skosch

You're correct, that was sloppy wording on my part.

Because it's not a one-to-one conversion. See e.g. https://en.wikipedia.org/wiki/Second-harmonic_generation

The idea is to direct all of the nanotube-emitted light onto the PV cells, so hopefully you won't see anything. Citing the Rice article:

> Because electrons in nanotubes can only travel in one direction, the aligned films are metallic in that direction while insulating in the perpendicular direction, an effect Naik called hyperbolic dispersion. Thermal photons can strike the film from any direction, but can only leave via one.

The article doesn't provide very much detail, but it's absolutely possible to absorb multiple low-energy photons and emit fewer higher-energy ones, see e.g. https://en.wikipedia.org/wiki/Second-harmonic_generation – and apparently carbon nanotubes can do this as well.

Hot things glow. Medium hot things (like you) emit lots of infrared light. Really hot things (like lightbulbs) emit infrared and visible light. Ridiculously hot things (like the sun) emit infrared, visible light, and higher-energy radiation (UV etc.).

The exact details depend on the chemical composition of the material, but for a simple model, check out https://en.wikipedia.org/wiki/Black-body_radiation

You're confused – heat isn't being converted into anything. The article conflates the words "heat" and "infrared radiation", which are not at all the same thing.

As a rule, everything around you glows – in other words, it emits photons. Some infrared ones, some visible ones, some ultraviolet (or even higher-frequency) ones. How much of each depends on the temperature of the material. Most things (e.g. you) are too cold to be visibly glowing, but they still emit plenty of infrared radiation.

Now, standard solar cells convert visible photons into electricity. Any incoming infrared photons, however, aren't strong enough to kick any electrons loose, so they go to waste. Here, the researchers used carbon nanotubes to absorb the wasted infrared photons. This heats up the nanotubes, which then emit visible photons, which then increase electricity generation.

There is no way to convert heat to electricity directly, unfortunately. However, you can get small amounts of electricity out of temperature differences: https://en.wikipedia.org/wiki/Thermoelectric_effect

Huh? The Wikipedia article you linked puts the moon into

> Unrestricted Category V: “Earth-return missions from bodies deemed by scientific opinion to have no indigenous life forms.”

You need to look beyond just US corn. Crop yields need to continue increasing globally just to keep up with population growth, which going to be a significant challenge. At the same time, farmland is being lost to urbanization and desertification every single day. On top of that, weeds and pests are developing resistance to chemicals, and pollinating insects are dying off rapidly. Plus, GMO notwithstanding, conventional intensification methods are running into diminishing returns. So: farming ain't getting any easier.

Now, enter climate change. Droughts are bad. Downpours (cf. rainiest year) are arguably worse, because they accelerate soil erosion. Many places have lost half or more of their arable soil over the past half century, and rebuilding soil takes many, many years. No soil, no harvest.

So I don't share your optimism. Perhaps there are high tech solutions to all of the above problems, but they're (currently) too expensive for most of the world.

Well of course – almost nobody is really campaigning for independence. HK is very much dependent on the mainland, and that's understood. The demands are much more narrow: for the extradition bill to be scrapped, for Carrie Lam to step down, for elections to be free and fair, etc.

Yeah, this absolutely crucial piece of information is missing from most articles like this one, a journalistic failure I find incomprehensible.

Anyways, the Woods Hole Research center claims that boreal forest fires are not included in current climate models, and are likely to exacerbate the problem: http://whrc.org/wp-content/uploads/2018/11/PB_wildfires.pdf

Consider using a cookie for that purpose. I was looking for the calculator everywhere until I realized I had to enter my email first. That's a pretty big trust hurdle – no thanks.

I suggest you let people use the calculator freely, and when I enter e.g. "4 transatlantic flights per year" then you show me what that sin translates to specifically for one of your offset projects, e.g. "1000 briquettes" (with photos, of course). Personally speaking, that would make me pay up.

Oh, and the 20% fee is really problematic. I'd like to see a pay-what-I-want slider where I can adjust the percentage. The slider minimum would be set to min(0.2*x, $10) or some other reasonable amount, and you can calibrate that function to maximize donations.

Correct – more effective terms are climate crisis, climate chaos, climate emergency.

They aren't typically found in nature in the form in which we consume them. They require human processing (even if it's much less processing than what goes into making a frozen pizza).

Wild speculation: I wonder whether loudness is actually a design goal, to make the dryer appear more powerful. A sizable number of people are skeptical of electric vehicles, because they perceive an earth-shaking vroooom to be an essential part of the driving experience. Could someone with industry experience chime in?

You can look at the issue however you want, but at the end of the day somebody is going to have to pay for the renewable energy and carbon sequestration tech.

We can fund them with taxpayer money, which means the average Joe pays, and politicians pick winning (or losing) technologies.

Or we can make the polluters fund them, and let the invisible hand pick the best technologies.

I find the second option much more attractive. And Nobel-prize winning economists agree: https://www.nytimes.com/2018/10/08/business/economic-science...

I don't know about France, but this model is now reality in (at least part of) Canada, and the US has a bill before the House [0]. It's the only politically viable way of implementing carbon pricing.

[0] https://energyinnovationact.org

> "Paying for the damage" is this some kind of joke? What about all the other polluters? Shipping? Coal plants?

Right – tax them too, and distribute the revenue back to households. That way it's not a regressive tax, but a wealth transfer from heavy polluters to regular folks who are bearing the indirect costs of the climate crisis.

All of this has been studied and modeled extensively. It's called elasticity of demand. The fact that professional trading firms are selling airline stock, pushing the price down, shows you that yes, this will indeed have an effect.

Carbon taxes are the most efficient way to let the market work out technical solutions to the climate crisis. Period.

If you're worried about regressive taxation, check out the fee-and-dividend model, where all revenue is returned to households [0]. This means that for most "regular" people, the carbon tax is actually a tax credit – because most of the pollution is caused by the excessive consumption by rich households.

There is actually a bill before the House now that has a non-zero chance of passing.

[0] https://citizensclimatelobby.org/carbon-fee-and-dividend/

Carbon pricing, carbon pricing, carbon pricing. No other approach will allow technical solutions to emerge faster.

If you want to do something about climate change, talk to your politicians about carbon pricing. In the US there is finally a bill before the House now: https://citizensclimatelobby.org/energy-innovation-and-carbo...

(Also: plant trees, go vegan, fly less. But first and foremost make polluting expensive.)

Good question. The answer lies in multilateral agreements (Paris etc.) and in so-called Border Carbon Adjustments. The latter have to be implemented carefully so as not to violate any WTO rules [0], but it's possible.

[0] https://www.brookings.edu/wp-content/uploads/2018/07/TPC_201...

> Trees readily plant themselves in areas they are well adapted to.

I am very skeptical if that's true – see formerly forested areas like Iceland, Brazil, etc. It's not easy for a single sapling to grow into a tree, even if the conditions are right. That's why companies like Afforestt exist [0].

[0] http://www.afforestt.com/

Absolutely true. And tree planting appears (to me) to be an underappreciated philanthropic cause area. This study could help change that.

Interesting – we need more of such studies.

Check out Drawdown [0] for other interventions with quantified costs/benefits.

Economists widely agree that carbon pricing is the most effective way to fix climate change [1], and fee-and-dividend implementations are the most viable politically (there's a bill before Congress now [2]).

[0] https://www.drawdown.org/

[1] https://www.nytimes.com/2018/10/08/business/economic-science...

[2] https://citizensclimatelobby.org/energy-innovation-and-carbo...

The range matters – had they found 10 serial numbers between 100000 and 101000, would the mean still be a meaningful estimate of the production rate? In this case, the author just tacitly assumes the minimum to be zero.

Another favourite of mine is mpsyt – a terminal interface for youtube-dl. I stream music for hours without ever getting ads or even having to have Youtube open in the browser.

I'm curious why they use capsules of fine powder, instead of glued/sintered pellets. Perhaps you can provide some insight?

"Learning" here means averaging over many rollouts (i.e. simulation runs) of a policy. Naturally, time only increases in those runs, as you require.

I had no idea what this did until I watched the video.

Suggestion: let people play with the map customization tool directly on the landing page, then charge them for changing the date/location and for hi-res exports.

I agree with the sentiment, if not with the needlessly aggressive wording. Also, the spelling you're looking for is hordes, not hoards.