Solar-powered garden lights indoors?

[FrodoOne]

I thought I was going to see some useful suggestions, however all I see is the products or components of products sold in poundshops.

I think John has been making it abundantly clear he is expecting to use a bigger solar panel and bigger battery, in some way, to achieve the required goal

And I wrote suggesting components to which more "Panels" and Cells could be added.

(Also, the source I mentioned is likely to be much cheaper than "Pound Shops" - if one can accept the "Delivery" delay.)

I would doubt if you could find these items (which I have used) in "Pound Shops"
https://www.aliexpress.com/item/100...order_list.order_list_main.279.2e151802a1nSWG

 

[ebee]

It would be interesting to see what John comes up with at the end of his research, indeed it would be interesting to see what other contributors have come up with too.
It might prove to be of some guidance for others, no doubt we could learn some similarities and some differences, all food for thought for anyone embarking on use of such things and adding to collective knowledge.

Whether there is any truth in the legend of someone thinking "Hey, what has just pulled that apple down to my head?" or "What time does Huddersfield get to this train?" or not, every bit of knowledge helps the big picture for future users.
Even incorrect ideas followed by many will eventually lead us to establish we have been following a "Red Haddock" - I was told some years ago that the world before computers got it wrong about the way to use and store data by following analogue rather than digital, which seemed to be very logical at that time but potentially put us back for many years in comparison.
Another "Legend " I heard was that Barnes Wallis set his teams the task to prove that XXXX was impossible to achieve, once all do, the next task was to achieve XXXX, true or not? food for thought anyway.

So, let`s see how things progress, it is exciting.

 

[Harry Bloomfield]

Avril, a couple of years ago, bought one of these- https://www.amazon.co.uk/Security-W...eywords=Solar+PIR+Light&qid=1721289022&sr=8-5

When triggered, and even in winter, it chucks a surprising amount of light out. It's mounted on the side of the hut, facing south/east, behind the house, and so only catches the morning sun. It's a fairly enclosed area, so not often triggered, but it always self triggers once at dusk - maybe to confirm it is working?

 

[JohnW2]

OK. ... I was trying to be helpful in "designing" a small "system" which could be expanded - using more "panels" and more/larger capacity Cells ...
while the input is (nominally) 2 V, the output is 3 V - using one (or more) 1.2 V Ni-MH Cell(s).

Fair enough.

I really don't think that any sensible future lies with the use of any of these cheapo garden toys - I'm merely using them for conceptual experiments. I very much doubt that (no matter how much battery storage capacity one provided) any of these products have adequate solar panels for use indoors (and certainly not when days are short). Furthermore, they all seem to work at very low voltages, which would seriously frustrate (if not preclude) my designing of 'control systems' etc. I've far more likely to end upsystems using at least 5V, if not 9V or 12V.

 

[JohnW2]

Avril, a couple of years ago, bought one of these- https://www.amazon.co.uk/Security-Waterproof-Outdoor-Powered-Outside/dp/B09M8FYTXT/ref=sr_1_5?dib=eyJ2IjoiMSJ9.GRNwpP2DJy3SKXF65A9TGfqqdZLWi6TXn_q75l31B9jqdeuYzTY-dMCt5j__CzQ8ze85dkGEZhjPOGSYeVnTnEtX0AvZbuSPpVJ1PzAxsAFoUWp7pFD8k9MqB0iqkGqgatarSqn01eaCqW7uyEeWFKvFwGI5DNqTnAe5zcNMfkDBkBcq1C3-vwdHRiGGjc4joVwwkqRgpEyL5m8u7z38g5rhxdIa-Gwj4YYQzuddSj7GRrjvW_nU1mS07VTebnZnjfd6lwy7McdUtKNuYbkJg6cX0BqvMXPB0mLW9GoODZg.ArHTdtKk5_-tY9Pg_5x1baO8NvuRiSVkrTbWUOUBZMY&dib_tag=se&keywords=Solar+PIR+Light&qid=1721289022&sr=8-5 ] (link) [/url] ....
When triggered, and even in winter, it chucks a surprising amount of light out. It's mounted on the side of the hut, facing south/east, behind the house, and so only catches the morning sun. It's a fairly enclosed area, so not often triggered, but it always self triggers once at dusk - maybe to confirm it is working?

Thanks. Yes, I know a good few people who have things like that and, as per your experiences, report that they work well, even during Winter, and seem to last pretty well.

However, there is clearly one very big difference between them and what I want to achieve. A PIR-activated solar light will usually only have to come on for a small number of minutes, if at all, each night - whereas I want continuous illumination for at least a few hours every night. Couple that with the fact that the solar generation will presumably be appreciably (perhaps considerably) inferior when housed indoors, and the jump between these outdoor PIR-activated solar lights and what I want/need is a very ig one.

 

[Harry Bloomfield]

Furthermore, they all seem to work at very low voltages, which would seriously frustrate (if not preclude) my designing of 'control systems' etc. I've far more likely to end upsystems using at least 5V, if not 9V or 12V.

Volts drop, when such low voltages are involved, is quite a problem. My weather station, transmits its data every minute, using a pair of AA cells for power, and they tend to last a year or two, before needing replacement. As the transmitter is up a pole, it involves getting a ladder out. After a few times of doing this, I decided to run a two core, telephone extension, down the mast, then to a double 2x AA cell holder - Two pairs, in parallel, and easy to access, on a shelf in my workshop..

That allowed me to swap out one pair of batteries, followed by the other, without the station having to go through the long reboot process. The problem I hit, was volts drop, but only during the brief higher power demand of data transmission pulse. I solved that, by adding a capacitor at the transmitter.

 

[JohnW2]

It would be interesting to see what John comes up with at the end of his research, indeed it would be interesting to see what other contributors have come up with too. It might prove to be of some guidance for others, no doubt we could learn some similarities and some differences, all food for thought for anyone embarking on use of such things and adding to collective knowledge.

There was never really the need for much empirical 'research'. Solar panels of almost any shape, size, generating capacity and voltage output are readily available, as are batteries of any voltage/capacity and a wide range of LED light sources. It would therefore have "almost" been possible for me to design a system to suit my requirements purely on a purely theoretical basis, using off-the-shelf components.

As for that "almost", the one unknown (at least as far as I was concerned) was the likely performance of any of the available solar panels when used 'indoors' (i.e.receiving light through a window), and that is what my experiments have been, and will be, all about.

I have now established, qualitatively, that the concept of using a solar panel indoors is seemingly viable, and I also know roughly how much electrical energy I would ideally like to generate each day. It therefore remains for me to guess (on the basis of itsclaimed performance when used outdoors) how big a solar panel I might need, and then to try such a panel indoors and find out what I can actually achieve. I may or may not'get that right' (try a large enough panel) first time - watch this space

Kind Regards, John

 

[JohnW2]

Volts drop, when such low voltages are involved, is quite a problem.

Yes,I suppose that's another potential issue, although I don't envisage the need for conductors of significant length (and could use fairly large CSA ones if I had to).

However, more to the point, to attempt to produce electronic 'control systems' with a 'supply rail' of only 1.2V (or even 2.4V) would be a serious challenge, if possible at all - hence my plan to probably use an appreciably hogherd voltage than that.

 

[ebee]

have now established, qualitatively, that the concept of using a solar panel indoors is seemingly viable, and I also know roughly how much electrical energy I would ideally like to generate each day.

Yes, that is what I thought you had intended.
I rightly or wrongly wondered if you had planned to cover a few places where light not be as intense and for less duration as part of a future plan to realise the best to worst sort of scenario and the ratio betwixt such.
After all, with any system we would always pick the best locations but in many instances due to what we have before us we might have to consider second, third, fourth best etc right down to the line as to consideration of economics and practicalities and the worthwhile/not extent of any permissible designs.
Not everybody has a blank sheet to start off designs with and compromise using sense is often required. Mitigation is sometimes key.

 

[Munroast]

I have toyed with that idea, but as yet have given it little thought, since I have almost no experience of wind turbines and therefore have no idea what sort of set-up would be required to generate the required amount of electricity. However, this thought remains at the back of my mind, in case I need to give it more serious consideration in the future.

Kind Regards, John

I was going to make one last year from an old bike wheel that has a dynamo in the middle - just never got round to it.

If I do get round to it this autumn I will do a thread discussing the electronics around safely charging of a lithium type battery and connecting it to the solar lights. It would be nice to have these lights on during the dark winter days -

 

[JohnW2]

Yes, that is what I thought you had intended. .... I rightly or wrongly wondered if you had planned to cover a few places where light not be as intense and for less duration as part of a future plan to realise the best to worst sort of scenario and the ratio betwixt such.

I don't really have all that many options. It's a 3-storey mid-terraced house, hence with windows just front and back, pointing almost exactly West and East Respectively.

Despite the 3-stories, even the top floor rear rooms are fairly obscured by some pretty tall gtrees just beyond the end of the rear garden, leaving front windows as easily the most promising option. However, as you imply, I';ll probably eventually do some experiments with differing locations and orientations.

Kind Regards, John