low-cost solar garden lights

[Dave_H]

I just thought to start a discussion about solar garden lighting, what's new, good, or not-so-good.

For sure there is a lot of low-priced junk out there, which does not hold up long, maybe not even one year. OTOH there are some reasonable good ones out there at decent prices e.g. $10 or less.

To be sure, most of these produce only small amounts of light, good for a bit of local illumination, as "markers". None are not going to save enough energy to pay for themselves. I estimated one small lamp taking 75-100 years to break even, at current line costs! But they are convenient, moderately useful, and fun to test out, and just to look at.

Usual disclaimed, this is not product endorsement, just opinion and personal experience.

I just picked up an amazing metal/glass filament LED lantern from Home Depot for around $5 (reduced price). These are bulk packaged i.e. stuck into a cardboard base, almost no instructions or specs. It runs on 1AA NiMH; solar panel is about 4 sq. in. of crystaline silicon (mono- I think). The light is quite bright (14 lumens) and with a good days' sunlight this time of year (at 45 degree latitude and non-optimal aiming) will last at least 3-4 hours, then drops to dim for a while longer.

I may try to get a night shot, regrettably my phone camera does not do justice to it.

Dave

 

[TPA]

I've not played with solar outdoor lighting in years, but it traditionally was a lot of promises with very little performance. I know it's change A LOT since then.

One of my neighbors has a bunch of them in a single planter. After the hurricane they'd bring them inside to light up the condo then set them outside the next day. They used to have them along their pathway, but never put them back out, so now she has a "light plant" going.

 

[Dave_H]

On the left is flickering solar light from Dollar Tree for $1.50. Unlike another of
similar appearance, it uses a single self-flickering 5mm amber LED. Cell is 150mA NiCd
which sounds low, but light holds up well over the night. Effect is not totally realistic,
but overall good for the price!

On the right is an amazing little RGB colour-changing light from Giant Tiger ($1 each
in pack of 10). This one held up outside over the winter, also has been dunked a few times
in water and dried out, still OK. It uses a 40mAh NiMH button cell, which sounds low, but
holds up overnight with a good dose of sunshine.

Dave

 

[Dave_H]

There are some downsides to keep in mind for solar garden lighting.

You will never recover the cost of product in power savings. A ballpark estimate I did on $1.40 (at the time) small DT solar spot yielded 75-100 years based on current ac power rates; many times the life of even the best solar lights, which this was not. That does not include energy required to manufacture the product which would be very hard to estimate.

Also, some still use NiCd cell which may be non-replaceable, or with sufficient difficulty to discourage most people. Only product being properly e-recycled would stop Cadmium from reaching landfill. Cadmium is toxic and one of six materials (four heavy metals and two brominated flame retardants) covered by "RoHS" regulations.

I just found another DT mini spot which is impressive, but contains 500mAh NiCd cell, and was very difficult to open; sustained some minor damage (but still works).

Dave

 

[Dave_H]

Below is the little DT solar spot. It does not provide a lot of light, but fine to light an otherwise dark small area. It can run all night with a good dose of sun during the day. Solidly built, not bad for $1.50.

I usually cannot find these items online under DT Canada or US sites, but sometimes a UTube video for some.

Dave

 

[WarriorOfLight]

In the last ~5-10 years I had a lot different Solar Lights mostly for Garden decoration.

Most of the Lights do not last even a year and the water resistance is mostly below average. There is not a rule that more expensive Lights are better or cheap ones more trash... In my opinion most of this lights are not worth the Money, no matter of it is $5 or $20...

-- edit auto corrected typos --

 

[Dave_H]

Disappointing for sure that lights don't hold up for a year, however, I am interested in details of what is failing. When a light fails I'll make a reasonable effort to revive it, otherwise keep it for spare parts, or dispose as e-waste. Cells are removed and recycled (especially NiCd).

Common failures include corrosion of switches (where present) and battery contacts, sometimes the cells themselves corrode at the ends.

Dead cells can develop, due to low quality, also likely due to overcharging/discharging in some designs which allow it.

Solar panels deteriorate over time. It happens on crystaline panels, apparently worse in regions of higher solar intensity (esp. UV) such as southern U.S. Here it is moderate and may take several years, by which time something else may have failed. Amorphous panels can visibly deteriorate, occasionally I find ones which fail (no output) but otherwise appear good.

Dave

 

[WarriorOfLight]

Disappointing for sure that lights don't hold up for a year, however, I am interested in details of what is failing.

Mostly water was the problem and everything was corroded. That is than the dead of the device. I only had one or two times a dead NiMH cell.
What I observed is that most of that solar lights are not sealed with O-Rings in any way. Heavy rain will than find easy a way into the light.

 

[vincent3685]

Picked these up on sale, at Costco, about a year ago. They put out 30 lumens and each comes with a 14500 LifePo battery. The housing and arm are made of metal and seem pretty robust. if they're fully charged they will usually last all night and are surprisingly bright. About the best I've seen out there so far;

https://www.costco.com/tommy-bahama-solar-led-pathway-lights%2c-30-lumen%2c-6-pack.product.4000227495.html

And no, I don't live in NY. Just using a VPN.