Breakthrough solar cell captures CO2 and sunlight, produces burnable fuel • Hacker News Board

Re: Breakthrough solar cell captures CO2 and sunlight, produces burnable fuel

#61

Post by kevinalexbrown » Sat, Jul 30, 2016, 10:26 PM UTC

runeks wrote: post #9

This is wonderful! We're surrounded by life forms that turn water, CO2 and sunlight into energy. I figure there must be some way to harness this process. I wonder how much power a large tree takes in from its leaves. If we could interface with its root system, perhaps we could extract newly created starch, and either store it or burn it off. Image a huge concrete power plant with large trees growing out of it.

It's actually a major approach under the name biomass. Despite releasing carbon when wood is burned, the tree has taken in significant CO2 over the course of its life. In addition, decomposing wood byproducts are going to release carbon anyway as they decompose, I believe. Places with excess wood byproduct can generate power onsite.

It's not going to replace other power sources, but it is commonly done.

Re: Breakthrough solar cell captures CO2 and sunlight, produces burnable fuel

#62

Post by kevinalexbrown » Sat, Jul 30, 2016, 10:27 PM UTC

Animats wrote: post #35

"Nanotechnology" again. It's just surface chemistry, people. It's nice that they can do this in the lab, but as usual, the PR is excessive. "The ability to turn CO2 into fuel at a cost comparable to a gallon of gasoline would render fossil fuels obsolete." At least get to pilot plant stage before issuing statements like that. Especially since UC Berkeley announced a similar breakthrough last year.[1] Wikipedia points…

The press release at least attempted to answer some of your 'usual questions'.

Re: Breakthrough solar cell captures CO2 and sunlight, produces burnable fuel

#63

Post by jrapdx3 » Sat, Jul 30, 2016, 10:28 PM UTC

CoryG89 wrote: post #54

jrapdx3 wrote: post #42

Earlier quoted context omitted.

Don't know of course, though it appears to be a "diverse" group who worked on the project. The salient point is Trump has made it clear he was talking about illegal entrants and delaying entry for individuals coming from areas where terrorism is endemic, until a vetting process is established. There are a great number of professionals from Muslim countries regularly admitted who contribute to American society and cul…

> and delaying entry for individuals coming from areas where terrorism is endemic, until a vetting process is established. I hate to even further the discussion on this off-topic subject, but the above is simply not true. Here is the official statement (still published in it's original form) directly from Donald Trump's website: > Donald J. Trump is calling for a total and complete shutdown of Muslims entering the Un…

Well, it appears to be policy in evolution. I based my comment on what Trump has said in his most recent appearances, and quite credibly that's not yet reflected in the online published material.

Realistically campaigns of all stripes frequently change positions and policy is hardly set in stone. I expect we'll witness numerous "corrections" from all candidates as the election season moves along.

BTW during the Republican and Democrat conventions just concluded, both candidates mentioned policies of this kind. It might be worth the effort to listen to both party's candidates' acceptance speeches since that would represent their current positions.

Re: Breakthrough solar cell captures CO2 and sunlight, produces burnable fuel

#64

Post by lifeisstillgood » Sat, Jul 30, 2016, 10:29 PM UTC

karma_vaccum123 wrote: post #60

azernik wrote: post #58

Earlier quoted context omitted.

Because we care about rigor and accuracy in this forum, and would prefer to be aware if and how the article title and content don't reflect reality. If these comments bore you, skip them.

There is nothing rigorous about the ongoing fantasy that random HN commenters know things that no one else does.

I have regularly found that random HN commenters often turn out to have years of professional experience in the industries they are commenting on. Its one of the fun parts of reading HN.

Re: Breakthrough solar cell captures CO2 and sunlight, produces burnable fuel

#65

Post by 67726e » Sat, Jul 30, 2016, 10:31 PM UTC

Add unsweetened shebenchnach. C

Re: Breakthrough solar cell captures CO2 and sunlight, produces burnable fuel

#66

Post by mchannon » Sat, Jul 30, 2016, 10:36 PM UTC

imaginenore wrote: post #10

mchannon wrote: post #5

In addition to lack of performance numbers, they misstate the amount of sunlight hitting earth by a factor of 10- it's supposed to be 1000 W/m2, not 100.

100w is closer to reality for most places. 1000W per meter squared is an ideal case for some near-equatorual desert at noon with very clean air.

Sorry, no.

100W/m2 is highly unusual for any place on Earth. Take the most overcast midday conditions you can imagine and they'll exceed 100W/m2 by a comfortable margin. That can be in Germany, Canada, Colombia, or Antarctica. If it's sunny, it's very close to 1000, no matter where you are. Partly cloudy can even exceed 1000, since clouds can reflect additional sunlight onto the ground.

Then there's of course nighttime, which is 0 W/m2.

You will have to work really hard to find conditions of 100 W/m2, which is why they standardize on 1000, itself quite straightforward to find anywhere on Earth.

"10% sounds right" is specious.

Re: Breakthrough solar cell captures CO2 and sunlight, produces burnable fuel

#67

Post by Gargoyle » Sat, Jul 30, 2016, 10:39 PM UTC

lifeisstillgood wrote: post #64

karma_vaccum123 wrote: post #60

Earlier quoted context omitted.

There is nothing rigorous about the ongoing fantasy that random HN commenters know things that no one else does.

I have regularly found that random HN commenters often turn out to have years of professional experience in the industries they are commenting on. Its one of the fun parts of reading HN.

But it'd be great to have an "ignore user" function for those few who just google their skepticism.

Re: Breakthrough solar cell captures CO2 and sunlight, produces burnable fuel

#68

Post by detaro » Sat, Jul 30, 2016, 10:46 PM UTC

mchannon wrote: post #66

imaginenore wrote: post #10

Earlier quoted context omitted.

100w is closer to reality for most places. 1000W per meter squared is an ideal case for some near-equatorual desert at noon with very clean air.

Sorry, no. 100W/m2 is highly unusual for any place on Earth. Take the most overcast midday conditions you can imagine and they'll exceed 100W/m2 by a comfortable margin. That can be in Germany, Canada, Colombia, or Antarctica. If it's sunny, it's very close to 1000, no matter where you are. Partly cloudy can even exceed 1000, since clouds can reflect additional sunlight onto the ground. Then there's of course nightti…

For Germany the yearly average is 110 W/m² or so. Clear summer days go to >1000, but nights and bad weather days push the average down. Maybe they meant that in the article, maybe they missed a zero.

If they meant it, it seems like an odd comparison without data if the cell scales with power. If it doesn't, it can't properly utilize bright days and would miss out on most of that average power.

Re: Breakthrough solar cell captures CO2 and sunlight, produces burnable fuel

#69

Post by tim333 » Sat, Jul 30, 2016, 10:56 PM UTC

skriticos2 wrote: post #46

runeks wrote: post #9

This is wonderful! We're surrounded by life forms that turn water, CO2 and sunlight into energy. I figure there must be some way to harness this process. I wonder how much power a large tree takes in from its leaves. If we could interface with its root system, perhaps we could extract newly created starch, and either store it or burn it off. Image a huge concrete power plant with large trees growing out of it.

There is a simple way: 1. Plant tree 2. Wait 20 years 3. Chop tree 4. Burn tree in steam engine and generate electricity. However, that's a long time for a relatively small amount of energy (not even counting logistics losses here). Most trees are just not very efficient at converting solar energy/CO2 into fuel (wood). There are better results being looked in with algae that might result in fuel some time, but it's s…

Algenol looked quite promising. Apparently they got 8000 gal/acre/year from their trial. Somehow they never quite get to commercial production though. http://www.ethanolproducer.com/articles/12005/green-expectat...

Re: Breakthrough solar cell captures CO2 and sunlight, produces burnable fuel

#70

Post by mistercow » Sat, Jul 30, 2016, 10:56 PM UTC

Animats wrote: post #35

"Nanotechnology" again. It's just surface chemistry, people. It's nice that they can do this in the lab, but as usual, the PR is excessive. "The ability to turn CO2 into fuel at a cost comparable to a gallon of gasoline would render fossil fuels obsolete." At least get to pilot plant stage before issuing statements like that. Especially since UC Berkeley announced a similar breakthrough last year.[1] Wikipedia points…

>At least get to pilot plant stage before issuing statements like that.

To be fair, making statements like that can help you get to that stage. It sucks that this is how it works, but playing the game is understandable.