Outdoor Dusk to Dawn Solar LED Flood Light?

[WebHobbit]

Can anyone recommend a decent solar LED floodlight setup for my backyard? This is a LARGE rural property so I'd like some WIDE coverage with a good 500+ lumen output. All I am finding are crappy low output/shower-head junk.

[kaichu dento]

I've been buying the Probrite 8500 lumen fixtures for a couple of years now and like them for not only their brightness, but also pleasant color and non-glare appearance. They've actually got three sizes, ranging from $55-120 at Home Depot, but I've also found good prices on eBay for them too.

[WebHobbit]

Hmmm...which models are solar powered? All I see are direct wire. Or did you roll your own?

[kaichu dento]

For actual solar powered lights I've yet to see anything really good yet.

[bigburly912]

Not to be discouraging but there aren’t any good ones sadly. The batteries last no time and half the time they don’t charge well enough to put out any light. I’ve tried everything from 20 dollar harbor freight to as much as you want to spend and nothing has lasted any amount of time or worked well enough to justify. If you find a good one you let me know. If it’s still good after 6 months I’ll buy one. It’s really been bad.

[Dave_H]

Sorry I can't recommend anything specific, but to the OP: approximately how much area (sq ft.) do you need
to cover, and how much sunlight would your location get? That might help filter out the smaller stuff,
from what you need. And I guess, how much do you want to spend (or will you figure that out when to
see what you want)?

Would this be "always on" or would motion-detector work? Also there are products which are always
on at lower intensity but go brighter on motion detection.

Here is example of one found in search (disclaimer, I am not endorsing this company or products).

https://www.deelat.ca/solar-lighting...SABEgJ5y_D_BwE

When you find something suitable perhaps some of us could help scrutinize the specs/claims, as a "sanity" check.

As for "shower-head" yes those products are still out there, some using 5mm "indicator LEDs" as they are called...better designs use proper SMT LEDs or COB.

Dave

[Dave_H]

I've checked out a couple of larger local stores and generally not impressed with solar outdoor lighting
of this type. In many cases the specs are incomplete, even the battery capacity is not always stated.

Example product has good specs but they need to be interpreted. It can output 2000 lumens, 20W
at maximum which on the surface seems good. Battery capacity is only 38.5Wh so at most you
would get less than 2 hours of operation at that level. That assumes 100% battery capacity available which
will not be the case; guess 75-90% if it's a good design. Light does has several lower settings down to 150
lumens, but is that high enough; it's what you can get from a small flashlight.

Solar panel rated 5W is likely/usually peak, which is at noon with sun overhead on a sunny day. So don't expect
battery to fully charge in 8 hours. For fixed panel, available current will vary during light hours. You would
need to budget for cloudy days or partial cloudiness as well as seasonal changes.

A more realistic estimate based on 100 lumens/W, 400 lumens at 80% efficient (5W), you would
get perhaps 6 hours or so per night. For consistent operation the battery would need to be charged
every day, but not from a 5W panel (10-15W likely). Fully discharging the battery every day would
not help its lifetime, so higher capacity is indicated (if possible). A light like this needs to be "over-engineered",
the degree depending on user's needs.


Dave

[JustAnOldFashionedLEDGuy]

500 lumens does not sound very bright for a large property. If you want dusk/dawn always on, you are looking at a big system, with a big panel, and a big battery. You are better off just trenching a 24V wire and get a reasonable sized light.

[Dave_H]

500 lumens does not sound very bright for a large property. If you want dusk/dawn always on, you are looking at a big system, with a big panel, and a big battery. You are better off just trenching a 24V wire and get a reasonable sized light.

Good point, 500 lumens is not much more than a 40W incandescent puts out. LEDs can do much
better power-efficiency wise of course.

If running low-voltage power cable is accepted, I can't help but think that some of this 12/24vdc
automotive LED "auxiliary" lighting product might provide a solution. It is meant for trucks, farm
equipment, and offroad vehicles but also for fixed use. Most that I've seen are rugged and very
well sealed, and runs from 10-30vdc at constant power/brightness (or nearly so) at very high efficiency.

One issue is that "spot" style lights tend to have narrow beams, but others such as some "light-bars"
may be more like directional floods, possibly having broad enough coverage.

The whole arrangement could be switched from one location either by a timer, photoelectric or even
manual switch.

If power-fail operation is required, arrangement with local battery with charging over power cable is
possible but of course adds cost; and batteries require proper care and be maintained.

Just throwing out a bunch of ideas.


Dave