4 ms·

This appears to be a based on a paper from last year. http://science.sciencemag.org/content/351/6268/74 http://science.sciencemag.org/content/351/6268/74 While

This appears to be a based on a paper from last year. http://science.sciencemag.org/content/351/6268/74 http://science.sciencemag.org/content/351/6268/74 While good and interesting work, there's a lot left to do. They're using cysteine as a reductant, so not all of the energy is coming from light. Furthermore while the system uses 90% of the cysteine and 80% of blue light, it is only 2% efficient with broad spectrum (sun-like) lighting. Even that well only under dim lighting. Edit: Here's a group that's developed a system that's 5 times as efficient and only uses CO2 and water as feedstock rather than cysteine and cadmium. http://science.sciencemag.org/content/352/6290/1210 http://science.sciencemag.org/content/352/6290/1210

subnaught 9y ago
That's an apples-and-oranges comparison. The system you cite differs from the one under discussion in several ways; the most important of which are: 1. The cited system does not include a light-harvesting component. It merely postulates that the required energy could be generated from photovoltaics. This would introduce additional cost and complexity along with an efficiency hit. 2. The cited system comprises a bacterium in conjuction with an electrode-supported catalyst, whereas the system under discussion is solely an engineered bacterium. Finally, it is not correct to refer to cadmium and cysteine as feedstocks. They are components of the catalyst, and they are not consumed during catalysis. The only feedstocks for both systems are CO2 and water.
- spqr0a1 9y ago
  You're right that Liu's paper does use external electrodes. And as for Sakimoto's paper it's true that the cadmium should be reusable indefinitely, but if you read the second page it's clear than cysteine is consumed in stoichiometric amounts. I'd be excited to hear about more recent work which improves upon this and would be happy to be corrected.

subnaught 9y ago

That's an apples-and-oranges comparison. The system you cite differs from the one under discussion in several ways; the most important of which are: 1. The cited system does not include a light-harvesting component. It merely postulates that the required energy could be generated from photovoltaics. This would introduce additional cost and complexity along with an efficiency hit. 2. The cited system comprises a bacterium in conjuction with an electrode-supported catalyst, whereas the system under discussion is solely an engineered bacterium. Finally, it is not correct to refer to cadmium and cysteine as feedstocks. They are components of the catalyst, and they are not consumed during catalysis. The only feedstocks for both systems are CO2 and water.

spqr0a1 9y ago
You're right that Liu's paper does use external electrodes. And as for Sakimoto's paper it's true that the cadmium should be reusable indefinitely, but if you read the second page it's clear than cysteine is consumed in stoichiometric amounts. I'd be excited to hear about more recent work which improves upon this and would be happy to be corrected.