Cruisers & Sailing Forums (
-   Electrical: Batteries, Generators & Solar (
-   -   sunpower x21 (

CFR 22-10-2013 02:36

sunpower x21
Hi, after reading all infos here and checking most datas found in the net plus talking to a local installer i confused and i need your help.

I have a monohull with limited space and i could use only my arch which is 1.6 m wide for the solar panel. Ofcorse a radar and air x is already installed which might give some shade but i am willing to scrap the air x although i just bought the spreco blades.

Question: i like the new sunpower 345 panel which comes arround 800 Dollar here in europe but it looks like i can only use a expensive Mppt controller who can handle th max 70 C from the panel / Tristar or outback. So it will costs me another 700 usd so all in will reach 1800 usd for a one panel installation.

Compared with a simple 140 w / controller setup which i could have for 3-400 usd it is a tough decision.

Any advice ? My batteries are 2 x 6 V Trojan 435 AH AND i have no fridge sofar, 30 AH at anchor, 80 AH sailing i need .

I am in Portugal and will visit the sunny Med next year

noelex 77 22-10-2013 02:49

Re: sunpower x21
Yes it would need a MPPT regulator. The higher voltage panels will deliver very little power without the voltage conversion technology.
Have a look at the Rogue controller it is an excellent lower cost (compared to outback and Midnite) MPPT controller. They are just about to bring out a new model. The old model I think did not have enough capacity (check anyway) to operate on your panel, but they have hinted on a bit higher specs for the new model so you may be in luck.

I suspect you will thank the greater power of the larger panel long after the price has been (almost :)) forgotten, but as always these value judgments are difficult to make for someone else.

noelex 77 22-10-2013 03:02

Re: sunpower x21
The details of new rogue controller are here:

Rogue Power Technologies - MPT-3048 30A MPPT Charge Controller

With my lousy internet connection at the moment I cannot download the handbook ( check the maximum recommended solar panel wattage not just the max current output) or send them an email.

CFR 22-10-2013 03:05

Re: sunpower x21
Hi and many thanks, looks interesting and it seems the datas fit to sunpower i will contact them

CFR 22-10-2013 04:09

Re: sunpower x21
Another point, all the "so called" marine solar experts mentioned that such a panel is too big and i should stay with the small ones in 12 V which they are selling....... any experiences ? I read here that severyl readers have it on their boat installed allready.

boat-energy 22-10-2013 11:48

Re: sunpower x21
Hi :) ... I would suggest that it depends on the forces that will be acting on the pv module, and the thickness of the glass (most pv modules use 3.2mm). The more the module flexes under repeated load, the more likely the panel will fail. Any pv panels that use 4mm glass flex a lot less, as do any of the pv panels up to 140W or so...
With the pv module you have, you'll have to mount it carefully with consideration of the above.

All times are GMT -7. The time now is 02:31.

Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2019, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.