paste on vents for flasking

[naoki]

I got LED strips light off Ebay cheaply. Getting the power supplies from the same source...

The LED strips typically have a beam angle of 120o (60o from the vertical) which means that at 1 foot away, the beam covers an area 3.5 ft. I guess your shelves are only 2 ft wide, so you can have the flasks about 18 cm from the LED strip. This means more flasks in less space!

I am not sure how many strips to mount to achieve a desired lux. You would need to experiment.

Tyrone, which LED strips did you get? I've been looking around since you mentioned 5630 in the DIY LED thread, but all of them have pretty low efficiency. They don't seem to be worth getting. The mid-power LED chip like Samsung LM561B can have decent efficiency (when driven really soft), but once they are made into LED strips, they all seem to be pretty low efficiency. And lots of strips don't specify which chips they are using (they are probably Chinese Epistar 5730 copy??). They don't provide enough data, but 5630 strip seems to be in the range of 50-110 lumen/watt.

I'm guessing that part of the problem is that they are designed for flexibility in expansion, and uses constant voltage drivers of standard voltage (like 12 or 24V). In other words, you can cut the strip to the custom size (to fit into a kitchen shelf etc), and the same driver can be used. To achieve this flexibility of LED strips, they have to add resistors to adjust the voltage per module (which waste energy). Then these modules were connected in parallel. With this design, I'm not sure how you can use lower current to achieve efficiency.

So it seems that it is much better to use something like Philips XF-3535L (around 140-150 lumen/watt), which is usually driven by constant current driver, and you can have at least 50% or more light per used energy than 5630 LED strip. With our grow area, we can pretty much know how much light we need from the beginning (and flexibility isn't so important), so it seems to be better to get the required amount of LED, and use the correct driver, which provide the optimal efficiency/light output balance in my opinion.

 

[TyroneGenade]

The major gain in efficiency is in ditching the ballast needed for the T8 lamps. It produces LOADs of heat.

I agree, with the strips, they produce the same amount of light per W as a T8 lamp but there isn't a ballast eating another 20-30% of power ontop of the power used by the lamp itself.

For Gary, the major benefit is that he could replace Eskom (a notorious energy provider in South Africa) with some solar panels instead...

I used Natural white LED strips as I was concerned with aesthetics as much as photosynthesis. Warm white is probably better for plant growing.

I doubt much more than 30 or 40 PPFD is needed to keep orchids happy. They are, after all, shade plants. Some where on the forum someone showed a pic of a Paph in the wild with a lux measurement and it was really low...

I don't think we need very efficient, high PPFD, lamps to keep Paphs happy.

My single strip of 5630 natural white grows Egeria densa without issues and it is a "high light" plant.

 

[naoki]

Well, plants are phenotypically plastic (since they can't move easily), and they can grow in low light slowly. But the growth (of adult paphs) is likely to be really slow with 150-200fc of peak intensity (approx. from the PPFD values you mentioned). But if that is the place where the plant germinate, it is stuck with the weak light for its life (and they should be "happy" about not being dead, I guess oke. We use dim light for the flask, but that's because photosynthesis usually isn't the only source of carbon in flask.

I would rather save money by using high efficiency and spend the money to buy more plants (or wine). But I guess that not everyone cares about paying hundreds of extra dollars for electricity every year. With solar, this may not be a big issue, but solar power isn't free, neither. As you mentioned, 5630 can be used for high light plants, but incandescent light bulbs can be used for them, too! Density of light and efficiency of light is completely different things (I know that you obviously know this, but I thought that other people may misunderstand your post). It is a bit off topic, but I was surprised by the amount of PAR from 65W bulb when I measured it:

light               PPFD@1'          footcandle  watt  PAR efficiency
GE 65W Miser Flood  70 micromol/m^2/s   324fc   64.5W  1.1 micromol/J
CFL 16W Flood       19 micromol/m^2/s   122fc   17.2W  1.1 micromol/J
CFL 19W Flood       24 micromol/m^2/s   149fc   18.5W  1.3 micromol/J

Models for the CFL: Commercial Electric EDXR-30-16 (16W, sold as 65W equivalent), EDXF-40-19 (19W, sold as 85W equivalent).

 

[TyroneGenade]

Good points, Naoki.

If PAR/W efficiency is the name of the game then nothing beats Ultra Grow Wave T5HO at 1.61 PAR/W.

For LEDs at 1000 mA, the best bets are LED CREE-xml Neutral White
and warm whites (4.43 and 3.63 respectively). The latter has a lot more 650--700 nm red than the other. It is easy (with practice) soldering these into an array but they are not cheap.

Now I will change the subject.

I got some cheap spot bandaids at Dollar General and gave them a test run in the autoclave. To my surprise the plastic spots melted onto the metal babyfood bottle lids! I worried the glue might melt and then the spots would detach. I now worry about the perforations over the cotton wadding... Oh well, time for another experiment.

 

[Migrant13]

This flasking and LED lighting discussion is out of my league. However, I love this thread and all the interesting discussions. Good thing I don't live near Trithor or Eliseo otherwise my house would be a lot greener than it already is and my wallet would a lot thinner!

 

[Alex]

Gary, I can't see that you will have any choice but to sell some (a lot!) of plants, unless you have space on a commercial scale. This might assuage your wife's financial concerns, too!

If (when) you start the sales/nursery, will you be able to export to Europe easily?

 

[Trithor]

Exporting from South Africa should pose no problems

 

[Alex]

Excellent! I look forward to your first list.

 

[fibre]

Exporting from South Africa should pose no problems

Are you sure? Do you get CITES for your Paphs?

 

[Trithor]

I need to investigate next week, but I believe it to be possible

 

[gonewild]

It's not hard to get CITES permits for artificially propagated plants, it just costs money and time.

 

[Bjorn]

To my knowledge, flasks are exempt the CITES regulations and therefore Phyto certificate should suffice. There might be local regulations though.

And Gary, pls. put me on the list as well, although I have no more room for plants. You know, we insane folks do not pay attention to obvious things like lack of space etc. Envy you your climate, makes it much easier to follow you crazy ambitions. Personally I think that it is much better to have a bunch of plants of each species, just in case, and ten of a kind look much better than just one..

btw. believe it or not, I make wine here, from grapes

 

[Trithor]

btw. believe it or not, I make wine here, from grapes

Now there is a new hobby for me to try!