1kw+ of solar - how to do it cost efficiently?

[sailorboy1]

Personally I would take some of the 1000W solar money and upgrade my battery charger!!!!!!

[baycruiser]

I of course think my way is best but for your consideration I use ac where possible that means frig hot water etc. mine is 240 but you may be 110 but anyway I use house type 24vpanels and a 24v battery bank for good but not excessive inverter ac appliances I find more reliable and much cheaper to buy and replace my 24v bank is usually on float by 9am so then the rest of the day I use my power as I need it and I turn my very good quality battery charger on for my 12v battery bank both banks are the cheapest n70 or truck batteries this system has been very reliable 24/7 for 2yrs and cost much less than 2k .MUST use real good short simple wiring and DIRECT monitor often So yes I use a 12v system lite.lav.winch.motor.fresh water.tv,s.. 24v for all ac frig hws.toaster.fans.chargers.try it do the math I have done a few like this it works Infact I never start my very small cheap generator dont need it or marinas power leads

[autumnbreeze27]

If your batteries are older, you might consider going Lifepo4. You'd need 1700ah to equal your 2600ah lead acid bank. You will gain efficiency charging and discharging.

We have 4 renogy 100W panels and 4 lensun 100W flex panels connected to a Morningstar MPPT60 and 400ah of Lifepo4. If I could do it over I'd probably go with 4 victron 100/15 controllers for fault tolerance and better performance.

Avoid the cheap MPPT's, I tried splitting my array into 2 with a cheap mppt and it was not as efficient as just everything on the morningstar.

[a64pilot]

Originally Posted by sailorboy1

Personally I would take some of the 1000W solar money and upgrade my battery charger!!!!!!

There is a lot of logic here, if it's just for vacations every once in a while and not full time living.
Even done frugally, a couple of KW of Solar I'd guess is going to cost $4 to $5 K, and that is a whole lot of Diesel, unless your full time, your unlikely to ever break even on the panels.

[a64pilot]

Originally Posted by briblack

we've got 1kw. on a 46' sailboat. It's center cockpit, so we've got two 250 watt Kyocera panels on the fixed bimini over the cockpit, and two more on the arch aft. each pair goes to it's own Morningstar MPPT controller. provides a measure of redundancy for breakdowns, etc. works fine, no complaints. If I could, I'd make the panels articulate in at least one axis, to increase yield further. we often see 30 to 40 amps going towards the house bank, but since it's seven, group 31 batteries, it's only 4 to 6 amps each. not a drastic charge. but we're doing OK, it keeps up, day to day. we're running Firefly batteries, which tolerate partial-state-of-charge better than most.

You only get 30 to 40 total, or is that 30 to 40 after house loads?
What do you get on average total?

[smac999]

How big is your gen?

First of all 2700ah on a boat is rediculas.

What is your daily. Usage?

And 2nd 100a charger is also rediculass for a bank that big. even 1/3 that big. If you have a big gen. and run it anyways (cooking, hot water etc). You need more chargers.

If you are hoping to never run gen with solar then it's less of an issue.

[sailorcherry]

Originally Posted by Olly75

first rule of solar is to use as little energy as possible. So before speccing or designing the system sort the fridge out, either insulate it change the compressor or both. Then look at the other systems, like lights and change for led's etc.

I agree. Changing the fridge/cold plate compressor can half (or better) its energy use. Research the manu and update it (or replace).

Example, we found them direct, as in bought it from Poland, not via the US distributor, paid $44 in duty and waited a little longer but overall paid almost half by going direct (also thanks to the weak Euro). If you aren't an expert in these fields then maybe you might want to consider hiring one to analyze. Spending a couple hundred bucks on someone who can really nail down your usage and future expectations along with knowing where to buy for the best price can really pay off.

Lastly, consider if I were you I'd windage with such massive panels (300w size).

[trifan]

Originally Posted by BayouGrande

We've got a 50' trawler with a flat roof and, after a month in the Bahamas and DR, we've realized we need solar. The generator can't charge our 2700ah 12v house bank quickly enough (100a charger) to make sense and our inefficient refrigeration draws the bank down quickly.

I'd like to add 1-2kw of solar, ideally 1.5. I've looked at Renogy kits but am curious if it would be more cost effective to piece it together myself. Anyone do a similar system or have any suggestions?

Thanks

I have had good results with these people:
Affordable Solar - Wholesale Solar | Solar Panels | Inverters
YMMV

[tomfl]

Originally Posted by BayouGrande

Thanks. All the lights are Led. It's cheaper to add solar than redo the refrigeration given our boat.

What ever you do about upgrading your solar you should definitely talk to someone about the cost of redoing your refrigeration. With the house battery bank you have you should be hearing the tinkle of ice cubes in your drinks at sunset every night.

I have ~415 watts of solar going to a ~430 house battery bank and on a normal sunny day by 10:00AM I am dumping power. I have an Engle in the cockpit/salon and a Frigaboat (which makes ice daily) in the galley. Normally I charge my laptop daily, and more infrequently batteries for other toys like a quadcopter and cameras. My older smart phone runs Dragqueen when I sleep and it is plugged into a cigar lighter outlet. The fan for my composting head runs 24/7.

Bottom line is that you are using too much power and I am not sure the source is just your refrigerator. Often times the wiring in a boat will get worse over time for many reasons and just throwing more power at the problem is not the answer. The better solution is to get a good idea about where the power usage is going first. It may well be there is a short somewhere that is eating up power.

[BayouGrande]

All, thanks for the advice and input. We are, without a doubt, using too much power. Two mini fridges and two edgestar freezers consume most of it. Add in DVD player and TV some evenings, laptop, electronics, water pump, ice maker from time to time, and the list goes on. We are full time liveaboards for the next year or two and we are spoiled. We use roughly 600a a day as best I can tell. I know, judge away...

We run a 16kw genset partnered with a 3kw inverter that puts out 100a peak charging. Solar should pay for itself in 3-5 months. The house bank isn't even tied to the alternator (on the list but we don't move much except for long passages). We have a flat roof, roughly 13'x38', so plenty of room. Another charger would help but they're not cheap so might as well put the money towards solar. As it is we can't leave the boat for more than a day. We need a way to maintain batteries without running the genset.

With that out of the way, what I'm hearing is that a residential system with high output panels (250+) and one, maybe more, controllers is the way to go. There's a few vendors in Puerto Plata I may call tomorrow. If anyone has specific panel, controller, vendor, or setup suggestions I'd love to hear them. Thank you!

[Steadman Uhlich]

Howdy All!

I have started a new thread on CF that is to serve as an "Illustrated Guide to Solar Installations on Boats"

I hope you will participate in that thread too, by posting some photos and answering a few questions related to your own Solar Installations. The questions are easy but may help others.

The new thread is not intended to take away from this current discussion, but is intended to provide an easy way to look at a lot of different installations for ideas and information. I hope you will add to it too.

Here is a link to that thread:

Illustrated Guide to Solar Installations on Boats
Illustrated Guide to Solar Installations on Boats - Cruisers & Sailing Forums

[smac999]

With a 16k gen and 2700ah battery bank you should be running 400a+ of charging.

At 600 ah a day usgsge. Now your gen time is 1.5 hr a day instead of 6 hours. With 3 more 100a chargers. Like the mastervolt 12/100/3 .

Then cut your usage down to cut gen time ever more.