150W monocrystalline with PWM vs 200W polycrystalline with MPPT

[Bucho]

I suspect that polycrystalline is not only ok for you but better. Polycrystalline will still give you their rated power, they're just a little bigger than more efficient technology. So it you were covering that hut in panels trying to get the most power you could then sure efficiency would matter but to you it's just throwing money away to make your panels slightly smaller.

In terms of matching a battery to this panel, would the following be okay (ie. enough Ah to ensure I'm not wasting any power and to ensure it doesn't go below 50% charge)? I had a quick check on some battery sizing calculators and it seemed to be fine, but as it's from ebay, I thought I'd double-check here to ensure the brand etc are all okay as well:

http://www.ebay.co.uk/itm/100Ah-12V-Deep-Cycle-AGM-Battery-for-Leisure-Solar-Wind-and-Off-grid-12-volt-/130982265055?pt=UK_Gadgets&hash=item1e7f26c0df

Does Wales get sun in February?

I've also found this inverter (it needs to be pure sine wave as I'm using a laptop and sound equipment with it).

http://www.tlc-direct.co.uk/Products/SK652100.html?source=adwords&kw=&gclid=CMitqo_Q7MICFYKWtAod_HEA3A

Has anyone used one of these, or if not, are you able to tell if it will be adequate?

I would think overkill. Laptops and light bulbs don't need pure sine wave, you could go much cheaper. Which would also be better for you as those pure sine wave inverters use much more power than their modified square wave equivalents.

[antobag]

Great, many thanks to both of you. I'm glad to hear that the charge controller on the 200W panel is reliable and well-known. So all-in-all, the 200W MPPT deal is a better one, even though it's polycrystalline. I'm guessing that even if the 150W panel had the same MPPT controller, the output (despite being monocrystalline) would still be much lower than the 200W panel?

In terms of matching a battery to this panel, would the following be okay (ie. enough Ah to ensure I'm not wasting any power and to ensure it doesn't go below 50% charge)? I had a quick check on some battery sizing calculators and it seemed to be fine, but as it's from ebay, I thought I'd double-check here to ensure the brand etc are all okay as well:

http://www.ebay.co.uk/itm/100Ah-12V-Deep-Cycle-AGM-Battery-for-Leisure-Solar-Wind-and-Off-grid-12-volt-/130982265055?pt=UK_Gadgets&hash=item1e7f26c0df

I've also found this inverter (it needs to be pure sine wave as I'm using a laptop and sound equipment with it).

http://www.tlc-direct.co.uk/Products/SK652100.html?source=adwords&kw=&gclid=CMitqo_Q7MICFYKWtAod_HEA3A

Has anyone used one of these, or if not, are you able to tell if it will be adequate?

Apologies for all the follow-up questions, I just want to be sure before I buy. I can go ahead and ask these questions on a separate thread if needs be.

[jony101]

i have the ecoworthy 20amp mppt controller that is showned with the 200 watt kit, so i can ascertain that it is reliable and a true mppt, i been using mine 24/7 for almost 2 years.
And i have to agree 200 watts is better than 150 watts, 2 or 3 extra amps dont sound like alot but in the solar world it is. It gets your battery charged quicker which is always good.

on my 240 watt panel with the ecoworthy mppt at most i average about 12 amps at midday but my panel is lying flat on my roof , the most I seen is 15 amps but only for a few seconds, but usually by noon the battery is already in float mode. So with 200 watts you probably get something like that or lower unless you point it at the sun. For my needs running my laptop, swamp cooler, charging my power tools, using my roadpro cooker, all my fluorescent lights its more than enough.

I think 200 watts will easily handle your needs as long as the sun is good to you.

The only thing with the ecoworthy mppt controller is that it goes from bulk, maybe spend 2 or 3 minutes in absorption then go straiqht to float. Its either in bulk or float, this has been mentioned in other forums. There is no setting for how long to keep the battery in absorption as in other high end mppt controllers. Even though it never goes to absorption it does keep my battery charged up and its the only thing thats charge the battery in 2 years. It never overcharges the battery, If the battery is full, and the sun is overhead I seen it floating at less than 1 amp.

[Sunking]

The 150 watt panel with PWM at best will supply 8 amps. The 200 watt panel with MPPT at best will supply 17 amps or more than twice the power on the output.

[antobag]

I am completely new to solar power and I am considering buying a solar panel system for an off-grid hut in Wales, where I will be staying during the month of February. I require roughly 100 to 200 daily Watt-hours to power an LED light and a laptop on which I will be working. I have found two solar panels on ebay that seem to fit my needs, but as I have zero experience in buying solar panels, I thought I'd ask here before going ahead with the purchase.

Here are the two panels:

http://www.ebay.co.uk/itm/150W-solar-panel-kit-folding-monocrystalline-battery-charger-150W-caravan-12v-/301459750815?pt=UK_Gadgets&hash=item463066bf9f

http://www.ebay.co.uk/itm/2-100Watt-solar-panel-W-20A-MPPT-complete-Kit-for-RV-Boat-Home-System-12V-24V/390980292475?_trksid=p2047675.c100009.m1982&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D28111%26meid%3D018cd0a05ec24dbf876daf13696ac444%26pid%3D100009%26prg%3D11472%26rk%3D8%26rkt%3D10%26sd%3D301459750815

My main question is: Would it be better to buy the 150W monocrystalline panel with its included PWM charge controller, or the 200W polycrystalline panel with its MPPT charge controller? (Both controllers are rated at 20Ah). I know that monocrystalline panels are slightly more efficient, but I assume the extra 50W of panel would counter this. I've also heard that MPPT charge controllers are more efficient in systems of 150W and higher, and also in cold conditions (I will be using the panel in British winter at a reasonably high altitude). Taking this into consideration, which panel would be more suitable?

Any help would be much appreciated.

Antony