Solar electricity...........not for your house

[chrrris]

I see even the BBC are finally feeling they have to report this situation to the masses today, several years behind those of us crazy conspiracy theorists who pay attention to such things...
BBC: Solar panels - an eco-disaster waiting to happen?

[big-all]

ok looks like a much simpler solution exactly what i want from ryobi its self
a 21w solar panel
https://uk.ryobitools.eu/garden-tools/l ... rysp21a-1/
which can feed in via a usb cable via the new ryobi inverter
https://uk.ryobitools.eu/garden-tools/l ... 8bi150b-1/
i think you can use it as both a charger to the plugged in battery via a specific usb socket from solar panels and as a powersource for usb and mains plug so fulfilling all the needs i want at least in summer months with at least enough input for a say 3ah 18v battery every day on average
at about £140 the pay back will be years but flexibility a slight smug feeling and fun to be had make it worth it

[chrrris]

Nice. That looks absolutely ideal for what you want to do. It provides a potentially very useful source of power during a power cut too - enough to charge a phone or run a radio. Very handy.

[big-all]

Nice. That looks absolutely ideal for what you want to do. It provides a potentially very useful source of power during a power cut too - enough to charge a phone or run a radio. Very handy.

yes 100% extract the maximum i think i can use
and iff all my ryobi batteries are approaching full charge
then usb charge for my phone or use area lighting for the shed the lean to or house that i am happy with already at 250/330/500/900/1200/1500 lumins that already use ryobi batteries off course mid summer a few hrs a day
now with 1000w costing around 35p a possible say 10w for perhaps 12 hrs a day in summer =120 a day so about 30p a week could pay for its self in perhaps 4 years allowing for winter blues

[aeromech3]

Just remember, ignoring efficiency/heat losses perhaps 20%, the max output of the solar is 21 watts and the battery is 221 watts hence 221 divide by 21= approx 10.5 of sunlight time.

[big-all]

Just remember, ignoring efficiency/heat losses perhaps 20%, the max output of the solar is 21 watts and the battery is 221 watts hence 221 divide by 21= approx 10.5 of sunlight time.

yes i am allowing for low ouput as in 10w for perhaps 12 hrs in the summer so120w the winter will probably 3w for 6 hrs average so 18w total
in the winter i will simply leave it idle under a polcarbon roof not at all at a decent angle but will be happy at say 10w a day total or perhaps 2% efficiency but something for no effort

[big-all]

Nice. That looks absolutely ideal for what you want to do. It provides a potentially very useful source of power during a power cut too - enough to charge a phone or run a radio. Very handy.

yes 100% extract the maximum i think i can use
and iff all my ryobi batteries are approaching full charge
then usb charge for my phone or use area lighting for the shed the lean to or house that i am happy with already at 250/330/500/900/1200/1500 lumins that already use ryobi batteries off course mid summer a few hrs a day
now with 1000w costing around 35p a possible say 10w for perhaps 12 hrs a day in summer =120 a day so about 30p a week could pay for its self in perhaps 4 years allowing for winter blues

just to give correct information i am basing on the 21w output matt
ok my 4 years pay back off course is a slight mistake forgetting to reduce the winter quarter so summer 3 months peak will exceed the 10w an hour for 12 hours a day most days the shoulders will average out a bit below the 10w an hour but for fewer hours so perhaps 90 w per day with the winter 6 months perhaps 12-20w average per day may be less so on average so perhaps only 3kw or £1 saved over the whole winter and an average 1kw a week for 6 months so 27x37p so a tenner a year so 10 to 15 years payback dependant on actual levels off generation actual electric unit costs and actual equipment costs
but as i keep saying payback is fairly irrelevant as the planet and feel good warms me far more

[chrrris]

It's an interesting experiment to perform. If you get it this month, you'll probably be, like I was last June, thinking "this is the future! So much free electricity!". Then come December you'll have real shock as solar is absolute garbage in the UK winter. Last December, I got 4.5% of the power out my setup than I'm getting at the moment. In fact, on sunny days like today, I'll generate more in one day than I got in the whole of last December. On the 16th December last year, my 720W panels provided me with a total of 20W for the whole day! You may be in a slightly better position because, at least with a small flexible panel you can easily mount it higher up and angle it down towards the horizon where the sun is in winter, which isn't easy to do for a larger setup.

Only one way to find out though...

[big-all]

there is a tree that causes a shadow for about 2 hours when the sun is low and nearly an hour in high summer mobility prevents this
there probably is no way off monitoring actual output other than by making assumptions like a 5ah 18v battery will take 26 hrs to charge at 21w so 2 whole days to charge bbbbbuuuttt a flat battery requiring 5400wm to charge fully
weeellll no several assumptions have to be made firstly a flat battery is not flat it just contains what ever amount the battery protections holds on to as a flat battery is unchangeable so lets assume 8% now down to 4948wm now on top off this the battery is perhaps 20% down on capacity so now 3974wm so should charge in around 19 actual hours assuming for simplicity its the full chaging at 21w
bbbbuuuuuttt you possible have 20% transmission and conversion losses so back up to 22hrs 40 mins to charge

anyway the point is who knows how good it will work hence my average 10w an hour for 12 hours and the six months the other side about £1/3000w 16w a day average so not worth any effort or input as no useful gain available

[big-all]

and a gteed way to save up to 40% iiiiissssss------------------------






---dont buy new new solar [or any tool]at release as within 1 to 2 years the new price premium factors out and with solar by november time sales will be poor stimulating reasonable discounts so my prediction that the £80+£100 will at some stage before febuary be anywhere between £100 and £140 the pair

[aeromech3]

There are many panels now on the second hand market such as Gumtree, I think because they are low efficiency; in this table the non commercial best, NREL in 2020, uses 140 layers of specialised materials. The average cost per watt produced for panels has dropped by about 13% over the last 10 years. SunPower and LG have good ratings.
1960: Hoffman Electric achieves 14% efficiency in PV cells
1992: University of South Florida fabricates a 15.89% efficient thin-film cell
2012: Solar Frontier reaches 17.8% efficiency
2015: First Solar breaks 18.2% efficiency
2015: SolarCity announces 22.04% efficiency and Panasonic announces 22.5% efficiency
2015: SunPower achieves 22.8% efficiency, validated by the National Renewable Energy Laboratory (NREL)
2016: NREL and Swiss Center for Electronics and Microtechnology (CSEM) achieved 29.8% efficiency
2017: U.S. scientists develop a prototype for a solar cell capable of 44.5% efficiency
2020: NREL researchers develop a six-junction III-V solar cell with 47.1% efficiency

[chrrris]

There are a few people on YouTube who've bought "broken" large solar PV panels (300W plus -- the sort that are typically used for domestic installs) that are only a few years old. It's a common fault for the diodes that are in the little plastic box on the back of them (to allow some of the cells to still generate current when other strings are in shade) to fail. Couple of quid to replace them with a soldering iron and they're good to go again. It's a good option for anyone looking to do it on the cheap, although I don't know how you go about sourcing "broken" solar panels in the UK unless you happen to know an installer or something...

[Matt.Br]

If you aren’t connecting to the grid, then the process would be easy, and you could use second-hand panels https://solarfast.co.uk/blog/second-hand-solar-panels/

You won’t be able to power much directly from the panels as they are DC and most electrical equipment, like lights and such, are AC – so you’ll need an inverter.

You can get micro-inverters that attach to panels directly.

You’d need energy storage too – a simple battery would work. Even a leisure batter from a caravan/camper.

Be careful though, unregulated Lithium-Ion batteries can be dangerous if not managed properly.