we get 'somewhere', we potter around from bay to bay and there is no time to deploy a water gen (and often the engines are running anyway).

Having said that we use a LVM Aero-aqua gen (which they do not sell any more). traling log like thing on a rope. Best thing since sliced bread, if we are going on a long passage - a bit fiddly to convert if only a few hours. We have not had one eaten but have lost blades (on the traling log/impellor). Maybe eaten, but less romantic - might have hit a bit of wood (they are only GRP). I made new ones from stainless.

If you have the money, all three, if you do not have the space (and are to sail where there is not much sun) then solar is less of an option. Wind has its downsides, if trade wind route. But we like the water gen, but we travel faster than you indicate, maybe realistic average of 8 knots and if we have the choice and do not look to achieve the 8 knots - we'ed spend an extra day until we can. If we were crossing the Atlentic of Pacific, we would not want to go without a watergen.

I think there is another rule that your power consumption is always 20% higher than your ability to produce it without using your engine (or a gen set)

Sorry that I do not have an answer
 
I've got one of Rutland's 913 windmills. At sea it spends a lot of time spinning horizontally as the unit is quite heavy and has no damper to keep it under control and keep it pointing into the wind.

I've heard nothing but praise for the Duogen unit, at sea, besides being rather expensive.

Take all the manufacturer's data with a pinch of salt.
 
laika said:
I could be wrong but I believe the UW100 isn't designed as a yacht generator (they have the aquair 100 which duncan99210 mentioned for that) and if so I'd be faced with some dodgy fabrication (not my strong point) and the fact that it's probably not built with drag in mind (my comment about not being super-concerned with drag notwithstanding). I understand that generators on long bits of string tend to be bitten off.
Click to expand...

Maybe it isn't designed as a yacht generator, but the data sheet has a photo of one fitted on a simple tube on the transom of a boat. It has marginally more drag than the Aquair 100 (say 50-60lbs vs 40-50lbs). As it's designed for fairly permanent installations, it's likely to be more durable than the Aquair in service.
 
I have an Aquagen and am pleased with it. It does not produce as much amps as you want, but it is way cheaper than the watt&Sea or Duogen, takes up much less room at the back of the boat, is less unsightly, is easier to mount, and stabilises the boat when I am running downwind. I'm not concerned about it being bitten off. Dolphins are too intelligent to bite it, even Pilot whales don't seem that interested though I do pull it in if I see them, as they are sometimes a bit daft. It would take a truly massive shark to bit it clean off, and encounters with such beasts are rare.

You could get an Aquagen and then spend the money you save on a wind generator or more solar panels. I have all three on my boat - very satisfying watching my ammeters

 
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Thanks for the replies. I'll take from this that the forum's experience is that even an older water generator is more useful than a wind generator whilst moving. Many people will probably say I should invest in a wind vane rather than trying to power the autopilot..

I received a reply from cristec. The bad news is that the retail price will be (when it is released in March) only a little less than the watt and sea, retailing at €3895+VAT. On the upside the claim is for 150 watts at 5.5kts, 300watts at 6.6kts and a stonking 500 watts at 7.5 kts

Exactly what I want, but sadly I will have to wait for prices to come down quite dramatically
 
laika said:
I received a reply from cristec. The bad news is that the retail price will be (when it is released in March) only a little less than the watt and sea, retailing at €3895+VAT. On the upside the claim is for 150 watts at 5.5kts, 300watts at 6.6kts and a stonking 500 watts at 7.5 kts
Click to expand...

For that money, you could almost deck your boat out with enough solar panels to generate power by starlight :D
 
My early model Duogen has proved highly effective in water mode on both Channel and ocean trips for ten years. So much so that I am now replacing it with the latest model which has design improvements to improve durability (eg beefed up, carbon fibre reinforced drive shaft etc). I try to run an electrically efficient boat (interior and masthead lights are LED, no invertors, low-drain chart plotter, small radar, windvane steering), so this means that I can have everything running day and night on long passages. Regarding drag, we once tested this on my previous boat (Halmatic 30) by repeatedly launching and retrieving while sailing at 5 Kt in a light breeze. We were unable to detect any change in speed (log response in 0.1 Kt steps). On my current boat (Rustler 36) more momentum means drag is even less significant. Launching is easy, retrieval under way is easy enough up to 5 Kt boat speed, though above this I should prefer to retrieve it when hove-to.
 
If you are going on a long ocean passage your power usage can be cut quite dramatically - simply switch off the chartplotter and depth (not much point pinging away in 2,000m) - you really do not need them. All you really need is a log, distance and speed and a compass. You need to be fairly religous about filling out the paper log and then its simple DR. You will find that if the weather is benign you will look for meaningful things to do and you can keep the crew committed by running some form of competition.

You tend to feel a bit maked without a chartplotter - but who cares if you are out by 10nm in the middle of an ocean. You can always switch it on every 24 hours to check on accuracy of your DR.

LED nav (and interior) lights will save heaps, as will Broadband radar. The fridge is a fixed commodity (though you could beef up the insulation and maybe ensure the warm air from the compressor is led away (from the compressor) as quickly and as far as possible. Finding some way of feeding fresh air to the compressor fan will pay dividends (they are usually housed in an enclosed space with an apology for a vent). I'd worry about your land based, or close to land, consumption and as mentioned, for the money you quote you could pave the decks with solars.

But if you have the money - get a water gen.
 
I would look at 2 different options.

- Solar panels
- Shaft driven generator. Amel has this option on their vessels. A mate powers all his electrical needs from the shaft generator when he equals or exceeds 6 knots. (Autopilot, all navigation kit, 2 freezers and a refrigerator)

Worth considering if you can mount one correctly on your shaft.

GL
 
I sailed more than 10,000nm with an aquair 100, it constantly produced enough to run all on board requirements and we had no LED lighting. Lap top, ssb receiver, printer lights (all night)

there are two turbines for slow and fast which were worth having, deploying and retrieving is not a problem and we only had one shark bight, scratched the enamel and probably damaged his teeth.
 
Update. With the current state of the euro I thought I'd revisit this. Turns out that the Cristec has been pulled from the market: something to do with a design patent infringement I think. This leaves (that I know of) two "cruising" versions of the Watt&Sea and the SWI-tec:
http://www.wattandsea.com/en/cruising-hydrogenerator
http://www.swi-tec.com/shop/hydro_charger?gclid=CIHs7IviicUCFerjwgodMVcAGQ
The latter may have been re-designed but when I saw it a couple of years ago it looked a bit flimsy (certainly less "quality" than the now-defunct cristec). Still with the current exchange rate looks like a similar price to the duogen for a significantly more useful power output (but obviously no "wind mode"). The power curves in the Watt&Sea url above appear to be for the more expensive "600" model. The "300" is a similar price to the swi-tec (maybe slightly more) but for less power.

Anyone here using a hydrogenerator now? I'm seriously considering flogging my diesel generator to fund buying one as an alternative (in conjunction with autopilot) to a wind vane.
 
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