Comparing/rating solar brands

[kVox42]

I know there's plenty of good info on the forum regarding solar options. I'm wondering if anyone has experience across various manufacturers in terms of their quality? For those considering a solar panel to provide - or supplement - their power needs, it starts of course with figuring out how much power you need, how often you'll be in the sun, where you want to mount it, how portable and/or permanent you want it to be mounted, getting the proper controller, and several other factors.

I'm deciding on those factors for myself since I'll be adding some supplemental power on my TD, (which is finally nearing completion - woo-hoo!!!) I'll need a reasonably small unit and capacity (around 100 watts, give or take 50). I also want mine to be fairly portable so I have flexibility. I'm wondering about the quality differences between some of the brand names I'm coming across. Everyone SAYS they make a great product, but proof is in their real life performance. Some of the names I've come across are:

Renogy, Go Power, Zamp, Grape Solar, PowerFilm Solar, SatStation Solar Flex, Goal Zero, and others.

Anyone have any experience in the "solar" business who could offer some tips to help us all?

Kevin
Raleigh, NC

[MtnDon]

Are you considering what are known as "12 volt" panels, along with a PWM charge controller? Have a look at the panels offered by SolarBlvd.com

Or if you are considering higher voltage panels with an MPPT controller check with local residential solar installers. Some are willing to sell you a single panel if they carry stock. Where I am I can do that and save of the freight costs.

[ukewarrior]

In reality, there are only a few folks that make the cells for panels and then only a slightly larger group that makes completed panels.

My wife was the COO of a Solar Installation company that built mega-watt power stations.
They bought purely on price and ability to deliver. Plain and simple.

I'd be most concerned about the controller you buy. There is the largest variance in that all important device than there is between the different panels.
However, if you really want to get to a ranking in terms of panel quality, I'd go buy where it's made.
My ranking:
1. Japan
2. USA
3. Germany
4. Taiwan
5. China

On another note, I made a 70Watt setup for my daughters tear from two 35W panels that I mounted together with a hinge.
It's very portable and small sized.

[GPW]

Kevin , I’m with you and would like to know !!! There seems to be a lot of confusion out there ( I know I’m confused ) about what to get , how big to get , and what it will power ... The new technology further expands the market choices , therefore becoming even More confusing We just need some good solid facts about what works for other people and what doesn’t and how much it costs ... as some "cheaper alternatives" (HF) actually turns out to be less thrifty per watt ...
And now all I can think about is the flexible Solar cell films that could perhaps be mounted to a trailer top ...

[tony.latham]

There seems to be a lot of confusion out there ( I know I’m confused ) about what to get , how big to get , and what it will power

The first thing you need to do is figure out your energy consumption. Until that's done, it'll remain an enigma.

I built a folding sixty watt system that hasn't seen sunlight all summer. Just haven't needed it. We use the Fantastic fan for an hour or two and an LED for a bit. No refrigerator and of course no air conditioner (thank goodness we don't need one where we camp in Idaho and Montana). I've got a 20 watt panel that's on the tongue box and as long as we're in the sun, that's enough. This fall when we start preheating our bed with the 12V blanket for 45 minutes, I might have to pull the 60 watter out.



Pre-20 watt:



I too think it's all about price. I have yet to see a logo on solar panel.

Tony

[GPW]

Ton’, the problem is I really don’t know what I’ll need and have to give that some thought ... I’d like a reasonably portable system we could use in the FoamStream and also use at the house when the power goes out ... The thought of something big enough for a small AC and dorm fridge would be more than ideal , but I’m afraid that would not be as portable ... and require some serious batteries /converters. I’m not ready to commit to whole house Solar/grid as my neighbors have done ...

The Harbor freight 45 watt kit (3 - 15watt panels ) seems a little “lightweight” for my purposes ... That’s watt I have now ...

[felixx]

I have 3 x 3w LED clusters in my 8x4, this equates to .75A
1 have a 1w red LED nightlight for my kids too (0.08W)
I have 2 x 3W lights in my hatch (0.5W)

So with all my lights = 1.3A (Approx)

Charge my phone = 0.5A
My fan is solar powered with it's own battery

So with everything running I MIGHT use 2A (24AH)
IF this is on for 8H I might use use 16AH of electricity (very unlikely to do this as I have small kids so lighting will not be on long

a 50W provides 4.2A (approx)

This is DOUBLE my output so therotetically my battery would be topped up within 4H of good sunlight
a 75W would do this in 3 hours (assuming my battery liked 6A pumping into it)


I dunno what you are using current wise but that will answer your question

I am waiting for a cheapish panel (pref flexible) of 50 or 75W

(I am in New Zealand)

[ukewarrior]

I forgot to mention that I built the 70W folding array from ebay purchased panels for under $100.
This is enough to charge one decent battery and run a lot of LEDs and fans and a radio without needing to recharge every day.

[booyah]

I haven't built out my solar, but its in the plan. Just got postponed by "Central Accounting" as she objected to that line item for this year. In my case is a 100w "bendable" panel, with a 10a PWM charge controller grand total about $300 after cables, fuses etc.

So I have a nice little calculator for these things that I made in excel when I was looking at building an off grid cabin... Because of that I'm going to gloss over the math behind it all, but it figures in things like your latitude, your areas yearly usable solar hour average, panel de-rating, charging system de-rating, ideal charge rates, etc.

So, for load--
My loads
Fantastic Fan (1.35a draw at low setting)
Two MR16 style LED lights (.26a draw each)
Two array LED porch lights (.16a draw each)
Two chargers for phones, tablets and other electronics ( at 95% efficiency (dc-dc conversion) lets say .92a draw charging one device each)

So figure if everything were left on, doing everything I'm drawing 4.03 amps an hour (48.36 watts because watts are watts no matter watt).
So if everything ran all day every day it would draw nearly 100 amps (1200 watts) in a 24 hour day.
Mind you that is totally unrealistic.

Now, in a much more realistic load lets say I charge one phone for an hour, one tablet for 4 hours, run the outside lights for about 1 hour a night, and the inside ones for about 4 and run the fan for 8 hours (sleep). Now we're talking about 17.8 amp draw. (213.6 watts).

Storage/Battery--
Based on that, I chose a group 24 deep cycle battery. Its rated at 75 amps, or really about 60 usable (in a pinch 80% discharge). At that type of load I will draw my battery down 80% in 3.37 days, 50% in about 2.1 days, or 30% in 1.26.

Since this is a fair weather camper anyways, and I'm unlikely to be totally without power options (small generator, car, campground/shore power etc) I'm OK with that 75ah battery. If I weren't, a group 31 (115ah) would put me at 5.1, 3.2, and 1.9 days for those same load outs.

So load is covered, storage is covered, now lets look at solar charge.--
Ideal usable charge rate is about 10%, max usable is about 13%, and cycle (just enough) is about .05%. In my case I opted to shoot for between max usable and usable, (so about 11.5%)

Figure in a bunch of math, ideal angles, derating, charging inefficiencies, etc, and a 75 watt panel would be right for "ideal usage" for my uses.
In my case, figure a fair amount of partial shade, non ideal angles, my tendancy to overdo things, and you get a 100w panel to more than offset my entire load in the average solar day. In summer we're nearly double "average", so that factors more in my favor.

All of this is why its not so simple, there are some forums that will greatly help you
These guys are your buddies, they know their stuff backwards, forwards and inside out.
http://forum.solar-electric.com/forum

[tony.latham]

Booyah:

It sounds like you've been cogitating on this long and hard. My useage is similar. Here's a pic of my 20 watt panel:



I installed it in late May. There's a Morningstar SungGuard controller in the box. We do a fair number of one, two, and three nighters. I think we're probably pushing twenty-five nights in the 'drop for this summer. The 60 Watt foldable is in the box:



And guess what? We haven't had a need for the sixty-watter this summer. Since we're charging from the TV while on the road, the battery is topped off when we get to our camp spot. If the battery is down a bit from the trip, it gets topped off by the time we're home. The cool thing about the panel on the lid, is it's always maintaining the battery. This winter It'll chug away...

I too picked up my two thirty-watt panels off of eBay for around $100 for the set. Solarblvd sells that 20 watt panel for $32.

Solar power is cheap. I keep looking for a graphic of a generator with crosshairs on it but haven't found one yet.

Tony

[Midget]

We picked up the 45w system from Harbor Freight last year. I don't like it at all. The panels are very heavy and difficult to store for travelling. Their 45w rating must be off as it won't recharge the battery very well.

Four our new build we picked up an 80w panel with MPPT controller from Renogy. I plan to mount the panel to the roof just behind the fan. Always charging the battery even when we're travelling. The new build will be all LED lighting with a fantastic vent and inverter so my wife still has her curling iron even when dry camping.

Bob

[Esteban]

Grape Solar 160 watt panels have recently come back in stock after being unavailable for months. So I just bought one!.

I'm going to permanently mount the solar panel to the roof of my 64" wide teardrop with Instapark Drill-free Mounts. I bought the white version of the Instapark glue-on mounts.

I'll have three ways to power my teardrop's battery. 1) solar power. 2) shore power when available. 3) power from my tow vehicle while towing my teardrop.

160 watts may be more power than I usually need. It provides a fudge factor for overcoming less than optimal camping and solar harvesting conditions. I plan to use all LED lights and a Fantastic Vent which do not use a lot of power. The biggest need for power will be an AC/DC chest type fridge freezer in the galley. I'll use a mppt solar controller to harvest as much power as possible from the solar panel, instead of a less efficient pwm solar controller.

I want to be able to boondock camp without a need for shore power. With solar power I can also save money by not needing to pay for more expensive campsites with electric hookups.

The Renogy 150 watt solar panel was another contender. But it is too big (39.5 X 39 X 1.4 In) for the available space on my roof. It might work for other people's teardrops.

Some other choices might be the Solar Cynergy 120 Watt 12 Volt Solar Panel or the Solar Cynergy 100 Watt 12 Volt Solar Panel
from Solarblvd.com.

[booyah]

Booyah:

It sounds like you've been cogitating on this long and hard. My useage is similar. Here's a pic of my 20 watt panel:



I installed it in late May. There's a Morningstar SungGuard controller in the box. We do a fair number of one, two, and three nighters. I think we're probably pushing twenty-five nights in the 'drop for this summer. The 60 Watt foldable is in the box:



And guess what? We haven't had a need for the sixty-watter this summer. Since we're charging from the TV while on the road, the battery is topped off when we get to our camp spot. If the battery is down a bit from the trip, it gets topped off by the time we're home. The cool thing about the panel on the lid, is it's always maintaining the battery. This winter It'll chug away...

I too picked up my two thirty-watt panels off of eBay for around $100 for the set. Solarblvd sells that 20 watt panel for $32.

Solar power is cheap. I keep looking for a graphic of a generator with crosshairs on it but haven't found one yet.

Tony

Yeah, for some reason I'm not a fan of the idea of charging off the tow vehicle. I understand lots of folks do it, I just dont like the concept. Totally my bias here, so of course your milage may vary.

My goal is a 100% self sustained tear, that can do what I want, when I want, where I want, pulled by whatever vehicle I want

Thats why the solar is such a big deal to me, as well as sustainable water (gravity filter).

I know, not asking for much am I?

[felixx]

I like your train of thought..
I considered charging off the TV but decided against it.
My main TV is a work (Leased) vehicle I cannot modify

I will be running solar to make it self sufficient.

I like the concept of parking it on tent sites (CHEAP) in camp grounds

[DrewsBrews]

So figure if everything were left on, doing everything I'm drawing 4.03 amps an hour (48.36 watts because watts are watts no matter watt).
So if everything ran all day every day it would draw nearly 100 amps (1200 watts) in a 24 hour day.
Mind you that is totally unrealistic.

Now, in a much more realistic load lets say I charge one phone for an hour, one tablet for 4 hours, run the outside lights for about 1 hour a night, and the inside ones for about 4 and run the fan for 8 hours (sleep). Now we're talking about 17.8 amp draw. (213.6 watts).

I suppose you mean Amp-hours and Watt-hours?