Solar v Wind

[LadyInBed]

Wind is better while using the boat. Solar better if left for longer periods.

Except when faces with 4 days of light downwind sailing, my 913 hardly turned!
Wished I also had solar, luckily I had a mains gen (I had engine problems so couldn't use it to charge batteries).

Re noise, my 913 has been spinning for 12 years (must get round to changing the bearings) it is sited up the mizzen directly above where I sleep and has never had any resonance problems, but a satisfying woosh in high winds which isn't an issue, as the wind itself causes more noise.

 

[NormanS]

That's interesting and I am getting the impression that 913 success depends on the regulator design, would you say that the heat sink is too small, thus resorting to hyperdrive sooner than might be neccessary?
I'm hopefully getting a 913 in a few days and I would be prepared for a regulator project or modification.
I wonder if any electronic whizz-kids have made a bullet-proof design?

(chargewise, I'm hoping to keep up with a clunky old Webasto heater and ipad charging while living aboard in winter in UK)
Personally am really excited to be getting free leccy from the wind, and I am ready for bearing replacement and regulator modification to get it right. I also sleep best with the sound of machinery running so am lucky in that respect!

Good to hear positive stories about the 913 as I have been offered one, cheers Jerry

I would suggest that you contact Marlec, the makers of the 913, re the best regulator. They are extremely helpful.
To be fair, the time when it goes into hyperdrive is usually if motoring into the wind (deep shame), the alternator is charging, and so is the windmill.

 

[jerrytug]

I would suggest that you contact Marlec, the makers of the 913, re the best regulator. They are extremely helpful.
To be fair, the time when it goes into hyperdrive is usually if motoring into the wind (deep shame), the alternator is charging, and so is the windmill.

Yes I will thanks. Personally I always use a bit of engine going against the wind, but I'm past caring..

 

[doug748]

Just wanted to make a response re noise- some wind generaters are noisy - but our Aerogen4 is so quiet that often we look up to see if it is actually spinning at all- and it is- no noise, no vibration, although it did whoosh at about 50knots. Good power generation at 18 knots and above. Had one for probably 15 years, easy installation 'fit and forget'. always on.

I second that comment about Aerogen. Shame the new owners seem to have lost interest in the product.

Mine has revolved almost continually for 20 years.

 

[oldvarnish]

Some interesting stuff has emerged in this thread.

BUT, as I've said before, a debate about wind versus solar gets you nowhere because you're not comparing like with like.

It's like trying to argue sails versus engine. There are simply occasions when one is better and more efficient than the other, and that can change quite quickly.

 

[Mistroma]

I agree with a lot of comments about having more than one power source and that lack of space for solar is a problem. Output from solar and wind will change with variations in the weather and wind can easily beat solar on some days. However, I've found such days to be fairly far apart and I prefer to consider the average performance rather than the peak output.

I made detailed records whilst sailing between Coruna & Porto this year. Most of the time was spent in the Rias. It is a little more detailed than just saying I got X from solar and Y from wind. gen. I don't know if this information will be of use to anyone but have put in a summary below.


Installation:
Solar: 145W (65W + 2 x 40W rigid panels) mounted on deck underneath the boom, but can be moved if required
Wind: Rutland 913 on standard pole supplied by Marlec (probably around 3m above sea-level)
Regulator: Marlec HRDi
Wiring for everything was quite heavy and so Voltage drop will be minimal for 913 & panels.

The table below shows average Ah/day from solar and wind for each month

Month____Solar_____Wind_____Total
May________59_______13_______72
June_______50_______16_______66
July________53_______13_______66
August_____49_______13_______62
September__41_______10_______51

Wind gen: Average 13 Ah/day (~10 Ah/day is normal for April - Oct. in prev. years)
The difference between max. & min. is quite large.
I did get a 110Ah/day for a couple of days but also got a lot of 0-5 Ah/day readings as well.
I did tie up the wind-gen for a couple of days in a marina. It was reasonably windy and there was a piling next to the Rutland. If wind of 30kn+ forecast I'd either be in a marina or very sheltered anchorage (I don't that this behaviour is too unusual).

Solar: Average 50 Ah/day
Variation between max. & min. was around 15-90 Ah/day
I didn't bother with solar if I was on shorepower in a marina. So it was just a matter of whether direction of the pontoon caused the panels to be shaded or not. If I was anchored for several days then I did usually move the panels to face the sun with as little shading as possible (this usually made big difference).


Conclusion:
On this basis, a 40W panel costing around £60-£70 would equal the average performance of a Rutland 913 between May-September. It wouldn't match the max. charge when anchored in a strong winds. However, it would easily outperform the Rutland almost every other day (>70% of the summer in fact).

Previous experience with the 913 confirms that ~10Ah average between April - October is normal for my boat when sailing around West coast of Scotland. Previous calcs. for solar indicated that performance in Scotland would vary between 66% - 80% of the average in Galica during the summer. I can re-visit my calcs. for predictions wrt Galicia and Scotland if more detail is needed.

I can post the raw data if anyone is interested. However, I'd like to clean it up first in order to mark days in marina on shorepower, any days 913 tied up etc.)

 

[KellysEye]

Rutland are known for a relatively low power output compared to (say) Ampair, hence the poor performance against solar:

Ampair wind knots Watts Amps
12 50 4.2
20 150 12.5
28 200 16.7

Rutland wind knots
10 3.0
21.5 29
29 49

Details of the full wind speed/output curves are here;

http://www.ampair.com/wind-turbines/ampair-300#technical On the Ampair site scroll down and click on 'full specifications'.

http://www.marlec.co.uk/products/windchargers/rutland-504-windcharger/

 

[Graham_Wright]

It's more an matter of how to find a decent location to put in panels able to keep up with daily usage. Rigid panels are pretty cheap but most people struggle to find enough space. The much more expensive wind-gen. provides a little extra power fairly regularly with the odd rare day where it actually keeps up with demand.

I have seen several boats with panels as the dodgers. They can be angled optimally (manually), and left horizontal when the boat is unmanned but would they be more vulnerable to water damage?

 

[stevebrassett]

Rutland wind generators should not be tied off for any length of time. They are designed to throw the water off the bearings when spinning, and the bearings get ruined quickly if the blades cannot rotate. I learnt the hard way.

 

[geem]

I have seen several boats with panels as the dodgers. They can be angled optimally (manually), and left horizontal when the boat is unmanned but would they be more vulnerable to water damage?

I have four panels located like this on my 44ft boat. The efficieny of this set up is far superior to flat panels on deck. I have 160w installed on the guardwires in this way. The angle can be adjusted and they are used whilst sailing like this. I have used panels like this 10 years with no issue of water damage

 

[JohnGC]

I have four panels located like this on my 44ft boat. The efficieny of this set up is far superior to flat panels on deck. I have 160w installed on the guardwires in this way. The angle can be adjusted and they are used whilst sailing like this. I have used panels like this 10 years with no issue of water damage

Can you post a picture please? I'm interested in mounting methods.

 

[Mistroma]

Rutland are known for a relatively low power output compared to (say) Ampair, hence the poor performance against solar:

Ampair wind knots Watts Amps
12 50 4.2
20 150 12.5
28 200 16.7

Rutland wind knots
10 3.0
21.5 29
29 49

Details of the full wind speed/output curves are here;

http://www.ampair.com/wind-turbines/ampair-300#technical On the Ampair site scroll down and click on 'full specifications'.

http://www.marlec.co.uk/products/windchargers/rutland-504-windcharger/

The links and figures indicate that you are comparing the Rutland 504 with the Ampair 300. Not much of a surprise. I once had a TVR which outperformed a Fiat 500 on acceleration and that didn't come as a great shock. I believe that the basic Rutland 504 sells for around £350 whilst the Ampair 300 is around £1,600.

It would be fairer to compare the Rutland 913 at £600 with the Ampair 100 at £880. I haven't carried out a test but think it would be fair to expect approx. 30% more from an Ampair 100 over the season vs. a Rutland 913.

Even if it managed to average 2 x output (highly unlikely), it would only result in:

Daily average
Solar 145W panels: 50Ah cost (£200)
Ampair 100: 14Ah (£880)

Mounting costs were ignored, but were higher for the wind gen.

There are many variables in wind vs. solar and my earlier measurements only relate to my own experience. However, it isn't surprising that solar wins out once you start digging into the physics. Don't expect PV panel or wind gen. efficiency to double as there are theoretical and technical limits.

 

[geem]

method of attaching solar to guardwires.

 

[JohnGC]

method of attaching solar to guardwires.

Thanks, that looks simple enough. Have you had any problems in stronger winds and rougher seas?

 

[geem]

Thanks, that looks simple enough. Have you had any problems in stronger winds and rougher seas?

When the seas are bumpy, in fact most of the time whilst sailing, I have a line from the outer edge of the panel to the bottom guard wire that stope the panel bouncing off the wooden strut.

 

[KellysEye]

>I believe that the basic Rutland 504 sells for around £350 whilst the Ampair 300 is around £1,600.


Like everything in life you get what you pay for, if you want high power output it's worth buying Ampair, it you want a lot less power buy a Rutland

>Solar 145W panels: 50Ah cost (£200)
Ampair 100: 25Ah (£880)

That's not a fair comparison you don't say how many solar panels and you have purposely chosen a lower output Ampair than the one I gave details for.

 

[the lloyds]

I have bought some very neat Swedish brackets made by Noa to do this in the Dodger position. [Sold by Seateach- Emsworth]

We have bought two x 85watt hard panels made by Victron that have a high level of efficiency.

The brackets are not cheap but nicely made in aluminium and you bolt them to teh panel frame . They have a facility to turn the panel towards the sun or conversely lock it down like a Dodger.

Nice stuff though not cheap at ? £65 each set. Really pleased with them so far

 

[Koeketiene]

I have bought some very neat Swedish brackets made by Noa to do this in the Dodger position. [Sold by Seateach- Emsworth]

We have bought two x 85watt hard panels made by Victron that have a high level of efficiency.

The brackets are not cheap but nicely made in aluminium and you bolt them to teh panel frame . They have a facility to turn the panel towards the sun or conversely lock it down like a Dodger.

Nice stuff though not cheap at ? £65 each set. Really pleased with them so far

We got those brackets too (4x100W).

 

[Mistroma]

>I believe that the basic Rutland 504 sells for around £350 whilst the Ampair 300 is around £1,600.


Like everything in life you get what you pay for, if you want high power output it's worth buying Ampair, it you want a lot less power buy a Rutland

>Solar 145W panels: 50Ah cost (£200)
Ampair 100: 25Ah (£880)

That's not a fair comparison you don't say how many solar panels and you have purposely chosen a lower output Ampair than the one I gave details for.

The panel details were shown in post #8 and repeated in #26 (the one you were responding to in your #27). so I didn't repeat the spec. as I assumed you had read the post (56W + 2x40W, all rigid).

I failed to see how you found it fair to compare a £350 Rutland 504 with a £1,600 Ampair. It seemed fairer to compare units of similar size. This was to point out that choice of Rutland or Ampair made no significant difference. i.e. Solar would outperform wind when comparing installation cost with output.

Output is closely related to swept area and the Ampair 300 has 6.25 x swept area of the Rutland 504. The 100 and 913 are of similar size. Nobody else commented on your comparison and so it is possible that I'm in the minority here and that otheres agree you made a sensible comparison.

Looking at the specs. again, I note that I actually did compare Ampair 200 with Rutland 913. Unfortunately, I typed 100 instead of 300. I'll illustrate my point again using both the Ampair 100 and 300, sorry about that error (updated now).

Daily average
Solar 145W panels: 50Ah cost (£200)
Ampair 100: 16Ah (£880)
Ampair 300: 30Ah (£1,600)

I realise that I've only measured Rutland 913 output over several years in Scotland, France, Spain and Portugal. I have no experience of the Ampair unit. However, it won't break the laws of physics and wouldn't produce 2 x output indicated by the specifications. I actually increased my figures here by 20% to give benefit of doubt to Ampair (my original calcs. showed 25Ah/day from 300 model).

I agree with you that you I could spend £1,600 on an Ampair 300 and get more than I get using a £600 Rutland 913. However, I'd have spent £1,600 to get the same average output I get from ~75W solar panels for about £100.

I was unwilling to spend an extra £1,000 on a larger wind-gen as it gave a poor return. I'd still rather have more solar and keep the Rutland, thanks.