Pulling The Trigger..Installing Solar

[Sid at SailAway]

Originally Posted by barnakiel

Ad-hoc, I like to see double the W (-attage) into Ah (-age) of your battery bank. E.g. 100W of sol pan into 50Ah batts.

Plenty will depend on what you want the solar energy to do. Is it main and only and essential source or rather secondary and optional source. Etc.

Regulators? Well, PWM till you run out of solar space. MPPT sure if you want one, or if you are already fully paneled out. Price no issue MPPT wins.

I think, if you can afford batteries that will soak up any charge at any time, you can seriously reduce the amt (area) of panels. Given the cost of such batteries (say lithium tech), one may end up with plenty of panels and plain batteries as this is the way cheaper combo.

b.

The bank is 440ah Costco golf cart batteries which so far after two years are still working fine. I hoping with 400 watts or so of solar I won't have to run the Honda when on the hook. As it is now, the Honda runs about two hours a day with a ProNautic 12-50p charger set at 50 amps. I don't mind the Honda with the exception of disturbing possible anchor neighbors. We try to anchor away from everyone for this reason. When we're on the ICW charging is not a problem as the alternators take care of it.
I started leaning towards the smaller panels then good points were made about all the electrical and mechanical connections. Mark is right, I have a ton of space on the back on the boat and can incorporate the davits for mounting.
I did locate Kyocera 260 watt panels for $267 here..

260 Watt Solar Panel | Kyocera KD260GX-LFB Multicrystalline Module

The Solar Cynergy 240 Watt panels are $192. The question is, is the extra $150 for the Kyocera panels worth it? I say yes, just for peace of mind in buying a known panel. Thoughts?

The problem I have found with the suggested kits has been none of them come with a MPPT controller.

Thanks for all the responses so far. They have been very helpful. I'm just about clueless when it comes to electrical in general. Every little bit helps in the decision process...

[newhaul]

Actually the pwm controller will do you just great its not worth the extra cost until you are approaching the 2 to 1 ratio of watts solar to an ah of battery capacity.
In other words you can benefit from mppt if you have 600 watts of solar for your 440 ah of battery. ( hoping Mainesail will chime in soon )

[twinboat]

Newhaul, You need a MPPT controller with grid tie panels, like the 260 watt ones listed above.

I have 8, Sams Club 6 volt batteries, 3- 225 watt, 36 volt panels in series and a Morningstar MPPT 60 controller.

Before the solar, I was running the Honda, with a 50 amp charger, 4 + hours a day.

Now I run the Honda, once or twice a month, only after a few days of rain.

You will love it

Sent from my VS840 4G using Cruisers Sailing Forum mobile app

[msponer]

Originally Posted by Sid at SailAway

The Solar Cynergy 240 Watt panels are $192. The question is, is the extra $150 for the Kyocera panels worth it? I say yes, just for peace of mind in buying a known panel. Thoughts?

Oh, I misread your first email and thought you were going to buy the Cynergy panels from Home Depot for $385/each. That seemed outrageous since the Kyocera's are less.

But you'll have to pay truck freight to buy the Kyocera's from Northern Arizona Wind & Sun. That plus the $150 price difference may make it not worth it.

MPPT controllers are expensive. But you need one to attach the high voltage panels to your 12v system. Sorry to backtrack your train of thought, but if you don't want to blow money on an MPPT controller, it may be less expensive to use four smaller 12v panels, as other people suggested. Then you can use a cheaper controller. Large panels (as the ~250 watt ones are) only come in higher voltages.

Though include the cost of how you will mount the panels. If you plan to use the fancy stainless solar panel pipe clip things, the cost for needing twice as many clips could equal the price difference of an MPPT controller.

I think your ~400 watts of panels will make the ~100 amps/day you've been making with your Honda. I'm extrapolating out from how much our 750 watts of panels make in the Caribbean, which always have a thin shadow (or two) from our split backstay on them. We had to run our Honda at ~50 amps for 1-2 hours a day, and our batteries are now full by mid-morning.

[socaldmax]

Originally Posted by Sid at SailAway

I do like the idea of 4 smaller panels instead of two large ones. My largest power draw has to be refrigeration. I have one compressor (BD35's) for the fridge and two for the freezer. I do shut down one freezer compressor when on the hook so we don't have to run the Honda genny as long to bring the batts back up. Other then that we have led lighting, fresh water pump, pump for the water cooled freezer compressors, anchor light is still incandescent and of course all the nav gear when underway.

I prefer larger panels. I can guarantee you that 4 of any brand of 100w panels will weigh more and take up more room than 2 of any brand of 200w panels.

There is a single 425w panel that takes up far less room than 2 x 200w panels.

In fact, I've seen older 155w panels that were only 2 inches shorter than the 425w panel. Put another way, 2.74x more power in a single panel only 2" longer. Imagine, 270 more watts just for an extra 2 inches of panel length. Why waste precious space and add unnecessary weight aloft by using smaller panels?

[barnakiel]

You are not limited by your panels, stop worrying. You are limited by your batteries' (lack of) ability to accept solar power when it is available. You would have to operate very drained batteries to get the acceptance levels BUT doing so kills batteries prematurely and this in turns makes you pay in batteries what you are saving (if at all) on
diesel.

If you feel uncomfortable with this finding, read on about how much solar energy you can store into your batteries at each % level of their "fullness".

IF (big IF, intentional) your loads are so that you can switch them off at any time or/and/if you have loads that can be used to utilise the "excess" solar power, then you are fine. A watermaker is a fine example here (offshore or anchored in a very clean anchorage).

Solar energy is a cool thing. Our habits of how and when we need electricity are less cool. You cannot change your habits. Nor can you affect when and how much the sun is shining. Cul the sac.

I say get the most solar area you can and the best regulator you think you want, then see where this kit gets you. Then adjust your policies.

PS I think paying some extra for quality panels does make sense. We have one old (Siemens) one new (Chiniens) panel. Somehow, the new panel looks older than the old panel (yes, I know, Woody Allen felt this way too).

Cheers,
b.

[socaldmax]

Originally Posted by msponer

I also think those panels are over priced. I bought 250 watt Kyocera panels last year for $250/each. I don't know anything about the Grape brand of panels, but Kyocera has a 10 year warranty and good name.

I am not a big fan of the Solar Boost controller. I have one on my RV (which has two 120 watt panels). The terminal block seems a bit rinky dink and not suited for large wires. The metal face also gets worryingly hot. It still works fine, but for the boat I used a Morningstar Tristar-MPPT controller, which has a big heat sink, better diagnostics and more advanced configuration (for charging voltages and automatic equalizing and etc), a higher quality terminal block (that accepts large wires), and overall just seems higher quality.

I don't agree with everyone else about getting a bunch of smaller panels. I feel that's just more connections and bolts. I think you should keep in mind when you mount the panels that, if you break them, years from now you may not be able to get a new panel with the same dimensions. So, if possible, mount them in a way that there's a little room for adjustment. I would also leave room for more panels (by putting them to the side instead of the center, for example, to leave a big space for more), if possible -- I feel 500 watts may not meet all of your needs. But 750 or 1000 watts may.

We've recently gone from 'too little' to 'way too much' solar, and it's a nice lifestyle improvement. To not even worry about energy any more.

I agree with everything he's posted here.

I also have a Blue Sky SB2000e in an RV, and while it works, and has been reliable, it has very small contacts for the wires (I had to splice much smaller wires on the ends to make the connections) and I didn't like having to make the voltage adjustments from the rear, plus that model is limited to 12v panels. Since I bought that controller, I've found better, cheaper, easier to use controllers with better heat sinks.

I also agree with larger panels, carefully placed so as to eliminate shading.

I also agree with the Morningstar MPPT controller recommendation, although, for the price difference between the 45 amp and 60 amp models, the 60 amp is a much better deal for just a few $$ more. I've installed 2 of them so far (with 690w of panels ea), and was very impressed with it's 150v input capability, so you could connect several panels in series which is nice for less line loss - provided you don't get much shading. The new higher output panels are pretty high voltage, so the 150v input controllers come in really handy.

[socaldmax]

Solarblvd.com also has great prices on panels. I don't know where you're located (hint for those of you who like to put the cutesy "wherever my boat sank" as their location - when you ask for help, you're not doing yourself any favors because the most helpful answers may depend on your actual location) but I bought a 10 pack of 230 watt solar panels from them for $1350. Sold 6 of the panels for $1700 and still have 4 left, plus $350 profit in my pocket, plus the labor I charged for installing the other 6... you get the picture.

You could order 10 of them, put a bulletin up on the local yacht club board selling the 230 w panels for $270 ea, sell 5 or 6 and you got yourself 4 or 5 x 230w = 920w - 1150w of solar panels for free.

[newhaul]

Originally Posted by twinboat

Newhaul, You need a MPPT controller with grid tie panels, like the 260 watt ones listed above.

I have 8, Sams Club 6 volt batteries, 3- 225 watt, 36 volt panels in series and a Morningstar MPPT 60 controller.

Before the solar, I was running the Honda, with a 50 amp charger, 4 + hours a day.

Now I run the Honda, once or twice a month, only after a few days of rain.

You will love it

Sent from my VS840 4G using Cruisers Sailing Forum mobile app

You are correct for the grape solar panels. I got lost a bit there were several other smaller panels at 100 watt each for a set of 4 at 400 watts total output and those panels have a top voltage output of approximately 18 volts unloaded. So a pwm controller would do the job quite well with the smaller panel setups.

[AlwaysFORSAIL]

Look up KISS in Tarpon Springs, FL he is full of good info. I have 3 85 watt Kyocera panels and couldn't be happier. Cost me about $2000 including frame for mount and labor to install.

[Hyprdrv]

Hi Sid,
I'm looking at doing solar for my House bank on EG. Maybe we can get together on some panels and save a few bucks.
I'm planning on doing the Davit thing with 2 panels and a MPPT controller. The comments on a controller excepting large wire size is a good point to remember. Larger is better for the components and a consideration when sizing the system. I'm planning on running inside the davits and in a parallel configuration.
You got my number so give me a call.


Steve in Solomons MD
Lagoon 410 S2E

[barnakiel]

Originally Posted by msponer

(...)

I think your ~400 watts of panels will make the ~100 amps/day you've been making with your Honda.

(...)

This is one of the important points: you can start the Honda when it best suits your optimum charging regime. You cannot have this with solar panels.

So, to put it in lay charging terms: 100Ah solar NOT = 100Ah genset. Because you cannot 'switch on' the panels when it best fits the batteries' acceptance rate.

Also: Honda is shinning every day ...

b.

[barnakiel]

Originally Posted by Sid at SailAway

(...)

I have one compressor (BD35's) for the fridge and two for the freezer.

(...)

And this is the second major matter. And how to go about it now.

You want a decent (V,A,Ah,%) power monitor up first. Then you want the boat at the dock. Then you run your bats down to about 80% full and at this point you disconnect the shore power, switch off all other systems (leaving only the three compressors on), zero the meter and start metering. Leave the boat like this for 48 hours. Then divide the Ah consumed by two. And also note how much % charge is left in the batteries now. (Too low % charge will kill you batts sooner).

The above will tell you how much solar Ah you need to get somewhat genset independent (not 100% independent at all).

IMHO it is most highly unlikely that you will be able to put the genset away. But perhaps you will be able now to start it every say third day, if cruising in very sunny areas.

(PS Throw the compressors overboard and you will be 'flooded' with sudden excess of solar energy.)

Cheers,
b.

[twinboat]

Barnakiel , did you have a bad experience with solar, you seem so negative.

I am running a household frost free, refrigerator, on a xantrex PSW 2000 inverter.

We live full time on solar. I watch satellite TV, every night, we use a slow cooker, toaster, microwave and computers, when we want. We have been doing this , for over 6 years.

We only run the Honda occasional, in winter, due to short days and low sun.

To the OP, Take some time to time your refrigerator compressors run time for a few hours. They draw between 2 and 3 amps. That will give you a ballpark figure on ah, used.

My refrigerator draws 8 amps, dc when running.

You also need to remember, the solar is supplying all of your usage and charging , during sunny days. You only need to calculate energy use for 16 to 18 hours a day.

In winter I run between 60% and 80% charge, most days.

In the spring, thru summer I run between 80% and 100% state of charge.

Good luck with your system.

[barnakiel]

Originally Posted by twinboat

Barnakiel , did you have a bad experience with solar, you seem so negative.

(...)

In winter I run between 60% and 80% charge, most days.

(...)

Not at all. Or, at least, not intentionally. Realistic, yes.

Plenty of time here spent designing and installing solar and wind on cruising boats. Now also water turbines and fuel cells. At times, spending more time convincing owners for or against something than actually sourcing, building and commissioning the systems ... ;-)

On our own boat, we are 99% solar. (1% = the 60A alternator on the engine)

We sailed from Sweden to Australia and back and with each new set of batteries / panels and regulators I tried to adjust our newer set-ups to whatever I learned from our earlier trials and failures. And from trials and failures of other cruisers. I listen a lot, too.

Last winter we sailed to the West Indies and back (from the Canaries) without ever having to start the donkey for power. We were never below 75% full and in fact only maybe a dozen times below 95% by the nightfall (in 10 months).

If I sound like a warning, I am. And my warning is about trying not to underestimate the load that three compressors WILL place on the system. If you are happy with 60%-80%, you will be fine. But you will pay in batteries what you will make on the roundabouts. Unless you have lion batteries or similar (but then you would be 80-100%, not 60-80%).

Then again, if you intend to keep the Honda you simply start it up whenever you find fit and then no matter what solar set-up you have, you will be happy with it!

As they say, different boats, different power balances.

PS If you want some quiet power source that does kick in at whatever moment you need it, have a look at what fuel cells do. They are not for everyone but they do have some features that other sources do not offer.

Big hug,
b.