@paul Supposedly it only works around a peak of 300nm with no effect within 50nm above and below. If you can find cheap leds in that spectrum you will be a millionaire in the waste water treatment industry they need just under 300nm for uv sterilizers, which is the major power consumer on treatment plants. Standard is florescent.<div>
<br></div><div>@Mate I agree some plants absorb some light more than others, but in general you need blue and red. There are two basic<span style> chlorophyll types, A and B, and each has a red and blue adsorption peak. A is around 430 (blue/violet) and 660 (deep red) while B is around 460 (blue) and 630 (red).</span><span style> </span><a href="http://www.biologie.uni-hamburg.de/b-online/e24/3.htm">http://www.biologie.uni-hamburg.de/b-online/e24/3.htm</a> Green/yellow is mostly useless. The thing with leds is they produce a very tight band of wavelength and plants only respond to a tight band of red/blue so you can buy led lighting and get screwed. Marine fish tanks get algae blooms with 660nm so I think that would be a good place to start with tests on algae. Plant growers seem to be using 630nm. But 630's are brighter than 660's of the same power output so it could just be a power issue.</div>
<div><br></div><div>Here's some info i got on fish tank forum. (They seem to be the only guys trying to grow algae (marine) with leds, outside of academia behind pay walls.</div><div><br></div><div><span style>"One other interesting result that someone posted was that they were running a scrubber with an array of 6 3W 660 reds for about 6 months, and when they added one 455 blue LED to the mix, the growth changed dramatically, not so much in bulk but in form; the algae 'roots' where it was attached to the screen/substrate became substantially stronger (harder to scrape the algae off) and the algae strands thenselves became thicker. This suggests that the blue component does not so much contribute to overall growth as it does to some other strengthening factor."</span></div>
<div><span style><br></span></div><div><span style>Supposedly a and b are for absorbing light at different times of day.... I dunno, but I do agree that the field is ripe for hackerspace exploitation. </span></div><div><br>
<div class="gmail_quote">On Thu, Sep 6, 2012 at 12:15 PM, Paul Szymkowiak <span dir="ltr"><<a href="mailto:paulszym+cchs@gmail.com" target="_blank">paulszym+cchs@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
also in SMT flavours, but
apparently not as bright:<div><br></div><div> <a href="http://www.ebay.com.au/itm/290741652723" target="_blank">http://www.ebay.com.au/itm/290741652723</a></div><div> <a href="http://www.ebay.com.au/itm/251024873978" target="_blank">http://www.ebay.com.au/itm/251024873978</a></div>
<div> <a href="http://www.ebay.com.au/itm/261092332506" target="_blank">http://www.ebay.com.au/itm/261092332506</a></div><div class="HOEnZb"><div class="h5"><div><br><br><div class="gmail_quote">On 6 September 2012 08:04, Paul Szymkowiak <span dir="ltr"><<a href="mailto:paulszym+cchs@gmail.com" target="_blank">paulszym+cchs@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div>>
<span style="color:rgb(34,34,34);font-size:13.333333969116211px;font-family:arial,sans-serif">Also you need UV for vitamin d production which cannot be produced by leds...for now. </span> <div>
<br></div></div><div>Would these not be suitable?</div><div><br></div><div> <a href="http://www.ebay.com.au/itm/200609595424" target="_blank">http://www.ebay.com.au/itm/200609595424</a></div><div> <a href="http://www.ebay.com.au/itm/271023896302" target="_blank">http://www.ebay.com.au/itm/271023896302</a></div>
<div><br></div><div><br clear="all">Paul<span><font color="#888888"><br> <br>Paul Szymkowiak <br><div><a href="http://gplus.to/paulzee" target="_blank">gplus.to/paulzee</a></div><div><a href="http://twitter.com/paulzee" target="_blank">twitter.com/paulzee</a></div>
<div><a href="http://twitter.com/smartenergywins" target="_blank"></a><a href="http://twitter.com/hackmelbourne" target="_blank">twitter.com/hackmelbourne</a></div></font></span><div><div><div><br></div>
<br><br><div class="gmail_quote">On 5 September 2012 09:07, cole santos <span dir="ltr"><<a href="mailto:cksantos85@gmail.com" target="_blank">cksantos85@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div class="gmail_quote">Why use a rotating array? Your plants will quickly outgrow such a small area. Make sure to use at least 3w leds or you wont get enough canopy penetration. Also you need UV for vitamin d production which cannot be produced by leds...for now. Check out plasma lighting, more efficient that LED. For hydroponics I am working on integrating organic nutrient sources such as fish effluent, biogas effluent, and human waste products. For space applications we need aeroponics to reduce total required water volume. To do aeroponics with organic nutrient sources you need an atomizer that doesn't clog. Looking into centrifugal atomizers atm. But in reality food production is a luxury when you can eat chlorella exclusively. Chlorella is easy to grow and is the most efficient method of co2 removal and o2 production by volume of area required. Hence my algae reactor project.</div>
<div><div>
<div class="gmail_quote"><br></div><div class="gmail_quote">On Wed, Sep 5, 2012 at 11:30 AM, Matt Joyce <span dir="ltr"><<a href="mailto:matt@nycresistor.com" target="_blank">matt@nycresistor.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
Some folks at NYC Resistor were working on a growing apparatus using a<br>
rotating array of leds operating at different wavelengths.<br>
<br>
pic of it... behind and to the left ( looking at me ) of my glorious visage.<br>
<br>
<a href="http://www.flickr.com/photos/openfly/7558683614/" target="_blank">http://www.flickr.com/photos/openfly/7558683614/</a><br>
<br>
I'd love to see something like a git project setup for space based<br>
growing testing kits.<br>
<br>
Throw in some STL / code / eagle etc for some citizen science style<br>
testing.... aka repeatable experimentation. And we have some real<br>
live testing of procedures for open source scientific research into<br>
how to grow stuff in hazardous areas safely.<br>
<br>
I think that would be a great easy enough project to get into. And it<br>
would probably iron out some of the kinks in getting a bunch of people<br>
to be able to contribute to a much larger goal.<br>
<span><font color="#888888"><br>
-Matt<br>
</font></span><div><div><br>
<br>
On Tue, Sep 4, 2012 at 2:25 PM, cole santos <<a href="mailto:cksantos85@gmail.com" target="_blank">cksantos85@gmail.com</a>> wrote:<br>
> I have nothing running ATM but I did a lot of monoculture algae work when I<br>
> was in aquaculture program at UH<br>
><br>
> <a href="http://contrails.iit.edu/DigitalCollection/1962/AMRLTDR62-116article03.pdf" target="_blank">http://contrails.iit.edu/DigitalCollection/1962/AMRLTDR62-116article03.pdf</a><br>
><br>
> This is where I got my ideas.<br>
><br>
> My test reactor is going to be 18" x 24" x .2"<br>
><br>
> Man sized reactor will be 24" x 48" x .2-.09 with ~20 of them in parallel.<br>
><br>
> Algae will be extracted via this device.<br>
><br>
> <a href="http://www.parc.com/services/focus-area/clean-water/" target="_blank">http://www.parc.com/services/focus-area/clean-water/</a><br>
><br>
> and o2 / co2 / vox will be monitored by sensors on arduino control.<br>
><br>
> Short term plan is to replicate the boeing experiment and adapt for longer<br>
> term production<br>
><br>
> Longer term, utilizing human wastewater as a nutrient supply and electricity<br>
> source with waterwater fuel cells.<br>
><br>
> Each project is part of a larger plan for a compact biological closed cycle<br>
> habitat.<br>
><br>
><br>
><br>
><br>
><br>
> On Wed, Sep 5, 2012 at 11:10 AM, Máté Ravasz <<a href="mailto:ravaszmeister@gmail.com" target="_blank">ravaszmeister@gmail.com</a>><br>
> wrote:<br>
>><br>
>> Hi,<br>
>><br>
>> I've just started to build up my own algae cultures at home last month.<br>
>> Seeing your post on how far you've progressed already in this, I immediately<br>
>> became jealous. Would you by any chance have any publicly available data on<br>
>> how your setup runs? I am building a sunlight powered reactor at the moment,<br>
>> but I would be eager to read up on more advanced methods if possible.<br>
>><br>
>> Thanks for any info,<br>
>> Mat<br>
>><br>
>><br>
>> On 4 September 2012 22:48, cole santos <<a href="mailto:cksantos85@gmail.com" target="_blank">cksantos85@gmail.com</a>> wrote:<br>
>>><br>
>>> For big area lighting plasma is more efficient than leds.<br>
>>> <a href="http://www.plasma-i.com/index.html" target="_blank">http://www.plasma-i.com/index.html</a><br>
>>><br>
>>><br>
>>> On Wed, Sep 5, 2012 at 10:46 AM, cole santos <<a href="mailto:cksantos85@gmail.com" target="_blank">cksantos85@gmail.com</a>><br>
>>> wrote:<br>
>>>><br>
>>>> LED's are more expensive than florescents...and that is after order of<br>
>>>> magnitude reductions in cost over the last few years. I found some vendors<br>
>>>> in china for LED lights. Florescent technology requires bulb changes every 6<br>
>>>> months to a year, this makes it unworkable for space, but good for earth<br>
>>>> testing. LED research on optimal spectrum for algae growth is an open<br>
>>>> research field. Another problem is the design for my algae reactors needs<br>
>>>> lights that are 360, but leds are about 130 deg. a bi directional light<br>
>>>> would cost a lot more due to custom nature of such a light, another option<br>
>>>> is to just stack 2 lights back to back... but now you've doubled you costs<br>
>>>> and lighting is more that 50% of the total cost.<br>
>>>><br>
>>>> On Wed, Sep 5, 2012 at 10:25 AM, Jerry Isdale <<a href="mailto:isdale@gmail.com" target="_blank">isdale@gmail.com</a>> wrote:<br>
>>>>><br>
>>>>> Growing in space requires light. Space stations may be able to orient<br>
>>>>> themselves for full time growing but Colonies on moons, etc will need some<br>
>>>>> power source for when their rotation takes them into night (moon night = 2<br>
>>>>> weeks).<br>
>>>>><br>
>>>>> This article talks about using LEDs powered from a small nuclear power<br>
>>>>> source, similar to that powering the Curiosity Rover.<br>
>>>>><br>
>>>>><br>
>>>>> <a href="http://www.forbes.com/sites/brucedorminey/2012/08/31/space-farmers-leds-as-key-to-nasas-permanent-lunar-life-support/" target="_blank">http://www.forbes.com/sites/brucedorminey/2012/08/31/space-farmers-leds-as-key-to-nasas-permanent-lunar-life-support/</a><br>
>>>>><br>
>>>>> Jerry Isdale<br>
>>>>> <a href="mailto:isdale@gmail.com" target="_blank">isdale@gmail.com</a><br>
>>>>><br></div></div></blockquote></div></div></div></blockquote></div></div></div></div>
</blockquote></div><br></div>
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