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RE: The best photovoltaic solar panels
The model is HIT-220A01.
For those interested Wholsale Solars price is $715.00
VMP 72.7
IMP 5.17
Cell efficiency 19.8
Module efficienct 17.4
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harold1946
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05/03/13 06:43am |
Tech Issues
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RE: The best photovoltaic solar panels
Are you talking about their temperature performance?
Temperature Performance
"As temperatures rise, HIT Power solar panels produce 10% or more electricity (kWh) than conventional crystalline silicon solar panels at the same temperature."
Looking at their spec, their temperature coefficient for Voc is not good (-0.142V/C). My Kyrocera panel has a better spec than that (-0.082V/C).
I don't understand how they get better efficiency at higher temp.
Sal
One of the unique features is that their efficiency increases as surrounding temperatures rise, where most will loose.
I believe what they are saying is that do not drop off as temperatures rise as most panels do. Some as much as 60%.
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harold1946
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05/02/13 09:56pm |
Tech Issues
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RE: The best photovoltaic solar panels
"The topic is about advances in the efficiency of PV. Nothing to do with amp out-put or charging batteries. Simply that this is the most advanced PV panels available as to efficiency"
If the efficiency of the panels has nothing to do with their relative abilities at charging batteries (making amps), then we are not living on the same planet or even in the same "solar" system :)
I do not know how to explain efficiency any better. Sorry!!!
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harold1946
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05/02/13 09:49pm |
Tech Issues
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RE: The best photovoltaic solar panels
Hi,
That 29% figure is in the cold vacuum of space. Heck, I can't even get my RV to float, let alone be gas tight for LEO. *grin*
Are you sure ?
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harold1946
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05/02/13 09:43pm |
Tech Issues
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RE: The best photovoltaic solar panels
i belive the 'efficency' he is talking about
is amount of power converted to electricity from the , the sq meters/ft of surface area at std irradiance tests
Ok, the 230w, 7.63a Imp panel is 39.38 by 65 inches. = 2560 sq in
the "efficient" 220w, 5.6a (Imp?) panel is 31.4 by 62.2 inches.= 1953 sq in.
So to be as "efficient" for watts as the 220 the 230 would be 230/220 x 1953 = 2042 sq in instead of its 2560 sq in, so that is fine.
The amps per sq ft gets you 5.65 and 1953 so 7.29 would be
7.29/5.65 x 1953 = 2520 sq ft vs the real 2560 for the 230w Sun panel
So no big diff there. That means it is all down to the MPPT controller what really happens between the two panels for their 'efficiencies" in charging batteries (producing amps)
Watts are nice, but it is amps that charge the battery. Will an MPPT sort out the amps to "Make up" the 7.29 vs 5.65 "little problem" here?
The topic is about advances in the efficiency of PV. Nothing to do with amp out-put or charging batteries. Simply that this is the most advanced PV panels available as to efficiency.
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harold1946
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05/02/13 09:29pm |
Tech Issues
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RE: The best photovoltaic solar panels
Pretty interesting. New world records are being set weekly for solar output per area. It is nice to see this making it into actual products.
Jim
Maybe one day we will have some of the technology that is available to NASA, 29% efficient from what I have heard.
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harold1946
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05/02/13 09:11pm |
Tech Issues
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RE: The best photovoltaic solar panels
Thought I would share some information on what are rated as the best/most efficient panels available.
Sanyo HIT Power N Series.
The cells are hybrids of monocrystalline silicone, surrounded by ultra-thin amorphous silicone layers. It is unique to Sanyo.
Panels are 31.4 by 62.2 inches, generate 220 watts at 5.65 amps, and have a cell efficiency of 19.8 percent.
One of the unique features is that their efficiency increases as surrounding temperatures rise, where most will loose.
They are made in California and Oregon.
Good info. But isn't it interesting how we've exported all our technology overseas?
I am not sure where this technology was developed. :@
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harold1946
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05/02/13 09:03pm |
Tech Issues
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RE: The best photovoltaic solar panels
i belive the 'efficency' he is talking about
is amount of power converted to electricity from the , the sq meters/ft of surface area at std irradiance tests
Yes; the standard for rating all PV.:)
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harold1946
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05/02/13 08:48pm |
Tech Issues
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RE: The best photovoltaic solar panels
Please explain why 220 at 5.56 (Imp?) is better than 190w at 5.28 Imp or 230w at 7.63 Imp
In fact 220/230 x 7.63 = 7.29 That is way more than 5.56.
Please define "efficiency" as you understand it, because I sure don't get it in terms of amps output.
Unfortunately, we are also into MPPT which has its own amps-making protocals, that distort all rational thinking. :)
http://www.windturbine.ca/sun_panels.html
Has nothing to do with amps.
efficiency: The ratio of energy developed by a machine, engine, etc., to the energy supplied to it, usually expressed as a percentage. In this case 19.8%.
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harold1946
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05/02/13 08:38pm |
Tech Issues
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The best photovoltaic solar panels
Thought I would share some information on what are rated as the best/most efficient panels available.
Sanyo HIT Power N Series.
The cells are hybrids of monocrystalline silicone, surrounded by ultra-thin amorphous silicone layers. It is unique to Sanyo.
Panels are 31.4 by 62.2 inches, generate 220 watts at 5.65 amps, and have a cell efficiency of 19.8 percent.
One of the unique features is that their efficiency increases as surrounding temperatures rise, where most will loose.
They are made in California and Oregon.
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harold1946
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05/02/13 07:55pm |
Tech Issues
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RE: Rubber Roof
I use Murphys oil soap to wash and 303 protectant.
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harold1946
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05/02/13 05:16am |
Toy Haulers
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RE: best low light performance
I have heard many claims over the years about this or that panel being superior, but the fact remains, if one is using more than can be produced, the only answer is to produce more, and the answer to that is an array that will produce the most power with the available realestate.
I basically agree, but my take would be *enough* power *under the actual conditions the solar panels are in*. Or possibly under the worst case conditions you care to plan for.
That seems to be the difference in the approach. Design for specific conditions that are different than nominal, or select technology for nominal conditions and just keep getting more until it meets your actual conditions often enough.
Jim
I guess we could go with different climatic scenarios, but what would be the point. I believe everyone would agree that solar is not without its shortcommings, and under extreme conditions can be taxed passed its capability.
My AGS system kicks in the genny whenever the solar is not able to handle the load.
We are fulltimers, not weekenders. We go where we choose from Mexico to Alaska, east or west coast. If it snows I have to clean off the solar panels. Over 90% of the time we are boondocking. Between March and November of last year we spent two days with hookups.
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harold1946
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05/01/13 03:37pm |
Tech Issues
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RE: best low light performance
Harold
I've asked nothing of PT, if the man says he gets those numbers, I have no reason to question him. I would also be thrilled to get those amps in low light. I know I live in "sunny Colorado" but I've seen plenty of overcast days here while camping. Especially in the spring and fall when we need the amps to run the furnace at night.
My concept is meet your needs in low light and you will always be happy, meet your needs in only bright light and one day you will meet my lil friend... Mr Generator.
BTW
The question was asked of you, not PT. You were the one that side stepped it, PT has been upfront with real world experience. You have only dismissed or discredited anything that doesn't support your position.
So here is a different question of the real world for you. What kind of amps do you get in shade or sun blotting out overcast and yes even in the rain? How long can your batteries last in those situations before you find a alternate means of charging? A week? Two weeks?
When you give the answer please add how many watts, how many AH and daily use.
Thanks
I will do the best I can.
Battery bank AH 735.
860 watts of solar.
I do not bother calculating our daily use, never found a need to.
The amount of amps being produced it totally dependent upon the amount of sunlight, not the amount of shade, and I do not have a means of measuring shade.
If I am not using any power the battery bank only looses at a rate of 1% per month. Otherwise the length of time varies greatly depending on power consunption.
I did not side step the question, I can not answer for what PT claims. Only he can answer that.
It is 12:55 right now and my array is producing 30.43 amps in full sun.
I have also seen days when the best being produced was 3 amps.
Solar charging batteries is like filling a bucket with a hose. A firehose will fill it faster than a garden hose. If water is being used out of the bucket it takes a bigger hose to keep it full.
I have heard many claims over the years about this or that panel being superior, but the fact remains, if one is using more than can be produced, the only answer is to produce more, and the answer to that is an array that will produce the most power with the available realestate.
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harold1946
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05/01/13 02:49pm |
Tech Issues
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RE: best low light performance
JiminDenver:
Seems you are not going to get an answer from pianotuna. I have made requests of him to support his claims several times to no avail.
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harold1946
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05/01/13 12:21pm |
Tech Issues
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RE: best low light performance
Hi,
Misleading information, panels intended for charging a 12 volt battery are never 12 volts. Very optimistic numbers. Even worse if pwm is used. MPPT has conversion losses of between 2 and 4%, and losses increase as input voltage rises.
Watts = amps x volts. cant have one without the other.
a 12 volt, 256 watt panel is capable of producing 21.3333 amps maximum.
12 volt, 460 watts will produce 38.3333 amps maximum.
How is it misleading? the formula is the same, just change the volts to Unisolars spec of 16.5 volts and calculate for 256 watts.
256/16.5 = 15.5151 amps maximum. at peak output. Or what ever voltage trips your trigger.
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harold1946
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05/01/13 05:19am |
Tech Issues
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RE: best low light performance
Watts = amps x volts. cant have one without the other.
a 12 volt, 256 watt panel is capable of producing 21.3333 amps maximum.
12 volt, 460 watts will produce 38.3333 amps maximum.
So then what's your explanation as to how Tuna can get more amps in the shade and rain than I can with near close to 200 watts more in my panels combined?
I will let Tuna explain how he can get more amps from a grid than it is designed to produce.
US-64 specs are 16.5 volt. output
So using the total wattage of the grid (256 watts)we calculate amps= watts / volts.
256/16.5 = 15.5151 amps.
As you can see, as the voltage increases the output amps decrease.
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harold1946
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05/01/13 04:55am |
Tech Issues
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RE: best low light performance
Watts = amps x volts. cant have one without the other.
a 12 volt, 256 watt panel is capable of producing 21.3333 amps maximum.
12 volt, 460 watts will produce 38.3333 amps maximum.
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harold1946
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04/30/13 09:27pm |
Tech Issues
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RE: best low light performance
2x230 watts = 460 watts, which would give 195 watts more than 256.
2x 128 watts = 256 watts.
A 256 watt panel produces 256 watts at its peak output, no more.
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harold1946
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04/30/13 08:37pm |
Tech Issues
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RE: best low light performance
My effort of a question was simply to establish a basic formula for one square micron or a billion square miles of panel area.
Would it matter if my 130W 32x43" panel were expanded to 32x42 light years and the Unisolar expanded proportionally?
Ignoring that the panels may need to use insolation from different stars, why would the ratios change?
HTH;
John
It all becomes more relevent if the flux capacitor is quantified and equalized through the isolating and proportioning azimuth.
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harold1946
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04/30/13 05:47pm |
Tech Issues
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RE: Bearing Seals
Either one will work. The doudle-lip that is used on boat trailers are designed to keep lake water from being sucked into the bearings when submerged.
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harold1946
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04/30/13 12:10pm |
Travel Trailers
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