ISS greenhouse experiment

[PJay_A]

<p>How large of a greenhouse onboard the ISS would be required in order to help save on ISS operating expenses in terms of providing freshly grown food and oxygen&nbsp;for the crew? Of course, it would also function as a natural CO2 scrubber.&nbsp; I know the Russians had a greenhouse&nbsp;experiment going... Had that experiment provided any edible food, breathable oxygen, or contributed in any way to minimizing ISS CO2 atmospheric content?</p>

 

[bushuser]

<p><font size="3">The Navy experimented in the 1960's with algae oxygen production for submarines.</font></p><font size="2"><p>http://oai.dtic.mil/oai/oai?verb=getRecord&metadataPrefix=html&identifier=AD0420927</p><p>&nbsp;</p><p>In that experiment, 6.2 liters of algae suspension, under very ideal conditions [such as high wattage very-bright lighting] produced 4.5 liters of oxygen per hour.</p><p>&nbsp;</p><p>Humans consume 10-50 cc oxygen/ kg/minute, depending on the level of exercise. So a 50 kg individual needs 500-2500 cc oxygen/minute.&nbsp; That's at least 30 liters per hour.</p><p>&nbsp;</p><p>In this, I have not made any STP corrections, but you see where it is headed.&nbsp; <font size="3">A large facility would be required to provide meaningful amounts of oxygen.&nbsp; But it IS feasable and self-sustaining</font>.&nbsp; Perhaps there's a way to stack thin plates of algae between lamps, like a&nbsp; car battery, to reduce the space occupied by the device.</p></font>

 

[kelvinzero]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>The Navy experimented in the 1960's with algae oxygen production for submarines.http://oai.dtic.mil/oai/oai?verb=getRecord&metadataPrefix=html&identifier=AD0420927In that experiment, 6.2 liters of algae suspension, under very ideal conditions [such as high wattage very-bright lighting] produced 4.5 liters of oxygen per hour.&nbsp;Humans consume 10-50 cc oxygen/ kg/minute, depending on the level of exercise. So a 50 kg individual needs 500-2500 cc oxygen/minute.&nbsp; That's at least 30 liters per hour.&nbsp;In this, I have not made any STP corrections, but you see where it is headed.&nbsp; A large facility would be required to provide meaningful amounts of oxygen.&nbsp; But it IS feasable and self-sustaining.&nbsp; Perhaps there's a way to stack thin plates of algae between lamps, like a&nbsp; car battery, to reduce the space occupied by the device. <br />Posted by bushuser</DIV></p><p>Im missing something. Oh, wait. I got it as I was writing. A litre of oxygen means of gas, not compressed and not weighing around a kg!</p><p>Im still missing something though. Why are we not&nbsp;using it? It might be more practical to just ship up water right now and break it into oxygen but to me that is like saying it would have been more practical to send plastic people to the moon since that would also simplify lifesupport. What more important technology could we be developing on the ISS than an indefinite lifesupport system?<br /></p>

 

[dogfish6sp]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Im missing something. Oh, wait. I got it as I was writing. A litre of oxygen means of gas, not compressed and not weighing around a kg!Im still missing something though. Why are we not&nbsp;using it? It might be more practical to just ship up water right now and break it into oxygen but to me that is like saying it would have been more practical to send plastic people to the moon since that would also simplify lifesupport. What more important technology could we be developing on the ISS than an indefinite lifesupport system? <br /> Posted by kelvinzero</DIV></p><p>&nbsp;</p>A big part of the problem is getting enough energy to power the intense light bulbs, and then to deal with the heat created by the lighting. <br /><br />&nbsp;It would be pretty cool if we could just use the light from the sun, but there are some large problems with that as well.&nbsp; Obviously in Low Earth Orbit you have the issue of having such quick "days" of sunlight.&nbsp; Another huge issue is making some sort of large window for all the light to pass through while still holding up to the vacuum of space. &nbsp;<br /><br />&nbsp;One more question I'd like to learn about, is how plants might deal with getting such a larger spectrum of light.

 

[kelvinzero]

<p>Rather than windows I was imagining panels rather like solar power panels or radiators. Algae would circulate though transparent pipes that screen unwanted wavelengths. Radiation might not be a problem if the algae breeds fast enough. This isnt an informed opinion but I like the obvious biological analogy.</p>

 

[CalliArcale]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Rather than windows I was imagining panels rather like solar power panels or radiators. Algae would circulate though transparent pipes that screen unwanted wavelengths. Radiation might not be a problem if the algae breeds fast enough. This isnt an informed opinion but I like the obvious biological analogy. <br /> Posted by kelvinzero</DIV></p><p>If you wanted to, you could "pipe" sunlight into the vehicle not through windows but through fiber optics.&nbsp; Not sure how much you'd need to be effective; it might still be simpler to convert solar energy into electricity to run a bank of flourescent light bulbs. </p> <div class="Discussion_UserSignature"> <p> </p><p><font color="#666699"><em>"People assume that time is a strict progression of cause to effect, but actually from a non-linear, non-subjective viewpoint it's more like a big ball of wibbly wobbly . . . timey wimey . . . stuff."</em>  -- The Tenth Doctor, "Blink"</font></p> </div>

 

[a_lost_packet_]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>If you wanted to, you could "pipe" sunlight into the vehicle not through windows but through fiber optics.&nbsp; Not sure how much you'd need to be effective; it might still be simpler to convert solar energy into electricity to run a bank of flourescent light bulbs. Posted by CalliArcale</DIV></p><p>Some LEDs Grow Lights have shown promise.&nbsp; Fine tuning them for the cultivation of bio-generated resources for space habitation would be right up NASA's alley.</p><p>But, cracking water seems to be very effective.&nbsp; I think any plans for generating atmosphere for a space habitat must always first consider the availability of water.&nbsp; If it's available, then it can be used and, more importantly, recycled.</p><p>The Elektron, oxygen generator.&nbsp; </p> <div class="Discussion_UserSignature"> <font size="1">I put on my robe and wizard hat...</font> </div>

 

[CalliArcale]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Some LEDs Grow Lights have shown promise.&nbsp; Fine tuning them for the cultivation of bio-generated resources for space habitation would be right up NASA's alley.But, cracking water seems to be very effective.&nbsp; I think any plans for generating atmosphere for a space habitat must always first consider the availability of water.&nbsp; If it's available, then it can be used and, more importantly, recycled.The Elektron, oxygen generator.&nbsp; <br /> Posted by a_lost_packet_</DIV></p><p>Yeah, it's pretty darned efficient.&nbsp; The only problem is that it consumes water, so it's not self-sustaining.</p> <div class="Discussion_UserSignature"> <p> </p><p><font color="#666699"><em>"People assume that time is a strict progression of cause to effect, but actually from a non-linear, non-subjective viewpoint it's more like a big ball of wibbly wobbly . . . timey wimey . . . stuff."</em>  -- The Tenth Doctor, "Blink"</font></p> </div>