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Oslo is powering their city by putting black ash into the air, which absorbs heat from sunlight, slightly increasing the amount of energy in all of our environm

Oslo is powering their city by putting black ash into the air, which absorbs heat from sunlight, slightly increasing the amount of energy in all of our environmental systems. The place is powered by externalities, just like China. This solution is no better than coal-generated electricity, and this feel-good article is no more useful than clean-coal articles.

danso 14y ago
Don't some of the modern systems have processes that mitigate the released ash? I found their recycling systems to be even more impressive sounding than the garbage incineration
jre 14y ago
My understanding is that the garbage would be burnt anyway so better use it for heating.
jessriedel 14y ago
But the ash doesn't stick around, does it? Do you have an order-of-magnitude estimate for the heating effects of the ash? I'm guessing it's trivial compared to carbon offset.
- tomsaffell 14y ago
  There seems to be some debate about whether particulate matter has a net-warming or net-cooling effect. It's difficult to estimate empirically, because there are so many uncontrolled variables. http://en.wikipedia.org/wiki/Global_dimming http://en.wikipedia.org/wiki/Global_dimming http://en.wikipedia.org/wiki/Global_cooling#Aerosols http://en.wikipedia.org/wiki/Global_cooling#Aerosols
- niels_olson 14y ago
  Ash represents incomplete combustion. I'm pretty the engineers are motivated to ensure the ash is a minor waste product compared the gasses, but somebody should check me on that.
riveteye 14y ago
Hmm. I was under the impression that burning garbage is different in that you are burning carbon that is already in play in the carbon cycle system - unlike burning coal, which without human intervention would never be introduced into the environment at such a rapid pace. I could be wrong! I was disappointed by the lack of an explanation, or even links to background on the science of this process. Just a puff/fluff piece IMHO.
- jlgreco 14y ago
  It would really depend on what is being burnt. If it is primarily food waste, paper products, natural fibers, wood, etc.. then yeah; all of that carbon was already "in the system". If they are burning lots of garbage made from petrochemicals then that garbage is basically just another fossil fuel. As I understand it, the real issue with "clean coal" is not the soot but rather the CO2. Depending on what this garbage actually is, the CO2 problem isn't really a problem in this case.
  - stephengillie 14y ago
    I found a case study about Oslo's waste management strategy: http://www.c40cities.org/c40cities/oslo/city_case_studies/waste-management-system http://www.c40cities.org/c40cities/oslo/city_case_studies/wa... The study emphasizes their focus on composting for food products and recycling everything else, so a minimum of waste needs to be incinerated or dumped. Also, Oslo closed their landfill in 2007, and it seems they burn the residual gasses (methane?) for electricity, if not burning all of their old trash. The report focuses on home recycling requirements, but does not mention commercial or industrial waste, which are by far larger generators of waste. So, it seems likely that the incinerated waste is not "in-system".
    - jlgreco 14y ago
      Surely burning that methane is "in-system". Methane has a 20-year GWP of 72 and, unless my chemistry is far more rusty than I think it is, 1 mol of methane will burn with oxygen to form 1 mol of CO2. From a global warming standpoint, it would actually be wildly irresponsible to not burn that methane. In fact this seems to be the basis for the EPA's "Landfill Methane Outreach Program".
frenchman_in_ny 14y ago
"This solution is no better than coal-generated electricity" I'm not sure that's true at all. The only way a waste-to-energy plant can import waste from cross-borders is by having R1 status, R1 being a measure of energy recovery from the municipal waste that is burned [1]. On top of this, the plants (generally) recycle the plastic / metal that isn't burned, sell the fuel ash (to stabilize roads, etc), cogenerate steam from additional energy production, and either sell back to the municipalities the natural gas generated by the organic waste digestors or use it to generate additional electricity. [1] http://www.cewep.eu/information/publicationsandstudies/statements/ceweparticles/m_562 http://www.cewep.eu/information/publicationsandstudies/state...

danso 14y ago

Don't some of the modern systems have processes that mitigate the released ash? I found their recycling systems to be even more impressive sounding than the garbage incineration

jre 14y ago

My understanding is that the garbage would be burnt anyway so better use it for heating.

jessriedel 14y ago

But the ash doesn't stick around, does it? Do you have an order-of-magnitude estimate for the heating effects of the ash? I'm guessing it's trivial compared to carbon offset.

tomsaffell 14y ago
There seems to be some debate about whether particulate matter has a net-warming or net-cooling effect. It's difficult to estimate empirically, because there are so many uncontrolled variables. http://en.wikipedia.org/wiki/Global_dimming http://en.wikipedia.org/wiki/Global_dimming http://en.wikipedia.org/wiki/Global_cooling#Aerosols http://en.wikipedia.org/wiki/Global_cooling#Aerosols
niels_olson 14y ago
Ash represents incomplete combustion. I'm pretty the engineers are motivated to ensure the ash is a minor waste product compared the gasses, but somebody should check me on that.

riveteye 14y ago

Hmm. I was under the impression that burning garbage is different in that you are burning carbon that is already in play in the carbon cycle system - unlike burning coal, which without human intervention would never be introduced into the environment at such a rapid pace. I could be wrong! I was disappointed by the lack of an explanation, or even links to background on the science of this process. Just a puff/fluff piece IMHO.

jlgreco 14y ago
It would really depend on what is being burnt. If it is primarily food waste, paper products, natural fibers, wood, etc.. then yeah; all of that carbon was already "in the system". If they are burning lots of garbage made from petrochemicals then that garbage is basically just another fossil fuel. As I understand it, the real issue with "clean coal" is not the soot but rather the CO2. Depending on what this garbage actually is, the CO2 problem isn't really a problem in this case.
- stephengillie 14y ago
  I found a case study about Oslo's waste management strategy: http://www.c40cities.org/c40cities/oslo/city_case_studies/waste-management-system http://www.c40cities.org/c40cities/oslo/city_case_studies/wa... The study emphasizes their focus on composting for food products and recycling everything else, so a minimum of waste needs to be incinerated or dumped. Also, Oslo closed their landfill in 2007, and it seems they burn the residual gasses (methane?) for electricity, if not burning all of their old trash. The report focuses on home recycling requirements, but does not mention commercial or industrial waste, which are by far larger generators of waste. So, it seems likely that the incinerated waste is not "in-system".
  - jlgreco 14y ago
    Surely burning that methane is "in-system". Methane has a 20-year GWP of 72 and, unless my chemistry is far more rusty than I think it is, 1 mol of methane will burn with oxygen to form 1 mol of CO2. From a global warming standpoint, it would actually be wildly irresponsible to not burn that methane. In fact this seems to be the basis for the EPA's "Landfill Methane Outreach Program".

frenchman_in_ny 14y ago

"This solution is no better than coal-generated electricity" I'm not sure that's true at all. The only way a waste-to-energy plant can import waste from cross-borders is by having R1 status, R1 being a measure of energy recovery from the municipal waste that is burned [1]. On top of this, the plants (generally) recycle the plastic / metal that isn't burned, sell the fuel ash (to stabilize roads, etc), cogenerate steam from additional energy production, and either sell back to the municipalities the natural gas generated by the organic waste digestors or use it to generate additional electricity. [1] http://www.cewep.eu/information/publicationsandstudies/statements/ceweparticles/m_562 http://www.cewep.eu/information/publicationsandstudies/state...