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Post by vasko on Jan 29, 2017 15:40:03 GMT
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Post by alenka on Jan 29, 2017 22:29:23 GMT
Probably one of the best bimini installations that I have seen. I assume they can be removed easily for when you want to fold the bimini away?
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Post by vasko on Jan 29, 2017 22:42:13 GMT
yep, just need to cut the cable ties and unplug the cables and store away...
the issue that I have is that I want to have about 600watt solars, but found space for for total 240 + 120 = 360 - need to find space for another 240...
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Post by Mistroma on Jan 30, 2017 16:53:54 GMT
Yes, it's a struggle. The 100W version on my awning is held in place with tape looped through the eyelets and stitched together. I sewed short lengths of webbing on inside and outside of the awning, leaving a small gap in the middle of the upper webbing. Then it's just a matter of passing the loops through the gap in the webbing and pulling them tight. The front tape actually feeds back under the same webbing as tape from the rear corners and this adds a little extra support for the middle of the panel.
I thought about punching holes but decided I'd prefer to retain a more waterproof awning. The 100W panel is a bit longer than yours so able to flop around a bit more.
Improvements for this year might be:
1) Add clips to back edge of awning. The tape is simple tied there at present and adjustable clips would be better
2) Fit a couple of light aluminium stiffeners to the edge of the panel to reduce sag and movement. The panel as a bit shorter than the awning and would benefit from the extra support.
I think that I can fit an extra 100W on the awning without too much of a problem and to give 345W in total. Might have to consider the sprayhood option you have after that.
Some people will say that you panels will suffer a lot from shading. However, my view is that they are now relatively cheap and it makes sense to fill up space with them even if not ideal. I have some underneath the boom and output is poor when sailing. However, I average about 50Ah/day mid-summer at anchor with the boom pulled to one side. That's 50Ah/day for panels costing about £160 so worth having.
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Post by vasko on Jan 30, 2017 18:36:46 GMT
I have been always puzzled why people who have space for 500-600w on their boats are going with 300W or less ...
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Post by hoppy on Jan 30, 2017 19:48:39 GMT
I have been always puzzled why people who have space for 500-600w on their boats are going with 300W or less ... It depends on how you define "space". In the med my spray hood spends 90% of it's life folded and only goes up when there is spray coming into the cockpit, rain and if the Meltemi was blowing like crazy at anchor. The bimini comes down often when I want to "sail" my boat rather than cruise along.  |
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Post by vasko on Jan 30, 2017 21:14:04 GMT
I'm in the med also but still I use my speayhood all rhe time and when hot I just fold the font completly But for the solar panel's I was not implying bimini or soray hood as both are king if "hack" for solar panels I was thinking for a arch with 500-600w solars , unfortunatly on my crabpod I have only space fir 240w on my arch  |
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Post by vasko on Jul 10, 2017 22:33:25 GMT
After testing the spray-hood top panels instillation for about two months now and in almost every weather ( so far up to 42kts wind), directions sailing, wind etc. I can confirm that they still stay as stable as the first day I've installed them, no issues with strong wind etc. all seems perfect so far , also they seems to help to stability of the spray-hood also...
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Post by so36idavid on Jul 11, 2017 5:55:11 GMT
I have been always puzzled why people who have space for 500-600w on their boats are going with 300W or less ... I have 240W of solar power and I genuinely don't need any more. If we're at anchor and it's sunny my batteries are fully charged by about 10:30 a.m. and stay that way until the sun goes down. I do need to run the engine if we spend more than 24 hrs sailing with radar and autopilot going. Or if we're at anchor and it's cloudy for more than 2 days. Of if the admiral demands hot water for showers . The key that unlocks the whole thing is to have an efficient fridge. I have put a TON of effort into minimizing the fridge draw. My fridge uses around 40 Ah/day, everything else is noise. Electronics that need charging are plugged in during the day. Lights are all LED. I have 200Ah of batteries and when I get up in the morning they're usually down by around 25 Ah due to fridge running overnight. Sun comes up and the batteries are charged by lunchtime. If you need 600W then you are presumably using more than 100 Ah/day. Do you have a good handle on where all of that energy is going? I've detailed some of my fridge mods in a separate thread. Thanks to you b.t.w. for some good suggestions on that. |
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Post by vasko on Jul 11, 2017 6:19:37 GMT
Agree my electricity consumption is huge , but a little bit of comfort is good for me We are usually 4-5 pople on the boat, everyone have at least one smartphone and one tablet - some of us also have a laptop and 3x drone batteries, smart bracket/watch, action camera, signal booster, myfi, 24" tv with blueray player and active antenna, ais, fishfinder, autopilot, vhf , chartplotter, bean to cup coffe machine, aircon, watermaker(need about 120l per day) , uv water filter and I also want ice for my gin or rose . Yes all is led, but not miserable - I have 4 llight in the saloon and 1 big 20w in the middle of the ceiling, 2 x 5w in the kitchen area 5w on the chart table, and 4 reading loghts in the two cabins, 2 x in every head(2 heads) , cockpit light , 4 hi- power usb in every cabin, 8usb ports at the chart table etc... |
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Post by so36idavid on Jul 11, 2017 6:22:48 GMT
LOL Vasko, one day I've got to check out your boat. It sounds awesome!
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Post by vasko on Jul 11, 2017 6:23:35 GMT
And also forgot my new electric outboard , which I'm testing and with 1h per day minimum running it needs about another 20-40ah charge My logic is simple solar enery is cheap - then have more and have comfort |
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Post by so36idavid on Jul 11, 2017 6:28:40 GMT
I thought I had the only sailboat with a fishfinder on it, nice to know I'm not the only crazy one. Then again, we're eating sushi while our neighbors are eating dried pasta. Here's a little dorado we caught off of Mexico earlier in the year.  |
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Post by alenka on Jul 11, 2017 7:21:17 GMT
My attention was recently caught by a Bavaria that had its cockpit covered in black blobs of plastic. On closer inspection it turned out to be solidified drips of molten plastic and there tucked in one corner were the remnants of two very damaged solar panels. No one was around to get the full story but it seems for one reason or another the panels had gone into melt down.
Last winter I left my solar panels in place to keep the batteries topped up and in doing so overcharged (ruined) them. The previous winter I covered them on advice from the service engineers.
This coming winter I was planning on adding a nightly discharge circuit via the timer on the controller to protect the batteries, but after seeing this Bavaria have now decided to go back to covering them.
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Post by vasko on Jul 11, 2017 8:26:45 GMT
if your solars has overcharged the batteries - then - you solar charge controller is for the bin - ASAP - get a good cheap one MPPT ( should be about £30 or less... I leave my solars constantly ON as I do not like the risk a electrolysis - and never had any issues... - if you want to just stop them you can also just unplug them ... ( assuming any single panel is <= 120watts)
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Post by Bora on Oct 12, 2017 20:08:13 GMT
Agree my electricity consumption is huge , but a little bit of comfort is good for me We are usually 4-5 pople on the boat, everyone have at least one smartphone and one tablet - some of us also have a laptop and 3x drone batteries, smart bracket/watch, action camera, signal booster, myfi, 24" tv with blueray player and active antenna, ais, fishfinder, autopilot, vhf , chartplotter, bean to cup coffe machine, aircon, watermaker(need about 120l per day) , uv water filter and I also want ice for my gin or rose . Yes all is led, but not miserable - I have 4 llight in the saloon and 1 big 20w in the middle of the ceiling, 2 x 5w in the kitchen area 5w on the chart table, and 4 reading loghts in the two cabins, 2 x in every head(2 heads) , cockpit light , 4 hi- power usb in every cabin, 8usb ports at the chart table etc...  EPIC setup!! Now i see why you have such a power requirement. My main draws are the fridge and charging an ipad/iphone and occasionally a mac (got a 12v charger instead of using an inverter and the original charging plug) |
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Post by allegria on Oct 12, 2017 23:49:53 GMT
Hi Vasko,
I removed my 2 x 100W solar panels from my bimini recently, they were cooked. Yep, cheap eBay panels that did last 2 years.
I'm in Sydney, Australia and the sun on this side of the world is pretty harsh, but we have plenty of it!
They were AUD200 each at the time so my rationale was if they last 2 years, that's still cheap!
I had them connected in series and going into a Victron BlueSolar Charge Controller MPPT 75/15.
Originally, one of them was faulty as one of the cell shorted. It did leave a nice brown mark on the bimini from overheating.
I dodged a bullet on this occasion I believe! Anyway, it was replaced and worked fine afterwards.
I'm on the market to replace my panels and still undecided if I replace both of them or try with a better quality one instead. The other interrogation is, if I was to get 2 new panels, whether to connect them in series again.
Most blogs recommend not to connect the panels in series. Have you got a preference?
If I was to connect them in parallel, I would need to upgrade the wire going to the controller as the amp would be too much for the existing setup.
I follow with interest your posts on this topic. Your boat seems to need a small nuclear power station to satisfy your power needs!
With all you solar panels, do you actually have one controller per panel? Or do you connect them in series? or parallel?
Any opinion welcome...
Cheers,
Allegria
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Post by so36idavid on Oct 13, 2017 6:01:05 GMT
Allegria,
I would definitely parallel the panels. They're very sensitive to shading. If they're in series then shade on one panel will open the circuit. I think you'll get much better energy production from parallel panels. I would give each panel a dedicated MPPT controller. So you'll need to run a new set of wires but the old ones will be sufficient for one of the new panels.
David
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Post by vasko on Oct 13, 2017 6:13:20 GMT
The best strategy is separate controller per panel , second best is in serries and mppt, and last (clasic one ) is in parallel
In my case my panels are in parallele 2x120w, 2x60w and this winter will add another 1x60 and 1x100 ... and will change to new controler epver mppt 40amps (my current one is 30amps and will be on the edge with total 529w)
Btw : re david post actually my understanding is that if you connect the panels in serries with mppt you are solving the problem with the shade - e.g. shade problem arrises when in paralkele
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Post by rene460 on Oct 13, 2017 8:49:00 GMT
Hi allegria,
I am not so sure about that series connection. The panels are generally rated at around 16 volts, so the current, (under "standard sunlight" of 1000 watts/m^2), for a 100 watt panel is 100/16 or about 6.25 amps. The voltage current characteristic means that if you just connect this one panel to a twelve volt battery, you get a bit more but you will not get 8.33 as you might expect. But look up the specification sheets for your panel for the actual curve and number. If you put two such panels in parralel, you can add up the amps, and expect 12.5 amps still at about 16 volts. Under Australian sunlight conditions, I have found you can sometimes get more than the ratings suggest, which tells me that at times we do get more than that 1000 watts/m^2 intensity, so you do not want to cut it too fine with the regulator rating. I would suggest about 20 amp capacity would be suitable. If you put two panels in series then you still only get 6.25 amps but now at around 32 volts, though it will still more easily exceed 12 volts in cloudy conditions.
Now that that is the input to your regulator. A standard regulator takes that 16 volts and essentially drops about 2 volts, basically losing the power, and can supply about 14 volts to charge the battery, similar to the alternator voltage. Now the MPPT type I am not so sure about. It is working with DC not AC. I know they can take a lower voltage and with a clever circuit, boost it enough to feed the twelve volt battery with the current available from the average power when sunlight is low, but I don't know if the boost circuit can work the other way and take a higher voltage and use the excess to boost the current. It would be interesting to see the manufacturers data sheet and description. I would want to check that first, because it would have to waste 100 watts as heat on a sunny day if it cannot. That would tend to overheat the circuit if it does not have very good heat sinks. Vasko, are you sure it can work to get the full power of the series panels? How do those MPPT controllers really work?
If the two panels receive equal sun without shading, I would prefer parallel and possibly one regulator of 20 amp capacity. However if one might receive less, or worse, be shaded at times, then separate regulators would be better, as you would still get full output from the one not shaded. The shaded one produces less voltage, so diodes need to be fitted as part of the panel, otherwise it could actually absorb power from the other one, and this could contribute to premature cooking of the panel. Again the data sheets should cover this.
Then there is always the question of smart chargers, which may or may not apply to solar regulators. However, if they depend on various voltage interuption tricks to determine the state of battery charge, these tricks are possibly not compatible with parallel devices, let alone the combination we typically see where we have solar, engine alternator or shore powered charger, and some also have wind power, all contributing. I would be greatful if anyone can shed any light on how this works.
In summary, I would go for fairly two standard MPPT chargers and parallel connections. And if the cheap panels don't come with a data sheet available, at least on the manufacturers website, it is too cheap!
Sorry to be a contradictory opinion, but these questions are often a little more complex than they seem, better to get the basics sound before spending too much.
rene460
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Post by so36idavid on Oct 14, 2017 3:16:51 GMT
How do those MPPT controllers really work? Hi Rene, This may be a bit technical for some so if you really don't care about these things then just plug the wires into the controller (in the order specified in the instructions!) and go sailing. It's basically a DC to DC switch mode power supply. If you look at the power/voltage curves for a solar panel you'll see that for any given solar condition there is an output voltage that maximizes the power out of the panel (power is voltage times current). This is known as the Maximum Power Point (the MPP part of MPPT). Using solid-state electronics the controller presents the ideal resistance to the panel so that the voltage sits right at the MPP. But that means that the voltage coming out of the panel could be anywhere from around 16 to 24V. The battery can't use that voltage. So using solid state switching the controller transforms the DC input voltage into an appropriate DC output voltage to provide ideal charging to the batteries. Most of them use a typical 3 stage charging algorithm. Since it maximizes the power out of the panel it has the maximum amount of power available to feed the battery. There is very little power lost in the controller, typically 1% or less so they don't get very hot and don't typically need external heat sinks etc. The old style PWM controllers work very differently, they don't optimize the power out of the panels and in order to present the "right" voltage to the battery they basically dump power into the heat sink. I would not recommend installing a PWM controller at this point they're cheap but obsolete. David |
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Post by so36idavid on Oct 14, 2017 3:24:56 GMT
P.S. Here's a picture of the controllers on my boat. You can see the whole install here.  |
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Post by vasko on Oct 14, 2017 3:44:52 GMT
P.S. Here's a picture of the controllers on my boat. You can see the whole install here. very nice looking setup! - just one comment : controllers very close to places where you can have acidents with sprays of water - muffer and shaft seal... - also how you measure how much amps you are getting from the panels ? I cannot see any LCD on the controllers ... |
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Post by rene460 on Oct 14, 2017 6:57:02 GMT
Hi David,
Thanks for that very clear explanation. Exactly what I needed and no more. Basically I prefer to just plug the wires in in accordance with the directions and go sailing, but I am a bit pedantic about those instructions, and try to check carefully that I am using equipment within specifications. My experience in commissioning of large machines makes me very wary of black boxes. I like to know enough to know what they will do with less normal situations which of course, you always see when starting up, especially the first time.
So a good MPPT controller should be able to make use of the full power available from series connected panels, with the advantage that it would continue to feed some current to the battery into dusk, when even the series connection might output a total of less than 12 volts? So long as the maximum voltage is within the specifications for the unit of course. I presume the three stage algorithm is mostly about battery voltage and tapering off the charging current, but is it affected by other chargers such as the engine alternator operating at the same time?
What happens then when one of the series connected panels is partly shaded? Does this just reduce the overall output voltage? Or does it cause a high resistance path through the shaded cells, which might lower the total current?
Sorry to have so many questions, but I don't believe I have seen them answered before on the forum, or anywhere else that I have found.
rene460
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Post by so36idavid on Oct 14, 2017 14:37:35 GMT
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EPIC setup!! Now i see why you have such a power requirement.