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Entrepreneurs Fight Air Pollution With CO2-Reducing 'CityTrees' (cnn.com)
CNN is reporting on "CityTree", a unique 10-foot tall mobile installation which removes pollutants from the air." An anonymous reader quotes their report:
Berlin-based Green City Solutions claims its invention has the environmental benefit of up to 275 actual trees. But the CityTree isn't, in fact, a tree at all -- it's a moss culture. "Moss cultures have a much larger leaf surface area than any other plant. That means we can capture more pollutants," said Zhengliang Wu, co-founder of Green City Solutions.
The huge surfaces of moss installed in each tree can remove dust, nitrogen dioxide and ozone gases from the air. The installation is autonomous and requires very little maintenance: solar panels provide electricity, while rainwater is collected into a reservoir and then pumped into the soil... "We also have pollution sensors inside the installation, which help monitor the local air quality and tell us how efficient the tree is." Wu said. Its creators say that each CityTree is able to absorb around 250 grams of particulate matter a day and contributes to the capture of greenhouse gases by removing 240 metric tons of CO2 a year... Wu also argued that the CityTree is just one piece of a larger puzzle. "Our ultimate goal is to incorporate technology from the CityTree into existing buildings," he said.
So far they've installed 20 CityTrees -- each of which costs about $25,000.
The huge surfaces of moss installed in each tree can remove dust, nitrogen dioxide and ozone gases from the air. The installation is autonomous and requires very little maintenance: solar panels provide electricity, while rainwater is collected into a reservoir and then pumped into the soil... "We also have pollution sensors inside the installation, which help monitor the local air quality and tell us how efficient the tree is." Wu said. Its creators say that each CityTree is able to absorb around 250 grams of particulate matter a day and contributes to the capture of greenhouse gases by removing 240 metric tons of CO2 a year... Wu also argued that the CityTree is just one piece of a larger puzzle. "Our ultimate goal is to incorporate technology from the CityTree into existing buildings," he said.
So far they've installed 20 CityTrees -- each of which costs about $25,000.
By the way, surface area is irrelevant if there isn't air flow past the surface, like there would be for an actual tree.
Particulate emissions and NO2 levels are largely local problems, especially when you look at health effects versus distance from source. You should want to clean up air in cities because there are lots of harmful emissions there, and because a lot of people live there. Especially in developing nations, along with China and India, it's wildly expensive to adopt the kind of environmental controls that the US and Europe use. I'm not sure that this gadget provides $25,000 worth of benefit, but I agree with the overall idea.
this shouldnt be troll. everything he described is in fact an accurate assessment of climate change.
have you seen my sig? there are many others like it but none that are the same
I see this as part of the solution not a fix to the problem.
Global warming is a big problem there isn't a magic bullet to fix the problem as there isn't one source that caused it.
The building of cities has caused a lot of deforestation and this is one of the factors in the problem. So if we have condense ways of cleaning the air in cities we can still keep the advantage of the concrete cities while adding the benefit of plant life to help reduce carbon.
Even if cities were plastered with these thing it isn't enough. But with combination of other changes such as moving to cleaner energy plants. More energy efficient transportation. We really slow down global climate change enough for the rest of the earth to heal from it, without having to make life changing sacrifices.
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
> There is no reason to locate CO2 consuming moss in any particular location
> So far they've installed 20 CityTrees -- each of which costs about $25,000.
The reason is to part idiots and their money.
When "doing something something green" is more important than doing something effective there'll always be some dimwit who falls for stuff like this.
We wouldn't claim that we did that to the other planets because your assertion is complete bullshit.
I hate to be the bearer of bad news, but something isn't true just because you thought of it.
You HAD to pick ozone as part of your post? It was a huge problem a few decades ago. Because the world globally decided to ban CFCs usage, it is no longer a major problem. Thou it is still in the process of repairing itself. If we go back to using CFCs, we can mess it up again in 2-3 decades. Sooner since we have so much more industry.
It's pretty much THE perfect example of how humans can easily impact climate change on a global level AND also solve it if they approach it scientifically!
"This is why Trump won the election, instead of trying to actually debate, you just immediately jump to insulting the poster for being stupid instead of actually trying to convince them of your side. The left might be surprised at the number of people they could persuade if they actually debated people"
The "left" has spent more than 40 years on that failed strategy - and they keep trying. FYI, the Glo-bull Warming Chinese Hoax poster child, James Hansen, is a long time REPUBLICAN and reluctant speaker who only stepped up to the plate because he felt not enough was being done, that the science wasn't being communicated, because he feared for the future of his children, and now his grandkids and thought that someone from the right who was also a scientist might be able to make a better case, to get opponents to listen to reason.
Pain is merely failure leaving the body
Photosynthesis does: CO2 + Water => Sugar + O2...then the plant takes that sugar and turns it into biomass by converting it to starches and structural materials for the plant itself.
Carbon has a molecular weight of 12 and Oxygen is 16...so CO2 is 25% carbon by weight. So to absorb 240 tons of CO2 per year - it's got to be generating (at a minimum) 60 tons of extra plant material per year - and more likely (because dead/living moss isn't all carbon) it's at least twice that.
There is only just so much space in that concrete container - which means that a literal truckload of dead/living moss has to be removed from it every single week! Then, that biomass has to be disposed of in some way that doesn't simply re-release it into the atmosphere when it decays...you'd have to bury it or something.
This is a ridiculous claim - it can't possibly be true. Even 24 tons a year wouldn't be credible - and 2.4 tons a year would seem high...the entire installation would haves to double in size every year to keep up even that more modest amount.
What I'm sure happened here is that it's plausible that the moss has vastly more surface area than a tree - but moss is much more slow-growing than trees are - so the amount of CO2 it absorbs cannot possibly be as much per-unit-area as the leaves of a tree. So I'm betting that they did all of their math from surface area alone - and didn't stop to think beyond that.
This is B.S.
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