Lighting an orchid closet - fluorescent or LED? Otherwise?

[fishmommy]

The Jungle Dawn 13w LED bulb I measured today gave 1500 fc at 1 foot distance straight under the bulb.
A foot to either side gave much less, more like 500.
FYI .
I am using it to light a 10inch x 10inch x 20inch tall terrarium for low light plants.

[Ray]

Originally Posted by fishmommy

The Jungle Dawn 13w LED bulb I measured today gave 1500 fc at 1 foot distance straight under the bulb.
A foot to either side gave much less, more like 500.
FYI .
I am using it to light a 10inch x 10inch x 20inch tall terrarium for low light plants.

May I ask about your measuring device?

I tested mine with a Hydrofarm light meter, and saw about 800-900 fc 12 " below and ~400 a foot to the side.

[fishmommy]

Originally Posted by Ray

May I ask about your measuring device?

I tested mine with a Hydrofarm light meter, and saw about 800-900 fc 12 " below and ~400 a foot to the side.

It's just a regular old Hydrofarm light meter. I used a ruler and everything Could my reflector make the difference?
Also, this bulb is not available yet separately. It is 12W (I thought it was the 13 but nope) I bought these for my terrariums, which are 10g tanks stood on end:
Exo Terra Compact Top Nano 8" WITH LED Light Included

[Ray]

Certainly. From what I can see, the Jungle Dawn horizontal light has no lenses on the LEDs, so light can spread pretty widely.

[littlefrog]

The jungle dawns are designed to light up a terrarium (fish tank) style area, which is reasonably narrow but deep. I've been recommending one for a 12x12x18 or similar size. Two for a 24x18x18 tank. All I can say is that nobody goes back to CFLs once they've tried them (unless they need heat, and some people do). People are reporting good color on bromeliads, and great plant growth. A few people say they've sunburned plants with them, I have a bit of doubt on that, but they are bright...

They are rated at 13W, which is a little deceptive. The chips total 13W, but the actual power draw is on the order of 10W using my meter. This is typical for this style of light, something to do with the way the internal ballasts work.

I'm not a lighting engineer or a physicist (my PhD is in molecular biology). So I'm not going to debate photons and lux and the like. All I know is that in real life they work fine. I wouldn't have spent a gazillion dollars converting my growing area to LEDs if it didn't work, believe me. I sell plants for (part of) a living, I'm not going to invest in something just for giggles. I encourage you to try one if you are sceptical, that is the only way to see. If they don't work for you, then you know for sure. I haven't had any complaints. It does bother me somewhat that there are people who insist they don't work because of (... fill in the blank...). They are the same people that said fluorescents didn't work, I think. You won't know unless you try. I'll be happy to take back any of mine that you are unhappy with.

Right now I have a few discontinued white LEDs (12W) that I'm selling at a pretty good discount just to make space. They don't have quite the same color light as the new ones, but it is a good way to play with LEDs for a bit less, they are a high quality light, just an old model. They are $23.99. 'Regular' 13W lights are $36.99 (or 3/$100). There are also 'spotlight' styles available in 24 or 36W, and even some with added red and blue chips to enhance the plant spectrum. If you want UV, I can do that too (but not all those things in one bulb, yet).

I also have some wickedly awesome LED 'striplights' - they look kind of like a t-5 tube but not quite. Same dimensions. I'd say somewhere between a t-8 and a t-5 in real light output. A whole lotta chips in a linear configuration, the whole thing encased in acrylic so it is effectively waterproof. I like to whack them on a table when demonstrating them, try that with a fluorescent! I haven't had time to list them, but if you are interested, drop me a line. I have those in red, white, and blue, very patriotic.

PM me and I'll answer any questions you have (that I can answer).

Rob

[DavidCampen]

It does bother me somewhat that there are people who insist they don't work because of (... fill in the blank...). They are the same people that said fluorescents didn't work, I think.

People say that they don't work? That seems to be a rather silly statement. Who would say that? 100 watts of white LED should work about as well as 100 watts of white linear fluorescent. I have never paid much attention to CFL but I would expect them to be less efficient than linear fluorescent.

I use both LED (a 16 X 10-watt ,red white and blue light bar of my own design) and T5 linear fluorescents as supplemental lighting. I use LED when I want a focusable light source so that I can mount the source a long distance from the plants and I use the linear fluorescent when the lamps can be placed very close to the plants because of the much lower capital cost of linear fluorescent.

[littlefrog]

Always seems there is somebody out there who refuses to change... People still buy 1000W HPS systems. Some people still drive horses to work...

I use a similar strategy. I use fluorescent light over some benches, partly because I didn't have access to the linear LEDs that I have now. Some areas don't work well with the light patterns available with a lot of commercial LED systems (round areas, square areas... I have a long thin area, so use a tube). One downside is that those T5 tubes aren't cheap, and need replacing yearly. In theory the LEDs last a lot longer. So, it is really the same calculation people make when they invest (or don't invest) in energy efficient vehicles for example. Is the upfront premium worth the down-stream benefit? Depends on many factors, and not all of those are cost. So, as an example (retail pricing is approximate, I don't buy retail...).

1 single 4' t-5 strip fluorescent (without reflector) : $30. Add in a reflector for $20 (or build your own, which is what I do, for less). Anyway, about $50.

1 single 4' HO LED light - $100. Need a transformer, unfortunately. Let's say another $50 (can run several strips though). Total, about $150

For the first couple years, the T-5 wins. Need to buy a new bulb every year (yes you do... stretch it to 18 months if you must, but you will be a far happier person if you replace them yearly). Hydrofarm's price for a 4' 54W bulb is $30. Seriously? $30? That is insane. Anyway. After two years you've replaced the bulb once (getting you up to $80). After 5 years you've replaced the bulb 4 times (getting you up to $170). So, payback time is about 4 years? This calculation doesn't take into account energy costs, my HO strips run at about 35W I think, so ~60% of the electricity. If you are cooling your growing area, you have to figure that in too.

Anyway, that should give you some ideas as to the 'payback' times and relative investments. Wait a couple years, and the prices of the LEDs will drop again (they've already gone down substantially, even as the quality has improved dramatically, over the last two or three years).

If you are growing cool orchids like pleurothallids, it might not matter what the LEDs cost, the difference in heat is so substantial it is worth any premium.

Now that I have access to a high quality 'T5 like' LED strip (seriously, these are so much better than most of what is out there, it is ridiculous - there is a lot of junk to be had in LED strips), I will be replacing a lot of my T5s as the bulbs need replacing. The directionality is a problem, I will need to do two LED strips for every one fluorescent strip to get even coverage. A trade-off, as usual. Actually I'll probably do one blue, one red, and one white strip per every 4' of bench.

Originally Posted by DavidCampen

People say that they don't work? That seems to be a rather silly statement. Who would say that? 100 watts of white LED should work about as well as 100 watts of white linear fluorescent. I have never paid much attention to CFL but I would expect them to be less efficient than linear fluorescent.

I use both LED (a 16 X 10-watt ,red white and blue light bar of my own design) and T5 linear fluorescents as supplemental lighting. I use LED when I want a focusable light source so that I can mount the source a long distance from the plants and I use the linear fluorescent when the lamps can be placed very close to the plants because of the much lower capital cost of linear fluorescent.

[littlefrog]

Oh, another advantage of LEDs is they don't shatter into a million pieces when you look at them funny... Or get cold water on a hot tube. Ever had a fluorescent tube shatter on you? Mercury, lord knows what else in them, even if the glass wasn't lethal in itself.

Minor advantage, but when you've had a few near death experiences (use them for 25 years, *&$@ happens...), it can be comforting to know there won't be flying glass coming at your eyes...

[fishmommy]

I also bought one of these to try, since it was so cheap.
Amazon.com: LEDwholesalers 2501WH White 225 LED 13.8 Watt Square Grow Light Panel 110 Volt: Patio, Lawn & Garden
It is giving me 1500 fc at 1 foot and only 80 at 2 ft.

[DavidCampen]

Originally Posted by fishmommy

I also bought one of these to try, since it was so cheap.
Amazon.com: LEDwholesalers 2501WH White 225 LED 13.8 Watt Square Grow Light Panel 110 Volt: Patio, Lawn & Garden
It is giving me 1500 fc at 1 foot and only 80 at 2 ft.

This is why I built my own LED light strip. The commercial ones do not exploit the principal advantage of LED over fluorescent - that it is relatively a point source and thus can be tightly focused. With the commercial LED light strips the light is less focused than even a linear fluorescent and diffuses very rapidly.