Mahe 36: Solar Panels and Associated Systems

[lstyles]

Al,
That looks great and just what I am thinking about! May I ask where you got your sunpower panels? Cost? I contacted the person Mark got his from and he told me they don't sell them anymore.
thanks,
Lori

[Jef & Marin, Netherlands]

Lori,
The Sunpower panels were too expensive here. I found the Sanyo HIT-N235SE10 to have the same, or even a bit higher, power/m2 at a much lower price, like 770 euro's instead of over 1400. They are monocrystalline, just like the Sunpowers. And Sanyo has a very good reputation.
These are a new type, existing since september last year.
Maybe they are a good alternative for you as well.

I have made a frame for 1 panel for bimini mounting from aluminium rectangular tube. The weight is below 3 kg, and it is strong. Presently it is being anodized, I hope to get it back in a few days. The telescopes for rotating the frame are made from (shortened) telescopic boat hooks, also very light.
I will post pictures when it is mounted.
Advantage compared to stainless steel: lighter and cheaper but a lot of work, especially the design and making the aluminium fittings.

The other panel will be mounted on the bimini, like Cotemar did, but put a little bit more forward. I still have to find out how to mount this. I would like it to be a bit burglar-proof, and allow removal of the bimini for maintenance and winter storage.
Most thieves will e.g. not walk around with Torx screws, or inner hex keys in both mm and inch sizes.

[longislandsail]

Lori
Sorry to hear you can't get the sunpower panels. I bought them from the same place Mark bought his. Did you try calling Sunpower directly and ask them for a list of there distributers and go from there. The place we got ours from can't be the only people selling them. I could call them and see if they would sell me 2 more but getting them to you could be expensive.
I paid $905.67 each including freight no tax because of Capital Improvement in N.Y.
Al

[lstyles]

Hi Al,
Thanks for the information. I am going to look around here and see if I cant get them around here and avoid the freight. What is attractive about these sunpower units is not only their efficiency but they also seem to be lighter than most other units (by up to 10lbs a piece). I will look at the specs of the panels you recommended and see what I can find price-wise. I like your idea of an aluminum frame and was actually considering the same thing as the frame can be mostly hidden. At the boat show">Miami boat show I saw they had made a frame out of aluminum angle and the panels sat on top of the bottom part of the L and were held down by something on top. I think there are lots of ways to go but I definitely want to keep the weight down so will go with aluminum for sure. I wonder if its possible to do a bolt together aluminum frame. With proper bolts it would be more than strong enough and I would avoid the need to weld it (easier to take down and store etc). I would love to see a picture of what you did Jef when you get a chance.
thanks,
Lori

[Jef & Marin, Netherlands]

Lori,
Don't forget to check the spec of the Sanyo's, they have the same weight spec as the Sunpower.
My frame is not L shape but has rectangular tube cross-section. I think the most important protection for the solar panel is reduction against torque, and only closed-section tubing (like round or square or rectangular) has a decent resistance to torque. This is also the reason for welding.
I would recommend first looking for a place that will do the welding, and a place that does the anodizing.
First anodizing company I checked wanted Euro 350 incl VAT for the anodizing, second company asked 60 euro... The frame is there now.
I will post pictures at a later moment.
My frame is 20*35 mm rectangular pipe. It fits around the solar panel with a play of 1/10' all around. It rests on the mounting pieces, and will be held in place with black kit all around, at the top side.

[islandguy5]

I can't wait to see.

[Jef & Marin, Netherlands]

Hi all,
I have now completed mounting the Sanyo HIT-N235SE10 solar panel on the davits.
The frame is welded from 35*20*2 mm rectangular aluminium tube. 35 mm is the same as the panel's height. The inside size of the frame is 5 mm larger than the outside size of the solar panel. The panel rests on the attachments for the davits and the adjustment telescopes. The solar panel is secured to the frame by black kit at the top and the bottom. The frame has been anodized black.

The frame is attached to the davits with 5 mm thick L profiles 10 cm long, welded to the frame. Attachment is by 12 mm diameter 316L stainless steel rods.

The frame is rotated using telescopic aluminium boathooks costing 9.95 euro. These have been shortened to the correct length. Determining the correct lengths of the inner and outer tube requires some mathematics.
I think these boat hooks are strong enough, as long as nobody is so @##%&!! stupid to lean on them in the middle. Adjustment is very easy.
Upper telescope pivot is plastic 10 mm, lower is 316L 10 mm, around 13-14 cm long. At the bottom side of the telescope, there is a short length of massive aluminium cylinder glued inside the 30 mm thin-walled tube.

If anybody wants to copy this system, I can make a description. Please ask only if you are serious, since describing this well is a lot of work.

I think that the system is strong, light (frame plus telescopes below 4 kg, panel 16 kg) and quite cheap. It also looks slim since the frame is around the panel.
But it is a awful lot of work, don't count hours but count days.

I am still working on the right voltages of the solar controller. Since the Solar Boost has a temperature sensor, and the shore power charger not yet, sometimes the solar controller charges to a higher voltage, sometimes the shore power, depending on battery temperature. Also the solar boost controller voltages are different from the specified voltages.

Next I will mount the bimini panel. I will do this comparable to Cotemar's method, but a bit more forward. This is to reduce the number of holes in the bimini cloth to 2.

Wires:
Wires from the davits panel and the bimini panel go through an extra (red in the picture) wire duct. The bimini panel wires will go through the port chart-table cabinet and via a factory-installed duct to the engine room. This latter duct carries standard only the Furuno GPS antenna wire in it.
Now it has 5 extra wires: for the battery monitor, for the AIS GPS antenna which is mounted below deck in the engine room, 2 solar panel wires, and an extra NMEA wire to get data from the autopilot's output to the navigation laptop.

As you can see on the pictures, power production was pretty low with the gloomy winter weather here.

[vayacondios]

Ive just sourced the Sunpower panels here in Cairns Australia.
They said they can not get the 230 Watt panels, they are not longer available, but have the E/19 series that is 238 watt.
The dimensions are same, The rated voltage is 40.5

We like the idea of starting with one on the port bimini. This allow us to get some solar and will save some money initially with us not having to do any stainless steel work over the davits.

My question is (keep in mind our electrical knowledge is very limited) that we went to an electronics shop here in Cairns, and the shop clerk said if we were installing that panel on the boat to go into a 12 volt system, that we would need a transformer in addition to the regulator (controller).
I re read Cotemar and all the other posts on this thread and don't see anyone mention anything about this. Im trying to connect the dots.
Can anyone shed some light on this?
Thanks
Rozzie

[Cotemar]

Rozzie,

All you need is a BlueSky Solar Boost 3024i as everyone else is using. The idea is that the controller will take what ever the panels output is and put 14.6 volts into your house bank.

The bimini panel is a good start and maybe all you need if you do not add another freezer.

I am so glad you can get the newest E/19 series 238 watt Sunpower panels. They are identical to mine except they put out more power and may be cheaper. Just shows you where the technology is going.

[vayacondios]

Thanks Mark,
Excellent to know! Im really excited to be working on this, and will order the controller. I think we will go down the same road as you and get one over the davits, further along so we can get a water maker, and freezer as well.
Thanks so much for your excellent posts and photos, I really appreciate them.

Rozzie

[longislandsail]

Mahe owners
I have the same set up as Mark except both panels are on the davits. Same bluesky controller. The system works great. I have a stand alone freezer and factory refrig. I put water in the icetrays before bed and in the morning they are solid ice. I am on a morring so have no electric. The frig and freezer run 24/7 The freezer is at 7 degrees and the refrig is at 35 degrees. When one or both are on the volt meter reads 13.3 when off it reads 13.8 It is a great system.At full charge the meter reads 14.6 volts
Al

[impi]

Hi guys,
Sorry to be a lagoon owner crashing in on the Mahe party, but I really need to get some sound advice here.

I have installed 5 Kyocera 135w panels on my 440 davitts.

I have a Blue sky 50 mptt controller which I am told may be borderline?

I have a 970 amp hr battery bank (deep cycle gels).

2 x Balmar alternators (150 amp) wired through centerfielder and smart regulator direct to battery bank.

The original alternators (80 amp each) charge engine start batteries only.

I have a genset / shore-power running two Victron inverter chargers (120amp x 2).
The boat is wired 220v 50hz.

Here comes the confusion:

Can I add the solar panel to the housebank batteries with all these other systems or do I need to isolate the systems from each other?

If so, is there an automatic sensor that can do this?

Do I wire the panels series or parallel ?
Safety?

Do I need to add a 6th panel if in series, or could I run 3 parallel through the blue sky Mptt controller and add another controller for the other 2 in series
Or
Add a 6th and all in series?

I have heard that running in parallel means the Mptt cannot function at optimum?

Your comments would be hugely appreciated.

[Cotemar]

impi,

WOW. All I can say is that is one SAWEET Solar setup you have.
Very impressive.

We now have (4 Mahe's) using 2 panels with around 460 Watts per boat and a BlueSky Solar Boost 3024i controller strait into a 50 or 60 amp fuse on the + side just before the house battery bank.

We also have a 115 amp alternator into the house bank.

We also have a Tecsup 60 amp shore power charger going into the house bank.

We set our shore power charger and our BlueSky controller to boost charge =14.6 & float 13.8 volts. This is because we have calcium batteries that like a higher voltage.

Some of us use series and some use parallel wiring for the solar panels.
The controller handles it for you.

We do not isolate the systems from each other.

Your best bet is to give Blue Sky Energy, Inc a call and talk to there solar engineers. They are very helpful with these kinds of questions. We all have called them ourselves.

Blue Sky Energy, Inc.
2598 Fortune Way, Suite K
Vista, CA92081, USA
800-493-7877 , 760-597-1642 , Fax 760-597-1731
www.blueskyenergyinc.com

[vayacondios]

Here's a few photos of the frame made for our solar panel that is on the davits. it's sliding. The only thing I would do different, it to change the bolts that hold the slider in place to the kind that have the handle on them so that you don't need a spanner and could hand turn. It's made from aluminium we paid about $420. We got extra support brackets just because we live in a cyclone area.

Solar panels are all installed and working, along with the Blue sky controller and display. We were totally novice at this, and were able to do it ourselves, so if we can do it, I think anyone can! What a rewarding project!

Rozzie

[Cotemar]

Rozzie,
Very nice install on the panels. One note, check your BlueSky controller install manual for the switch to up the charge voltage to the calcium batteries to 14.6 volts, so they fully charge. I am out sailing in Natucket MA. This week having no generator is great.
Mark