i'm building a system with 3x200w panels because thats all I can put on the roof of my van... i'm looking at going with renogy 200w panels and a renogy 40 or 60A MPPT to start and adding a DC-DC cvonverter as suplement... suggestions? i've already got my Big Battery 202ah lithium battery and i'm trying to get my system to use the least amount of battery in the day and most at night because it gets cloudy here for days on end sometimes in washington state...
building a system... need suggestions
- Thread starter Whitieiii
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Diysolar123
Solar Addict
- Joined
- Feb 28, 2021
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- 675
well, you have already decided on your solar panels and battery...so a few things are left:
What is the DC-DC converter for?
How about shore power to battery for charging?
you say you want to use the least amount of battery...so.. what exactly do you plan on doing with the battery power?
You should write down all the things you may use, and how much power they may take.
If you are trying to be really lean with battery power, even parasitic power drain from the MPPT unit may be an issue.
What is the DC-DC converter for?
How about shore power to battery for charging?
you say you want to use the least amount of battery...so.. what exactly do you plan on doing with the battery power?
You should write down all the things you may use, and how much power they may take.
If you are trying to be really lean with battery power, even parasitic power drain from the MPPT unit may be an issue.
ehh... i'm just being too parinoid... I wonder if I can get away with a 40A MPPT for those panels? what do I need to look for to properly size my MPPT? also I want the DC-DC converter to charge my battery while my van is running if I ever have too much cloudy days but I shoiuldn't with 140w from each panel
600 watts panels into a 12V battery is 50A
At peak 14V charging its 42.8A so a 40A SCC could work.
Nothing special about Renogy panels except a higher price so consider other brands.
MichaelK
Solar Wizard
I paid retail for my Renogy panels and I later found out they were the poorest performers, and the most expensive by a very wide margin. You'll be better off buying grid-tie panels locally from a Craigslist seller, that deals locally, with local pickup instead of shipping.
Unfortunately grid tie panels even 250 watts and larger are probably too big for a Van.
Its hard to find the smaller panels on Craigslist for cheaper prices.
yup there is nothing local to me... I just looked for used on both craigslist/facebook marketplace... everything is too small wattage or too large in physical size... I will have to pay about $350 on shipping on each panel because I don't have the money to buy all 3 at once (if I include shipping cost) so I'm going to loose about $1000 on shipping no way around it... my van roof is 48x94 and if I use 3x200w panels i'll get about 420w on a cloudy day and if I use one lage panel I'll get about the same wattage because I can't use anything over about 450w.... it will be better to go with 3x200w panels I would think?
if you have links for better panels that will fit on my roof let me know otherwise the renogy 200w is what i'll go with as I think they have a sale on them now...
if you have links for better panels that will fit on my roof let me know otherwise the renogy 200w is what i'll go with as I think they have a sale on them now...
MisterSandals
Participation Medalist
Roughly where are you located?
