Are Wind Generators even worth it?

[hanami2]

Originally Posted by sparrowhawk1

It would be cool if someone could do a cost analysis of producing 100 to 200 amp hours a day comparing a generator to solar panels and wind. my money's on the solar panels and wind. And if you include having to haul fuel to your boat on a weekly basis your time should be worth something

Producing electricty on board is always a a tricky question.
My guess is that each sailor you go to will give a different answser depending on their past experience.
I am not doing to write my own 'book of the truth' but give you some feed back after a coulpe of transatlantic trips (back and forth 2 times).

The boats is equiped with:

• 2 100 W solar panels
• 1 D400 wind turbine
• 1 Watt&Sea hydrogenerator (W&S)
• 1 2800 W power generator

• Sailing west bound and mainly down wind from Europe to the Carribeans the wind turbine doesn't deliver a lot if you have less than 20 knots of wind.
• On the way back, that's different as you have more windward opportunities.
• On both legs the Watt&Sea will deliver almost 18 Ah once you are past 6 knots of speed and past 7 you have more 'than you can chew'.
• In the Caribbeans with steady 20N of wind at anchor the wind turbine is OK and the solar pannels deliver correctly if they are properly oriented toward the sun and not in the shade of anything. Of course the W&S is useless if you are not sailing but will top-up the batteris nicely when sailing even for short distances if you can get speed.
• At anchor the Solar PAnels AND the wind-turbine will be OK for a couple of days but past this you will have to sail or run the engine or the generator if you use a lot of electricty.
• We did use the generator for having hot water for showers, when running the water maker or the bread cooker.
• Except for thos last cases the boat was self-sufficent without any need for generating electricity from fuel.

I hope it helps but it all depend how much energy you need.


Marc.

[neelie]

Originally Posted by barnakiel

What happened to the initial cost of the generator then?

b.

Good Question!.

In our case it got lost in my "sub-prime" accounting practice largely because it came with the boat. That leaves running cost as the only variable for me.

But, certainly, if you were building a boat from scratch, then of course generator purchase costs must be included and the balance tips the other way.

[mbianka]

Originally Posted by Canibul

I've got 850 watts of solar, if we're going by the max wattage listed on the solar panel labels. 2x65 and 6x120. So if I fixed or replaced the 'supposedly' 400 watt wind gen, I could make an electric boat? Cool. A trolling motor for a 40 ft. cat..

Yeah you could if you panels are providing max power and your wind turbine is cranking. But, that does not happen 100% of the time. Probably much less than 50% of the time. A pure solar play with electric propulsion is tough at this point but, you are close. My 8 ton 30 foot monohull moves along nicely at 3 knots using 900 watts. But, I only have 120 watts of solar available. But, don't forget your sails are an energy source too! So even if there is a little breeze the amp load on the EP system decreases dramatically as the wind picks up. At some point on my system it starts to regen back and recharge the battery bank. It's not a lot at first but, over several hours it does add up. With solar panels and a wind turbine helping it all helps to refill the fuel/energy bucket!

[Canibul]

I love the idea of it. Really. So does my wife. We've got two antique and discontinued little diesels in the boat that I'm going to have to deal with some day. We're coastal cruisers and have no interest in crossing the Pacific in a sailboat. We live in a place with almost constant sun and wind. The idea of two electric motors is appealing, although I'd want a little diesel gen-set that could get me home in the dark if I needed it.

But we do need TWO motors. I suspect that changes a lot of things. The upside is we have tons of real estate for more solar and could also easily fit two wind gens.

[mbianka]

Originally Posted by Canibul

I love the idea of it. Really. So does my wife. We've got two antique and discontinued little diesels in the boat that I'm going to have to deal with some day. We're coastal cruisers and have no interest in crossing the Pacific in a sailboat. We live in a place with almost constant sun and wind. The idea of two electric motors is appealing, although I'd want a little diesel gen-set that could get me home in the dark if I needed it.

But we do need TWO motors. I suspect that changes a lot of things. The upside is we have tons of real estate for more solar and could also easily fit two wind gens.

Sounds ideal for EP. Though I would never advise anyone to take out a good running diesel but, when they die (as mine did) at least take a look at EP. Having two motors should not affect things except you will have a lot less maintenance compared with the two diesels. Even one diesel genset would be easier to maintain in a convenient location than the two diesels connected to the prop.

[Littlechay]

Originally Posted by sparrowhawk1

And if you include having to haul fuel to your boat on a weekly basis your time should be worth something

Your fuel tank would have to be ridiculously small to have to haul fuel on a weekly basis for that amount of juice!

If your running your engine or a generator to charge the batteries you should have your bank sized so that, in your case, 200 AH is 30% of your banks capacity ..... so you want a bank that is about 700Ah.. then you start charging at about 50% discharged and run the engine until the bank is up to about 80% when the battery acceptance rate drops off.

If you have AGM batteries you could probably stuff about 100A in - so two hours running . A little genny isn't going to burn that much fuel for a couple of hours a day.

A 2.5kW generator, one of those fancy inverter ones if you like - a 20 litre can of fuel is going to last, what? 3 weeks.... not bad.

Definitely the best bang for the buck... but it's not all about bucks is it!

Now that is just to illustrate a point ... running a generator for two hours a day is way too much dicking around for me.

So then back to wind and solar topped off by the engine when motoring it is then.. and I have flooded lead acids so I have to dick around and equalise them every now and again, but nothing if for free; it's all about the compromises that suite your lifestyle and cruising needs.

[sparrowhawk1]

Littlechay. Okay so every 3 weeks instead of once a week. And like you said having to hear the engine run and having to be there everyday to bring your batteries up to 80 percent and every once in awhile to 100%. having to have a larger battery bank ( and maybe gel instead of the less expensive standard LA). Having to do maintenance. all puts the solar and wind ahead of the generator imho . I have solar, wind a Honda 2000 and an alternator on my diesel axillary but I try never to run my engines to charge my battery.( I like to run my engines once a month for maintenance and try to coincide it with cloudy days) I know what works for me. I just think it would be really cool to see it broken down on paper. And it will help people trying to make the decision on how to charge their batteries. Edit: And if your generator is something like a Honda you also have to purchase a high output battery charger

[Littlechay]

Originally Posted by sparrowhawk1

having to be there everyday

Sorry I thought we were talking live aboard cruising here...

On your other point - you have to do maintenance on 'any' system, even solar panels need cleaning, but yes some are more onerous than others, and it depends on the individuals skill set too... for example somebody who doesn't know a spanner from a screwdriver should probably install solar (errr have solar installed for them).

When I get time I'll knock up a spreadsheet based on some of the setups that people have described here.... or you could do it as all the information is here; I'm about to go sailing

[Littlechay]

Originally Posted by hanami2

The boats is equiped with:

• 2 100 W solar panels
• 1 D400 wind turbine
• 1 Watt&Sea hydrogenerator (W&S)
• 1 2800 W power generator

[LIST]

Lets use your list for some cost analysis; but first we need a more complete picture.

What is your battery bank, battery type, size and chemistry?
What charge controllers are you using on the wind, solar, hydro?
What battery charger are you using in conjunction with the 2.8kW generator?
What alternator(s) and alternator controller(s) are you using on the engine?
What is your average passage speed?

That should be enough to get into the ballpark with production

But we need some power consumption figures too, and average daily Ah consumption for day, and for night would be useful.

Chris

[The Smokester]

From Charlie Wing's "Electrical Handbook", he calculates the Cost of Electricity to recharge a 50% discharged 440 Ah battery bank based on 10 years of use. Using Utility Power: few $0.10's / kWh; Solar: $0.42 / kWh; Wind: $0.59 / kWh; Diesel Engine using 110 amp alternator: $2.30 / kWh.

[Cheechako]

Originally Posted by Canibul

How many gallons of fuel could you have bought for what that electric setup cost you, though? Hasn't that been the problem with solar since the beginning? we never recoup the energy costs that went into producing the equipment.

That's where my mind goes when contemplating what is best; panels, wires framework, windage... all that stuff hanging off the boat. Some cruising boats look more like a cell tower array! Running the diesel is actually good for it... and cheap and simple. Too many diesel aren't run enough. The truckers run them constantly and get half a million miles out of them.
Not really nixing solar.. I love the concept.. but.... sometimes simple just feels good. Of course if you leave the boat on a trip for a few days..the diesel wont charge!

[Littlechay]

Originally Posted by Cheechako

Running the diesel is actually good for it...

Depends on the load. Idling a diesel without much load is an engine killer. So if you are motor sailing or motoring then I agree, but using your propulsion engine as a battery charger is crazy.

[Canibul]

Originally Posted by The Smokester

From Charlie Wing's "Electrical Handbook", he calculates the Cost of Electricity to recharge a 50% discharged 440 Ah battery bank based on 10 years of use. Using Utility Power: few $0.10's / kWh; Solar: $0.42 / kWh; Wind: $0.59 / kWh; Diesel Engine using 110 amp alternator: $2.30 / kWh.

Interesting stuff, thanks. I assume those numbers were referenced to some fuel prices at the time of publication, and would vary but the relationship is what's interesting.

We pay $0.50/kwh here for utility power.

[Randyonr3]

for the last 8 years , we've been "OFF THE GRID" so to speak .. my solar and wind have kep the batteries fully charged.. Fact is I've been toying with the idea of replacing the alternator with an engine driven watermaker in its place..

[hanami2]

Originally Posted by Littlechay

Lets use your list for some cost analysis; but first we need a more complete picture.

What is your battery bank, battery type, size and chemistry?
What charge controllers are you using on the wind, solar, hydro?
What battery charger are you using in conjunction with the 2.8kW generator?
What alternator(s) and alternator controller(s) are you using on the engine?
What is your average passage speed?

That should be enough to get into the ballpark with production

But we need some power consumption figures too, and average daily Ah consumption for day, and for night would be useful.

Chris

Hi,

Here are the answers:

• Batteries 800Ah Pb-Ca (700 + 100, The Bow Thruster bank is not included).
• Charge controller is MasterVolt, same as all the electrical equipement that include the following: an Isolation Transformer, a 3000W MasterVolt Charger/COnverter for the house bank, an independant MasterVolt Charger for the Engine Bank, 2 Mastervolt alternators: one for the Engine Bank and one for the House bank (plus a spare one, just in case). The whole system is controlled by a MasterEasy-MasterView system connected to a PC for easier management.. A separate batteries bank is dedicated to the bow-thruster and is linked to the house bank.
• The windturbine has its own regulatoer, provided with the Turbine.
• The Solar Panels and the W&S have MasterVolt monitoring devices.
• The power generator deliver its energy between the Isolation Transformer and the Charger/Converter: it is seen as a shore power and deliver only 220V.
• Average passage speed is 6 knots for the full atlantic crossing.

Does this answer your questions?
Thanks for the comment.

Marc.