Major Advance in Artificial Photosynthesis Poses Win/Win for the Environment | Hacker News Reader

Major Advance in Artificial Photosynthesis Poses Win/Win for the Environment

newscenter.lbl.gov

126 pointsvelodrome10 comments

It's an interesting diversion, and useful beyond just carbon sequestration - I love how this is a combination of machine/organic lifeforms: "nanowires harvest solar energy and deliver electrons to bacteria, where carbon dioxide is reduced and combined with water for the synthesis of a variety of targeted, value-added chemical products.”" - (Bacterial Cyborgs?) - but the sooner we transition to a solar based energy economy, the sooner we can stop doing inane things like burning coal for energy.

Note also, they have a long, long way to go before this becomes even remotely commercially viable. "With this approach, the Berkeley team achieved a solar energy conversion efficiency of up to 0.38-percent for about 200 hours under simulated sunlight, which is about the same as that of a leaf."

So, they are about 40 years behind where Solar energy is today.

Still cool though.

Keep in mind that converting solar energy to chemical energy (what plants do, and what these researchers have done) is a much harder problem than converting solar energy to electrical energy directly.

Also, the main result of this work seems to be not energetic efficiency, but the production of flexible precursor chemicals.

Love the idea of orchards of trees producing precursors. Makes me think of the maple syrup producers we visit every spring, forests with a huge web of surgical rubber tubing linking the trees to a central boiling cabin. But instead of sweet sweet maple syrup these make pharmaceuticals. :D

But plants already convert solar energy to chemical storage at efficiencies of 1-3%. Up to 10% for algae (higher per-hectare yields are based on added energy). It turns out that existing artificial proceses might already get close to this via electrolysis, carbon separation from seawater,and Fischer-Tropsch synthesis. But for raw efficiency, it's really hard to beat plants.

The other problem is that humans are already appropriating 20-40% of all primary production. So while plants are good at what they do, we're already leaning on them really hard.

Unless humans can come up with methods which are 1) complimentary to existing plant activity (e.g., they don't compete for the same space, water, and/or minerals), and that's 2) roughly as efficient or better, we look kind of stuck.

You have to keep in mind that they have a) positive (if small) efficiency b) capture CO2 c) produce chemicals instead of electricity

If you don't compare this to photovoltaics and look at carbon capture instead (which consumes energy, thus reducing efficiency of the power plant) then this already is a win.

Not to mention that the CO2 captured isn't just in liquid form - which is not trivial to store permanently - but in a useful, easy-to-handle form.

These guys in Israel have been developing something very similar for a while now: http://www.newco2fuels.co.il/

"NewCO2Fuels innovative technology converts CO2 and H2O into syngas and from it synthetic transportation fuels or chemicals using present available technologies. The end products are competitive with current market prices with no incentives thanks to the very high efficiency rate of the NCF system."

I stumbled on them while Googling just last week.

Great to see this kind of R&D being done. I'd love to read a comparison of the various CO2 sequestration technologies out there.

Minus the photosynthesis part.

Anyone know of commentary beyond this lab press release?

Yes, please! Someone with more knowledge on the subject please enlighten us! It looks really cool to me, but I don't know enough to start a conversation, heh!

It's interesting work. I wonder how much input energy is required to mine, refine, and build the required silicon and titanium oxide nanowires? If it's less than 1 to 1 with the lifetime output, then the tech will need more work to be a real solution. Hopefully it scales.

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