lensun flexible solar panel - report

[contessaman]

Just took delivery of an ebay 60 watt flexible solar panel. £220 delivered.

construction appears reasonable for the money. aluminium sheet, coated in tedlar, cells laid on that then more tedlar. wiring looks a bit fragile will have to beef it up.

tests so far on a bright winters day with a watery sun low on the horizon:

midday angled panel towards sun: 20.1 volts, 2.1A
laid flat: 19.9 Volts, 0.8A

first light in the morning, sun below horizon
19 volts, 0.25 A

dark overcast day 18.5 Volts, 0.2 A angle makes little difference.

Its quite sensitive to shadow -even covering a small area of the panel causes a substantial loss in current so I will need to park the boom over to one side (going to mount it on top of deck saloon).

I suppose the quoted power is in the middle of a nevada salt lake at midday so the figres arent too bad.

Hopefully these figures are of use to potential purchasers, be interested to hear how your more expensive panels perform.

 

[ianj99]

Thanks for the feedback. Real life reports are always worth having as opposed to the armchair 'experts' comments.

If you are on the west coast, I think a wind generator more appropriate for all year round use! (The sun has tended to taunt us with brief appearances for the last couple of years)

Ian

 

[VicS]

You do not say how the panel was loaded while you took the readings.

The voltages you quote are close to what one would expect for an open circuit condition, ie no load yet you quote them next to current readings.
Clearly you could have got much more current that you quote by increasing the load

It would perhaps be more useful to load the panel until the terminal volts is equal to the volts, which should be quoted in the literature, for maximum power output and then record the current produced under those conditions.

Otherwise, perhaps even better, take readings at different loads to determine the figures corresponding to maximum power output under the different conditions.

 

[contessaman]

Thanks for the feedback. Real life reports are always worth having as opposed to the armchair 'experts' comments.

If you are on the west coast, I think a wind generator more appropriate for all year round use! (The sun has tended to taunt us with brief appearances for the last couple of years)

Ian

yep, my father has just given me his aero2gen. its an old model but like new condition, so hopefully that will go hand in hand with the solar to keep me all topped up!

 

[contessaman]

You do not say how the panel was loaded while you took the readings.

The voltages you quote are close to what one would expect for an open circuit condition, ie no load yet you quote them next to current readings.
Clearly you could have got much more current that you quote by increasing the load

It would perhaps be more useful to load the panel until the terminal volts is equal to the volts, which should be quoted in the literature, for maximum power output and then record the current produced under those conditions.

Otherwise, perhaps even better, take readings at different loads to determine the figures corresponding to maximum power output under the different conditions.

sorry, forgot to say current readings were short cct thru a multimeter. voltages were open cct off load. To my mind as long as Vpanel is more than Vbattery then current will flow. short cct current will give a indication (albeit optimistic) as to the output into a flat battery or a battery under load whilst sailing.

 

[VicS]

sorry, forgot to say current readings were short cct thru a multimeter. voltages were open cct off load. To my mind as long as Vpanel is more than Vbattery then current will flow. short cct current will give a indication (albeit optimistic) as to the output into a flat battery or a battery under load whilst sailing.

Thanks for clarifying.
Once one knows how the measurements were made one can make comparisons.

 

[V1701]

Yes I have a Lensun 40w semi-flexible panel, it's fine apart from, as you say, the wiring being not that substantial. I put a big blob of CT1 around where the wires leave the diode for extra strength/waterproofing. The panel stays out in all weathers and has survived since April with no problems and no evidence of degradation. I reckon it's not bad value for money, though the ally framed ones are better value...

 

[contessaman]

Yes I have a Lensun 40w semi-flexible panel, it's fine apart from, as you say, the wiring being not that substantial. I put a big blob of CT1 around where the wires leave the diode for extra strength/waterproofing. The panel stays out in all weathers and has survived since April with no problems and no evidence of degradation. I reckon it's not bad value for money, though the ally framed ones are better value...

good to hear it. Im going to stick my panel to the coachroof with CT1. my coachroof is quite curved so I had to go for the more expensive flexible (££'s per watt) option otherwise I would have had the weight, eyesore and windage of wooden/metal brackets either side.

Having finally got my hands on a yacht thats in her gleaming original gelcoat (after several painted boats) im loath to make any more holes in it than I have to!

way I see it, stick the cheapo panel down with mastic, one hole for a cable gland, then when it inevitably fails I can just peel it off and throw it in the skip, then piggle off the mastic.

I am going to reinforce that black diode box with epoxy, then get some black mains flex, withdraw the brown and blue wires from the black outer and feed the supplied red/black figure 8 through it. that way I'll be double insulated, and the round overall cable will seal in a cable gland.

FWIW I'll stick some photos on here with what I have come up with when im done. Doubt I'll get round to it for a few months though! isnt work a drag!