Wind Generation vs solar panels

[Neeves]

Most here would not consider wind generation, at all. ITT bought LVM (aka Aerogen) transferred production to China and then closed it all down, presumably because they could not generate sufficient sales. Anecdotally it was said they tried to sell the business and had no takers. Yet at almost the same time a German start up was developing and releasing an updated version of the wind gen. They are now claiming interesting sales numbers (though glancing through the website - no mention of yachts nor marine applications - but I only skimmed through).

Product | SkyWind Energy Inc.

The sales are even more interesting when you consider the price - its not cheap.

I'm sitting at breakfast, there is a brilliant blue sky...... and no, or little, wind.

As a complete aside I have been quoted US $0.15/wp for container loads of 500w solar panels, standard framed panels ex China. I assume a 500w panel is a fairly standard size for a domestic or even large scale array. I further assuming panels for 'our' size are smaller and cost more. I shudder to think how many panels you need to buy to fill a container.

I always rated our Aerogen as it did work 24/7 and often when there was little sun there was wind. However in terms of output it generated more than enough in hydro mode, with a trailing impeller - but of course you did need to be sailing - then a WattnSea enters the equation (also not cheap)

Jonathan.

 

[Caladh]

Wouldn’t have been without my trusty Aerogen6 in the Med for 10 years or so

 

[William_H]

Well the good news is that yachties have a choice or can go with both. However I think most would go for solar. So much depends on various factors. So we very seldom see a yacht with wind gen here in oz. Plenty of sun. High latitudes would mean less sun so wind gen more practical. Then with solar there is concern re finding place to mount large array. Obviously not a concern for remote house power.

Incidentally when I was kid (70years ago) it was not uncommon in country areas to see a post with a turbine (actually more like a 2 blade propeller) driving a dynamo for a 32 volt power system. (mains power did not extend far into the bush until 1960s) No solar PV then.

I have always advocated sailors consider those domestic/industrial PV panels as being cheapest and now more efficient although producing 40v or more so demanding MPPT controller for 12v system. Unfortunately they are big, being sized I think for one man to manage when installing. But the volume sold makes them very cheap. Perth (2milion people) have something like 50% roof top solar. That is already a lot of panels typically 12 per house already sold. Extrapolate that around the world.
In the end a sailor will choose what he fancies but small solar is so easy to fit to get some power. But then the good old alternator on the engine can do a lot of charge. ol'will

 

[NormanS]

When we bought our new to us boat, she had a wind generator which didn't work. I repaired it, and got it working. It had a huge disadvantage of being difficult to access, being well up on the mizzen mast. Although the controller was supposed to slow it down in severe winds, sometimes the wind was too strong, and eventually, in a very frightening episode, when I can only assume that it lost a blade, it disintegrated. Fortunately most of it went clear over the side, although an unknown heavy fragment seriously damaged the stainless taffrail.
When the wind generator worked, provided there was more than 10 knots of wind, it gave a useful output at anchor. It was useless when sailing, and just used to rotate on its spindle. It wasn't particularly noisy, but being installed on the mizzen mast, it was directly above our aft cabin, and so even it's modest noise was transmitted straight down the mast into the cabin.
Our sailing is now only in the better six months of the year, and being in a relatively high latitude, we have a lot of daylight, which PV panels need.
At present we have 180w of panels, shortly to be increased by another 100w. They are wonderful, totally silent, no moving parts, cheap, and simple to maintain.
If I was ever thinking of going back to wind power, it would have to be installed on a dedicated pole, so that it was simple to physically tie it off for safety.
For me, PV panels are the way to go. We have them on the roof of our house, and being early in fitting them, we benefit from a very generous feed in tariff.

 

[Rappey]

Location is key to the efficiency of a wind turbine. Wind can produce more power than solar during a British winter plus your wind turbine keeps working during the night.
Solar is easy to fit, wind needs a pole and supports which can set you back another £300+.
I like having both.

 

[B27]

Get the graph of power out vs wind speed for the wind generator you're interested in.
Measure the wind speed where you might mount it.

If you've got a hand held anemometer, you will soon see that most places you'd care to keep your boat often have quite a low wind speed measured at say 10ft off the water instead of at the masthead.

Then you can make a more useful guess of how much power you'll get, how often etc etc.
Then you can think about how valuable that power is to you.

Some commercial users are happy to pay a lot for a small amount of power, because e.g. collecting data can be very valuable. Others are putting in sizeable turbines to get moderate amounts of power.

Unless you are going to put numbers to it for a particular set of circumstances, it's just waffle really.

 

[noelex]

Most here would not consider wind generation, at all. ITT bought LVM (aka Aerogen) transferred production to China and then closed it all down, presumably because they could not generate sufficient sales. Anecdotally it was said they tried to sell the business and had no takers. Yet at almost the same time a German start up was developing and releasing an updated version of the wind gen. They are now claiming interesting sales numbers (though glancing through the website - no mention of yachts nor marine applications - but I only skimmed through).

Product | SkyWind Energy Inc.

The sales are even more interesting when you consider the price - its not cheap.

Jonathan.

That wind generator looks to be designed for domestic/industrial use, rather than something that may be fitted to a yacht. The blade diameter at over 1.5m (almost 5 feet) is larger than most yachts could reasonably consider. If you are really looking at a wind generator for a yacht rather than a house, there are better choices.

Wind generators are a useful alternative source of power on a yacht, but they are difficult to install where they do not cause some shading on solar panels. It is important to factor in any loss of solar output when estimating how much useful output they contribute.

 

[michael_w]

After my experience with a POS Rutland I wouldn't have one again. Fibs about its output, didn't work when the boat heeled, Poorly engineered mast, so it tried to commit suicide several times. Oh, and it burnt out once and ate 3 controllers.

 

[Stemar]

An engineer friend looked into this when thinking about how to get more power on board. He took the output/windspeed curve for a Rutland wind gen, and compared it with the output/insolation curve for equivalent solar panels (can't remember how he got an equivalence - maybe cost) for the southern UK, as that's where he lives. Solar won comfortably.

Yes, there are grey days in winter when my panels give me next to nothing, but there are also windless days. Solar panels also have the advantage of silence.

 

[MontyMariner]

Solar don't work at night, but are fairly consistent o/p in daylight, low maintenance and not too expensive to replace.
WG's don't work at low to no wind, pretty much useless when running downwind, expensive to buy and need costly maintenance plus some people don't like the noise they produce.
I ditched my WG after about 18 years use, after a few sets of bearings and some uprated rectifier diodes, when it needed new (expensive) blades. I now just use solar.

 

[Neeves]

That wind generator looks to be designed for domestic/industrial use, rather than something that may be fitted to a yacht. The blade diameter at over 1.5m (almost 5 feet) is larger than most yachts could reasonably consider. If you are really looking at a wind generator for a yacht rather than a house, there are better choices.

Wind generators are a useful alternative source of power on a yacht, but they are difficult to install where they do not cause some shading on solar panels. It is important to factor in any loss of solar output when estimating how much useful output they contribute.

It is relatively easy, actually very easy (but then we did it) to have a cranked mast on the transom, where the blades are all aft and the whole structure is well out of the way. The mast for the fan can easily be braced. The advantage of the transom is that it does not shade anywhere and as the boom, when sailing is nearly always offset then the centrally located fan enjoys all the wind off the main. You can see our wind gen located on the transom well aft, its located above the height of the cabin roof and is braced with 2 dyneema stays to the ends of the davits. Since this picture was taken we upgraded our solar. You could make an almost indentical installation on most yachts. It was a windless day - and sunny but still enjoying some shade.


It would be interesting to know what your 'better' choices are for wind and your experiences in using wind generators.

We had the LVM aero4aqua gen and wish we had bought the aero6 (bigger fan). The aero4 was not noisy. The alternative, in part, to a wind gen is a petrol or diesel generator - most I know of are hardly described as quiet. We were so impressed we did think of buying a second wind gen - but LVM went belly up before we committed.

Our view, from sunny Australia, was that if you want to have energy 365 you cannot rely on solar alone. You simply cannot have a large enough solar display and battery bank - even on a 38' cat - to be self sufficient, live in the 21st Century and cater for 3 or 4 days of overcast skies. Lithium may have changed that, it came too late for us - but...... With lead you needed alternative sources of power as the usable 200amps from a 400amp bank was simply not enough. Wind is possibly the best developed. We did hanker after the WattnSea.

Jonathan

 

[noelex]

Our view, from sunny Australia, was that if you want to have energy 365 you cannot rely on solar alone. You simply cannot have a large enough solar display and battery bank - even on a 38' cat - to be self sufficient, live in the 21st Century and cater for 3 or 4 days of overcast skies.

That has not been my experience.

 

[Gsailor]

There are different makes of wind generators - some are better than others.

I also owned the type that could be used to tow a propellor.

Solar is excellent - pretty much always- but with a full compliment of solar panels and two wind turbines you are going to be ok for sure - and I like for sure over “perhaps”.

I have always been able to service my own wind turbines fortunately - last count I had 4 I think (and one is still in its box from new - did not get around to fitting it even after fabricating a special bracket for it) - I was going to fit it to the eves of the house to give decent garden night lights that lasted ALL night (and lots of them) and power a vhf listening (only) radio - and perhaps have a few joules left over to charge mobiles etc (they take a fair bit of energy for their size you know).

I like free electricity and don’t mind getting greasy and playing with magnets, brushes, controllers...

 

[Neeves]

That has not been my experience.

I'll challenge you, define your usage, including desal, electric cooking, running the marine systems, fridge, deep freeze, hot water for showers.

How many solar panels do you need, what capacity? Recall Australia covers from the chilly south to the tropics and I suggested 365.

No data? - just talk? and talk is cheap.

Frankly if you want to remain in the 21st Century - its difficult to rely on solar (unless you have a very larger vessel with lots of room for solar (harvesting both good and bad days) - without making sacrifices (like disowning the grand daughters - and that is not an option, hot showers are a birthright).

Basically if you take any responsibility for grandchildren you need to be near fresh water - as de sal is a massive user of amps - even just the 2 of us - SW Tasmania (which is truly off grid) is a real challenge .

So ..... let's see the numbers

There are enough members here who live off grid - I am sure they will be interested in your reply - but take your time. It will be educating for us all and I for one will be happy to see what size of a solar display you need covering 44 degrees south to the, almost, equator, 365 and no recourse to 'camping'.

Jonathan

 

[NormanS]

I'll challenge you, define your usage, including desal, electric cooking, running the marine systems, fridge, deep freeze, hot water for showers.

How many solar panels do you need, what capacity? Recall Australia covers from the chilly south to the tropics and I suggested 365.

No data? - just talk? and talk is cheap.

Frankly if you want to remain in the 21st Century - its difficult to rely on solar (unless you have a very larger vessel with lots of room for solar (harvesting both good and bad days) - without making sacrifices (like disowning the grand daughters - and that is not an option, hot showers are a birthright).

Basically if you take any responsibility for grandchildren you need to be near fresh water - as de sal is a massive user of amps - even just the 2 of us - SW Tasmania (which is truly off grid) is a real challenge .

So ..... let's see the numbers

There are enough members here who live off grid - I am sure they will be interested in your reply - but take your time. It will be educating for us all and I for one will be happy to see what size of a solar display you need covering 44 degrees south to the, almost, equator, 365 and no recourse to 'camping'.

Jonathan

You're coming over really grumpy today.
The guy's not arguing with you. He just said that his experience was different. Maybe he doesn't have demanding grandchildren.

 

[Neeves]

Me, grumpy?

I just like being proved wrong - its part of the learning process, learning from your mistakes.

I did like your description of experiences with a wind gen. We have a friend with a rather large (and now getting old) yacht. He bought it from someone who did the ARC and got tired of the life after he had reached Australia (but I digress)

It had a wind gen and one of the crew let go of the main halyard and the shackle hit the wind gen and destroyed one of the blades. Not able to get a replacement he removed the complete device.

You are not alone.

One of our grand daughters opted for an engineering degree - I wondered if it would end in tears. I need not have worried - she was on the team that took part in an annual race of solar cars and Sydney Uni won the race, from Darwen to Adelaide. She will be co-opted to my team on my portable Lithium power pack..... Funny how life works out. I'm the one who is demanding

Jonathan

 

[bergie]

We have 660W of solar on our 31ft boat (360W fixed, and another 300W of FLINsail that we deploy to the mast when anchored). With that we’ve been more or less autonomous during the Baltic Sea summer. We consume around 1.3kWh per day - a bit more when we run the diesel heater.

However, to be on the safe side, we wanted a second renewables source to cover for the longer periods of overcast skies. The battery bank can carry us for roughly three days without any energy input (as it has to do when we’re winter anchoring), but that still needs to be topped up somehow. To make the decision on wind vs. hydro I ran some simulations based on the actual sensor data we had gathered during our five month Baltic cruise in 2022.

For us, there was a slight edge for a wind generator (the green bar in graph below) over a hydrogenerator, but we still ended up going with the hydro. Two reasons for this: First of all, hydrogenerator was easier to fit on our double ender. Secondly, we decided that instead of incentivising anchoring in windy spots, we’d rather incentivise going sailing more.

You can see the calculations in Wind vs water

 

[ghostlymoron2]

We've got solar at home and, although they generate on cloudy days its 200w against 3-5kw when the suns out.

 

[noelex]

Australia has very good solar insolation. Even Tasmania at a latitude of 44° degrees is not a long way from the equator compared to many cruising grounds. For example, the Shetland Islands are around 60° N as is most of Norway. We have cruised these areas generating virtually all our electrical power via solar, so it is possible. The exception was Scotland in winter (but few cruise Scotland or even Tasmania during winter). This has been the only time we occasionally needed some supplemental charging (via a high output alternator).

We cruise full time, averaging over 300 days a year at anchor and have done so for the last 17 years. We currently have a 49 foot monohull with just over a 1000w of rigid solar panels and a 600Ahrs @24v battery bank. As we cruise full time, we have all the "essential " electrical luxuries you mention (fridge, freezer, watermaker) plus a washing machine. In areas of reasonable solar insolation we do all electric cooking, and use electric heating for shower water. In areas of poor solar insolation we switch over partially or wholly to a combination propane and diesel for these functions. We do not have a generator.

Designing a self sufficient electrical system is complex, but it would have certainly been possible to update your catamaran’s electrical system to achieve this goal with solar alone when cruising any part of Australia and without skipping any of your requirements. The photos you have posted show only a minimal amount of solar (and much of this in shade prone locations), but you have indicated this was subsequently increased. How much solar did it have when you sold it?

One important element often overlooked is installing electrically efficient appliances. For example, you mention:

- as de sal is a massive user of amps - even just the 2 of us - SW Tasmania (which is truly off grid) is a real challenge .

Jonathan

This need not be the case. If relying on solar you really need to fit an energy recovery watermaker unless you have a large catamaran with loads of room for solar. These watermakers use a fraction of the energy. A rainwater collection system is also a big help. We installed a rainwater collection system primary as backup in the event of watermaker failure, but in climates like Scotland it provided us with all the water we could use without any electrical consumption.

The bottom line is that if you ever buy another 38 foot catamaran in Australia and want to run all your electrical systems from solar this is not difficult goal to achieve.

 

[B27]

We have 660W of solar on our 31ft boat (360W fixed, and another 300W of FLINsail that we deploy to the mast when anchored). With that we’ve been more or less autonomous during the Baltic Sea summer. We consume around 1.3kWh per day - a bit more when we run the diesel heater.

However, to be on the safe side, we wanted a second renewables source to cover for the longer periods of overcast skies. The battery bank can carry us for roughly three days without any energy input (as it has to do when we’re winter anchoring), but that still needs to be topped up somehow. To make the decision on wind vs. hydro I ran some simulations based on the actual sensor data we had gathered during our five month Baltic cruise in 2022.

For us, there was a slight edge for a wind generator (the green bar in graph below) over a hydrogenerator, but we still ended up going with the hydro. Two reasons for this: First of all, hydrogenerator was easier to fit on our double ender. Secondly, we decided that instead of incentivising anchoring in windy spots, we’d rather incentivise going sailing more.

You can see the calculations in Wind vs water
View attachment 166872

I think the link says the wind generator should give 25Wh per 24h, or less, on over 90+% of days?
That's for a mix of sailing and non-sailing days?

Which is maybe useful for keeping some batteries on float charge, maybe a few hours of reading lights. Maybe run your nav lights one night a week? In the 70s it was enough to run a radio receiver at pre-arranged hours and keep the battery charged in case you wanted to transmit. A little bit of power is very valuable when it's all you've got.