RICH SOLAR 335 watt monocrystalline solar panels

[ITman73-2]

Looking for feedback on the RICH SOLAR 335 watt monocrystalline solar panels being a good investment?

I have 2 Delta Pros for emergency use. Don’t have the room to store too many panels. 6 panels, 3 for each Pro wired in series seems to be my current solution. Ecoflow say I’ll get about 1298W (41.6V×3×10.4A) from each array.

Thanks!

 

[rmaddy]

How do you get 432W from a 335W panel? A panel's wattage is Vmp x Imp. Perhaps you are trying to multiply Voc x Isc.

3 x 335W is 1005W, not 1298W. Expect about 80% from most panels in the real world, especially in the summer when the panels are baking in the sun. So about 800W. Voc goes decreases as the temperature increases. Panel specs are at 25ºC/77ºF. I would look at the NOCT specs for the panels to see more realistic values.

 

[ITman73-2]

How do you get 432W from a 335W panel? A panel's wattage is Vmp x Imp. Perhaps you are trying to multiply Voc x Isc.

3 x 335W is 1005W, not 1298W. Expect about 80% from most panels in the real world, especially in the summer when the panels are baking in the sun. So about 800W. Voc goes decreases as the temperature increases. Panel specs are at 25ºC/77ºF. I would look at the NOCT specs for the panels to see more realistic values.

Actually Ecoflow provided the calculation (shown above) when I verified the usage.

~800w doesn’t sound sufficient when it can take 1600w (11-150w, 15A). So far 400w panels I’ve looked at seem to exceed the specs. It’s messy.

 

[rmaddy]

I'd be worried about a company selling solar panels when they don't seem to understand them at all.

What solar charge controller or all-in-one do you have? Post a link so people can review its specs and help you work out what might work for you.

 

[PhiPhi]

@ITman73-2 I think it would help if you could supply more info and the solar input specs of the delta pros. It sounded like you want to store the panels and only use in an emergency to keep the delta pros going? Also are the delta pros discrete or can they work in tandem?

 

[ITman73-2]

@rmaddy

Buy EcoFlow DELTA Pro Portable Power Station - EcoFlow

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us.ecoflow.com

Solar Charging Input: 1600W Max, 11-150V, 15A
I am in Central Florida. Normally lots of sun mixed with brief showers.

@PhiPhi
They work in tandem to provide 240v to my breaker panel through Ecoflow's double voltage hub and a generator power inlet.

I appreciate the panel advice greatly. Looking for min input of 1200w full sun each Pro, but don't have a lot of room to store panels so the fewer panels the better.

 

[rmaddy]

While the power station supports up to 150V of Voc, Voc goes up with lower temperatures. What is the coldest temperature you would ever have these panels in use? If your array Voc is 139V then you could use them down to about 32º without going over the 150V limit.

You need a combination of panels with a total Voc of 139V-140V. If you can find panels with an Isc of 7.5A or slightly lower, then you could put two strings in parallel. The number per string would depend the Voc.

Using just Rich Solar panels as examples,

The 200W ("24V" version) could be put in 3S2P for 1200W. Each has a Voc of 45.4V and an Isc of 5.83A.
The 200W ("12V" version) could be put in 5S for 1000W. Each has a Voc of 24.3V and an Isc of 10.2A
You already know the 335W panel can be put in 3S for 1005W.

You have the tedious task of looking at lots of panels from lots of manufacturers and finding the best combination.

This is like a game of tetris. You need to find the right combination of Voc and Isc that maximizes the wattage while getting as close to the Voc and Isc limits. Sadly, the 15A limit is an unfortunate limit. If it was closer to 20A you would have so many more options.

 

[ITman73-2]

While the power station supports up to 150V of Voc, Voc goes up with lower temperatures. What is the coldest temperature you would ever have these panels in use? If your array Voc is 139V then you could use them down to about 32º without going over the 150V limit.

You need a combination of panels with a total Voc of 139V-140V. If you can find panels with an Isc of 7.5A or slightly lower, then you could put two strings in parallel. The number per string would depend the Voc.

Using just Rich Solar panels as examples,

The 200W ("24V" version) could be put in 3S2P for 1200W. Each has a Voc of 45.4V and an Isc of 5.83A.
The 200W ("12V" version) could be put in 5S for 1000W. Each has a Voc of 24.3V and an Isc of 10.2A
You already know the 335W panel can be put in 3S for 1005W.

You have the tedious task of looking at lots of panels from lots of manufacturers and finding the best combination.

This is like a game of tetris. You need to find the right combination of Voc and Isc that maximizes the wattage while getting as close to the Voc and Isc limits. Sadly, the 15A limit is an unfortunate limit. If it was closer to 20A you would have so many more options.

Thank you!

I know this is a long shot but still need to ask. Is there a document somewhere or list of manufacturers to stay away from due historically poor quality or specific panels to avoid due to not meeting published energy production?

 

[ITman73-2]

@rmaddy @PhiPhi
I’m being told the below 3S2P config would work to get as close to 1200w solar input. Would like someone to check and make sure I’m not being misled. I’m in central FL and it might get to 30°F once a year. The panels are Rich Solar 200w @ https://richsolar.com/products/200-watt-solar-panel

“If you use (6) 24v 200 watt panels in series parallel using (2) sets of (3) panels this will give you 72.9V with 20amps of potential energy. If you exceed 15 amps the EcoFLow will limit the amperage to 15amp with no damage to the unit.”

“In most cases all solar panels give around 80% of the usable voltage and amperage in perfect conditions. Most of the time the amperage is lower at 6-8 amps so connecting in series parallel you'll end up at 50-60 volts and 10-18 amps. “

Thank you!

 

[BradCagle]

@rmaddy @PhiPhi
I’m being told the below 3S2P config would work to get as close to 1200w solar input. Would like someone to check and make sure I’m not being misled. I’m in central FL and it might get to 30°F once a year. The panels are Rich Solar 200w @ https://richsolar.com/products/200-watt-solar-panel

So if you series 3 of those panels you linked the Imp is 9.8a, then you parallel another series of 3 then you have 19.6a

That's over your 15a limit so no.

 

[rmaddy]

If you exceed 15 amps the EcoFLow will limit the amperage to 15amp with no damage to the unit.

This is helpful to know. But keep in mind that this does mean that this further limits the amount of power you can get from the panels.

The panels you linked in your last post are the 200W "12V" panels I mentioned in my previous post. I suggested 5 in 5S for 1000W because I didn't want to exceed the 15A limit. Putting six of them in 3S2P appears that it will work for 1200W but with the current getting clipped to 15A you can never get more than 3 x 20.4V x 15A = 918W out of 1200W of panels.

If you want to go with the 200W Rich Solar panels then I would choose the 200W "24V" versions. With those in 3S2P you get more voltage (good) and you won't hit the amp limit (good). And that arrangement should be safe down to about 17ºF.

MEGA 200 Watt Monocrystalline Solar Panel | Best 24V Panel for RVs and

The RICH SOLAR Mega 200 Watt 24 Volt Solar Pane is a key component to any solar power (PV) system. Feautures a 9 buss bar solar cell configuration and mono PERC Technology. Each solar panel includes standard solar connectors that extend from the junction box affixed to the back of each panel.

richsolar.com

Keep in mind that these Rich Solar panels are really expensive. $1/W but that does include free shipping.

You should look for local solar panel dealers where you can go pick up the panels yourself. You should be able to get panels close to $0.50/W.

Check with CED Greentech. They have a few locations in FL.

 

[ITman73-2]

@rmaddy

Thanks for pointing out my 12 vs 24 volt url confusion and confirming the 24v calcs.

Is the $0.50/W realistic for new panels?

Unfortunately CED Greentech doesn’t list any 200w panels on their site. Only 300w and greater. Still looking for others.

I’m not necessarily sold on Sun Solar. I pretty much have no starting baseline on reliable companies or well performing panels as this is my first voyage into solar backup generators. Suggestions are very welcomed. I have watched several of Will’s reviews of a few companies.

I suppose when/if I find a different panel, I’ll have to recalc with new specs. Is there a trusted online solar string calculator by any chance that takes into account all the factors?

Thanks again.

 

[rmaddy]

I bought 3 330W panels from CED Greentech in Denver about 16 months ago for $200 each. The fact that they were only 2 miles from my house then made it easy. I have no idea how prices have changed since. One thing though is the panel listings on the main CED Greentech website had little to do with what the local store had in stock. I ended up calling my local store and got a list of makes and models after giving them a wattage range I was interested in. I then looked up the specs for each panel and decided which specific panel best fit my needs. I called them back a few weeks later, ordered them, and picked them up the next day. They were helpful and easy.

Don't focus on just 200W panels. 4 300W or 4 330W (or whatever) panels could work for you with the right specs. Or maybe 3 400W panels. I suppose you have physical limitations based on where you plan to mount the panels.

Call them. See what they have. Then do your research on those panels to see if they work for you. They have 3 central FL locations. Call all of them since each may haven't different options.

Is there a trusted online solar string calculator by any chance that takes into account all the factors?

I imagine there's one somewhere but no need. It's simple math. You can probably make a simple spreadsheet where you enter the specs of one panel and the number in series and the number in parallel and you get the totals for the array.

You know you have a 150V limit. Given your location and adjusting for temperature you want to keep the total array Voc under 139.0V. So panel Voc x series count. If that's 139.0V or less you are good. You should also try to keep the Isc at 15A or less to avoid clipping (reduced output). If the panel Isc is 15A or less you are good. If the panel Isc is 7.5A or less then you can have two parallel strings. That's not too likely with larger panels.

So two simple number checks. You can go over on the 15A limit but anything over 15A is lost so the goal is to get close but not over 15A if you can.

Narrow your candidates down by panels that get you close. If you are unsure about a panel, post the details here.

Don't limit yourself to CED Greentech. There are probably lots of solar places in sunny FL.

 

[ITman73-2]

@rmaddy

Thanks again.

How are you calculating the 139.0v threshold? I’ve seen a chart from another post that suggests a different, lower value. Basically it’s the VOC x some factor, i.e., 1.1, 1.12, etc. Will attach if I can. Just trying to understand.

 

[rmaddy]

That chart gives you a rough calculation. In your case you would want the 1.1 number for 32ºF (you said that's the coldest it gets, right?).

150V / 1.1 = 136.4V so that's close to what I came up with.

It's an aiming point to help narrow down your search. Once you have a specific panel in mind then the true calculation, using the panel's actual "temperature coefficient Voc" can be used to work out the exact temperature that your array would exceed 150V. And if that temperature is warmer than your lowest possible temperature then you know the panel won't work for you.

The 139.0V value I mention is based on a somewhat typical temperature coefficient of -0.3%/ºC and being able to handle getting down to 30ºF.

The chart seems to assume a worse temperature coefficient of -0.4%/C.

 

[ITman73-2]

@rmaddy
Thank you! That helps.
Just to make sure I understand, does one rely on the NOCT specs to make the calcs for array wattage, VOC and amperage to be as realistic as possible?

 

[rmaddy]

Just to make sure I understand, does one rely on the NOCT specs to make the calcs for array wattage, VOC and amperage to be as realistic as possible?

I would use STC specs when working out whether a solar panel array can be used with a specific SCC. Just remember that Voc changes with temperature so account for that.

I would use NOCT to get a better idea of what you might really get for planning purposes.