Solar Upgrade verse Running the Generator

[sailorboy1]

So on my project list is to add more solar panels to my boat. I currently have 290W and know based on the past 11 months that doubling it would mean getting batteries basically fully charged each day while at anchor/moored with the living on the boat loads. When I installed my current system I based all the wiring and controller on having 2 (should have just done it then). The cost projection is $560-725 for the project depending on if I get a second panel not identical to the one I have (manufacturer closed) or 2 new panels the same.

But since I installed the panel I also bit the dust and added a diesel generator to the boat. I know that running the generator about an hour in the morning is enough for my current panel to do a good job on the battery charging. Using $3/gal I can buy 186-241 gals of diesel for the generator and it uses 1/4 gph. So thats 744-964 days of generator operation at anchor or moored. And of course running the generator has other reasons/uses and it needs to be run regularly.

So - talk me into one or the other.

[Cotemar]

Solar is by far the best way to go.

There is no sound and they are maintenance free. Life is good like that.

Here is my winter project 3 of the SunPower X21-345 panels = 1030 watts.

Each panel will be on its own Victron 100-30 MPPT controller

A good rule of thumb is to have 300 watts of solar and 300 Ah of batteries per refrigerator or ice-maker.
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[john61ct]

Solar, silent and clean, save wear and tear on the genset.

You'll still use it some mornings to ensure bank gets to 100% from solar, just needed less often.

[Kenomac]

The generator is still a good investment because with solar you get zero when the sun doesn't shine. But on sunny days, it's nice not having to listen to the generator for an hour. Your choice has more to do with quiet time. Our 450w of invisible Solbian solar takes care of everything including cooking, unless I turn on the large deep freezer.

Double your solar and enjoy the generator when it's needed.

Note: We're now in the habit of moving the boom off to the starboard side and attaching a stabilizer to the boom end daily in order to eliminate shading issues and improve motion. It's been making a significant difference on solar production along with having installed five controllers, one for each panel.

[Davidhoy]

Originally Posted by Cotemar

Here is my winter project 3 of the SunPower X21-345 panels = 1030 watts.

Do you mind me asking what you paid for your panels, and where you got them?

I've been trying to source some Sunpower panels, but the prices I'm getting quoted, from the very few places that seem to sell them, are 2-4 times what you'd pay for a similarly-sized (physical size and watts) panel from Panasonic or SolarWorld. I keep hearing that Sunpower are the best, but are they worth that kind of multiple?

Thanks,
David

[sailcrazy]

We have a genset as well as 240 watts of solar. We run the genset every day to cook as we converted the propane locker to another hanging locker in the mastersuite, and changfed to an electric stove (Admiral's choice!). But it makes it easy to use the batt chrgr if needed and/or make water, etc. We think it's good to have options,especially for those overcast days, and, as you mentioned, you need to exercise the genset with some regularity. We rarely run it for more than an hour.

[Tom and Maje]

I've got a1000w of solar and 600ah of house batteries. To take advantage of the solar I need to add about anther 400ah to the house Bank. On a good day my house is charged by noon and I can start making hot water and run my ice maker of the solar

[Martin S]

Other thoughts i) wind power ii) cut electricity consumption. The later may not be popular, although chasing more power seems to be never ending.

[Kenomac]

Originally Posted by Martin S

Other thoughts i) wind power ii) cut electricity consumption. The later may not be popular, although chasing more power seems to be never ending.

Windpower is not worth the money or noise, especially when the OP already has a generator which can cram in more amps in one hour than wind can do in two windy days. My suggestion is to double solar and limit shading in order to take full advantage.

[john61ct]

Originally Posted by Tom and Maje

I've got a1000w of solar and 600ah of house batteries. To take advantage of the solar I need to add about anther 400ah to the house Bank. On a good day my house is charged by noon and I can start making hot water and run my ice maker of the solar

Actually that's ideal, since your design should be based on a few overcast days in a row, still getting the bank to full.

A holding plate fridge is another good excess power load dump.

[skipgundlach]

Originally Posted by Davidhoy

Do you mind me asking what you paid for your panels, and where you got them?

I've been trying to source some Sunpower panels, but the prices I'm getting quoted, from the very few places that seem to sell them, are 2-4 times what you'd pay for a similarly-sized (physical size and watts) panel from Panasonic or SolarWorld. I keep hearing that Sunpower are the best, but are they worth that kind of multiple?

Thanks,
David

David, did I send you my data? CRS but what I think I remember is that I did. Drop me an email if I'm mistaken, and I will.

[skipgundlach]

Originally Posted by Davidhoy

Do you mind me asking what you paid for your panels, and where you got them?

I've been trying to source some Sunpower panels, but the prices I'm getting quoted, from the very few places that seem to sell them, are 2-4 times what you'd pay for a similarly-sized (physical size and watts) panel from Panasonic or SolarWorld. I keep hearing that Sunpower are the best, but are they worth that kind of multiple?

Thanks,
David

If you can get the same wattage in the footprint of a Sunpower panel, it nearly certainly is one of the manufacturers that use their cells, because the efficiency would govern the space needed for a given wattage.

So, I suspect that if you look again, it's not one or the other of 'similarly sized' panels or or watts in that size.

Real estate matters. If you have lots of it, the cheap (less efficient) panels will deliver their watts in a bigger footprint.

If not, or you simply must have the most watts possible in your real estate, Sunpower is currently the game you have to play.

That said, and I have to apologize yet again (this and several other threads) for not yet having my battery and solar upgrade story and pix yet, let alone dropped into CF and other places.

Our upgrade literally changed our lives. OTOH, if I have a charging source that I must run for other purposes, I'd certainly use it, particularly since any time you run dino for any purpose, heavily loading it is best both for the motor and efficiency of the fuel you burn - so if you have to run the genset, by all means use it to charge.

As to my solar upgrade, and Sunpower, anyone who'd like my source and details on our 2x360 upgrade from 3x Kyocera TW 370, in substantially the same footprint (about an inch bigger than the other, on all dimensions, total), please drop me a note skipgundlach@gmail.com (not PM here) with the subject SolarUpgradeNotes so it drops to the right folder, and I'll send it off.

I know of two boats who are diverting to Vero Beach based on my info, to get their panels and install them there...

[Kenomac]

Originally Posted by Cotemar

Solar is by far the best way to go.

There is no sound and they are maintenance free. Life is good like that.

Here is my winter project 3 of the SunPower X21-345 panels = 1030 watts.

Each panel will be on its own Victron 100-30 MPPT controller

A good rule of thumb is to have 300 watts of solar and 300 Ah of batteries per refrigerator or ice-maker.
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.

Those things are enormous and weight 41 pounds each. Makes sense only on a catamaran like yours.

[john61ct]

If you were able to fit a genset's weight in panels and get rid of the genset. . .

[sailorboy1]

I'm not worried about the weight of a solar panel that weighs about the same as 5-gal of water. I decided not to go cruising on a floating feather.

I'm also not very interest in spending twice as much to have a noisy wind generator that produces less power in the long run than the extra solar panel.

I'm also not very interested in people telling me to just reduce my power use that goes along with my known boating lifestyle.

Focus on the topic question people.