May 5, 2014
Interesting idea ! You may want to do some more research into how they store CO2 (if at all), and what happens at night, when they don't photosynthesize. For example, trees store CO2 as long as they're alive, and they release it when they die and decay. And then additional research and development would be required to actually turn this into a building product, that may be usable in at least some parts of the world. Cheers !..
May 9, 2014
Hi Michael, Thanks for this novel and innovative proposal. Are you aware of any research or proofs of concept? I ask because like Doron I foresee that the biggest challenge will be demonstrating (a) CO2 sequestration, and (b) that sufficient cyanobacterial light can be generated to replace mechanical light. If the data and proof of concept is not yet available, then a good thought experiment would be to consider what evidence you need to accumulate to demonstrate your concept and how you might go about producing it. Looking forward to your next round of edits, -Shane
May 9, 2014
An interesting paper on a cyanabacterial CO2 sequestration mechanism freely available for PLoSone: http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0071581
May 12, 2014
Thanks for the proposal! Its sounds very interesting! Could you just give us more information regarding the actions needed and other questions in blank? Looking forward to the new developments of your proposal! Best, Sara
May 12, 2014
More updates will definitely be added soon (as soon as I have some more time to research it more thoroughly). Interestingly, at night cyanobacteria fix nitrogen and can release hydrogen. This actually makes them a very good source for fertiliser when the biomass outgrows the available medium. There is the possibility the the provision of light may a little unrealistic as they produce very little light (which is why I have looked into dinoflagellates for supplying flashes of light which could be useful in advertising and art). I think that realistically they are far better at carbon sequestration (about 7 liters of culture sequesters the same amount of carbon as one tree [I have to redo the calculations though before I add it to the proposal]). This is an extraordinarily large amount of carbon dioxide that can be sequestered. Another advantage is that these bacteria can be engineered or optimised to produce other products.
May 18, 2014
Dear mcrone, I like your proposal. You could provide more details on the impact of the "cyanobacteria plants", where they would be built, the size and capacity etc. Are you planning on having on-site plants such as solar panels or a grid to supply power to multi units? Also, you can explain a little bit more about how the energy would be transformed into electricity for instance. Is it possible? How would you maintain this system? Are the maintenance cost high/low? what would it require? I wish you the best of luck! Gunesh
Jun 17, 2014
I want to encourage you to keep promoting this concept. Just as bacteria are incredibly prolific and important in ways we are just beginning to understand your research and the support of similar projects could become THE viable solution to resource depletion, emissions sequestration and photosynthetic fuel sources. I agree with Gunesh and others that more details are needed, but the proposal is excellent.
Maryette Haggerty Perrault
Jun 20, 2014
mcrone thanks for submitting this well organized and thoughtful proposal. I'm curious if you could elaborate on what differentiates this particular project from other existing photosynthetic bioreactors (photobioreactors)? Is it simply cyanobacteria's the ability to fix nitrogen at night and sequester carbon during the day in addition to creating biofuel or is it more than that? Would this be a closed system to prevent engineered cyanobacteria from escaping into the natural environment? Thanks again!
Jun 20, 2014
Traditional bioreactors are designed for other functions, not primarily to fix carbon. This system is primarily designed to fix carbon, with the added benefit that bacteria can be engineered for other functions (like biofuel and pharmaceutical production). The idea is to make this as closed as possible so that it remains sterile (to prevent the overgrowth of other bacterial species). This would actually be ensured through a few mechanisms. (1) is the design of the actual incubator, the polyurethane bag allows for a sterile culture once and then it can be discarded, the incubator in an urban setting is more complicated, but could be adequately sealed and (2) the alkalinity of the medium ensures that pretty much only the cyanobacteria can grow (some people actually grow spirulina at home as a source of food and this alkalinity ensures the safety of that) and (3) the specific medium required would limit the growth outside of the bioreactor environment.
Saravanan Dhalavoi Pandian
Jun 23, 2014
Hi, Thank you for your interesting concept!! It would be great to add more clarity on 1. How this concept would reduce the building sector emissions which is arising from energy consumption of the building, embodied energy in building and emissions of non-CO2 GHG gases. 2. As you know, Carbon Sequestration (permanent) is a technological challenge and CO2 recovery from small multiple reactors in urban setting would be more complicated 3. The same challenge in point 2 is applicable to recovering Hydrogen from the multiple reactors and using them to produce energy which can be used in buildings (possibly fuel cells?) All the best, Saravanan.
Jun 23, 2014
Thank you for your feedback saravanan. In response to your questions: (1) The function is relatively limited to mitigation of CO2 emissions. It decreases the net emissions of CO2 rather than directly affecting CO2 emissions. Reactors could in future be incorporated into the outside walls of buildings, allowing for an insulating effect of the medium. (2) The carbon will be sequestered in the form of biomass in this example. This would be no more complicated that cleaning leaves off of a sidewalk in the long run and in fact would probably be simpler. This technique is essentially similar to Iron fertilisation of marine water (encouraging phytoplankton to grow and sequester carbon) which is recognised as a way to remove carbon from the atmosphere for a period of time, although the long term effects are not known at this point. [http://www-formal.stanford.edu/pub/jmc/progress/iron/iron.html] (3) I agree that logistically the hydrogen part does not make sense at this point. That is used merely as an example of how bacteria can be engineered for additional functions. Small multiple reactors are suggested to replace trees in urban settings. It is far easier to house a bioreactor than 360 trees. This individual effort may have little effect compared to large forests, however, if it is implemented on a large scale it could be more beneficial (and additional products can be produced). The greater the adoption the more logistical sense it would make to collect the products produced by the bioreactors.
Laur Hesse Fisher
Jul 29, 2014
This proposal has been moved from the "Building efficiency" to the "Land Use" contest by the Climate CoLab Fellows.
Aug 6, 2014
Novelty: 3/5 Small-scale cultivation of cyanobacteria in bioreactors is not particularly novel. Workability: 3/5 Relatively easy to create a prototype, but scalability of the technology is much more challenging. Effectiveness: 2/5 Climate impacts will depend on life-cycle of the biomass produced, which is not considered in detail in the proposal. Additional focus on the usage of the biomass (for biofuel or fertilizer) would strengthen the proposal. Emphasis on the biomass production is understandable, but the proposal needs a description of the context and rationale for the production technology. Overall net benefits may be questionable, considering embodied energy, nutrient provision, biomass drying, pH adjustment, etc. Thoroughness: 3/5 Not very clear what is proposed to do and when. What specific actions will be taken, who will take them, and when? The various component costs should be summed and a total proposed cost should be indicated. The time line should be elaborated on—what does “short term” mean? Presentation: 3/5 OK generally, but lacking in several key areas (biomass usage, proposed activities, costs). The proposal hasn’t made a compelling case that this will lead to benefits. --- (1) It is a very complete list of items that are addressed in this presentation. (2) It provides a good cost and actions description. (3) The program is best suited in large cities that will house urban bioreactors. The project plans to place it in sub-Saharan Africa. (4) The key benefits information is an inadequate explanation.
Aug 26, 2014
Great project. I wish you the best!. As I supported your proposal I would appreciate you support my proposal in Waste Management Contest, named 'REACC - Recycled Debris for Adaptation to Climate Change'. Regards!
Sep 3, 2014
- Proposal for small-scale cultivation of cyanobacteria in bioreactors. Proposal has not been updated since initial review. - Interesting idea, but who would carry it out, and what are the costs? Needs a lot more work. Maybe the proposer should come back next year with some more detail. - No improvements to second round of submissions. Earlier comments are noted here: (1) The proposal has a very complete list of items that are well addressed in this presentation. (2) It provides a good cost and actions description. (3) The program is best suited to large cities that will house urban bioreactors. The project plans to place it in sub-Saharan Africa. (4) The "key benefits" section contains an inadequate explanation.