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What's the deal with natural gas? It doesn't seem "renewable"; isn't it extracted just like petrol? Is it just that it burns cleaner? Doesn't burning it stil

What's the deal with natural gas? It doesn't seem "renewable"; isn't it extracted just like petrol? Is it just that it burns cleaner? Doesn't burning it still produce carbon dioxide?

jacquesm 9y ago
Yes, it burns cleaner (a lot cleaner, coal plants need scrubbers on the stacks). NG also is easier to transport (pipelines rather than hauling it with vehicles or boats) and does not cause the release of radioactive particles (which coal does do).
- maxerickson 9y ago
  Natural gas also results in significantly less C02 released per unit of energy produced. https://www.eia.gov/tools/faqs/faq.php?id=73&t=11 https://www.eia.gov/tools/faqs/faq.php?id=73&t=11
  - jessriedel 9y ago
    To save others a click: it's slightly less than a factor of two better. 214-228 lbs C02 per btu, vs. 117 for natural gas.
    - maxerickson 9y ago
      You also have to factor in the differences in the plants. So I guess it often works out to slightly more than a factor of two. The other side of it is that unburned coal doesn't leak into the air as a potent greenhouse gas the way methane does.
      - pacaro 9y ago
        The other side of the waste equation is also worse for coal. Fly ash is typically radioactive enough that if it were produced at a nuclear facility it would be categorized as nuclear waste. To be clear, burning coal concentrates the uranium and thorium that naturally occur in coal by a factor of about 10. There is still only a very small amount. Living within the stack shadow (~1km) of a coal fired plant only increases your exposure to background radiation by about 5%
  - cyberpunk 9y ago
    What about "biomass"? I've read that wood burning facilities are significantly worse than coal shops when it comes to emissions; a simple google could answer my question I know but it seems you're into this stuff so I'd like your take..
    - badosu 9y ago
      The emissions are counterbalanced by the fact that carbon was captured by those woods. Of course, assuming you aren't accounting emission due to the operation itself.
krschultz 9y ago
It's certainly cleaner as mentioned in the other comment. Another factor is that natural gas turbines can be turned on and off more quickly than coal fired plants. This is because a gas turbine is literally burning the gas in the turbine, it's akin to a jet engine on an airplane you can throttle up and down. A coal fired power plant is really a boiler that creates steam, and then the steam is fed through a turbine. Heating up all the water to make steam actually takes a long time. In an era of renewable energy sources (solar, wind) that fluctuate more unpredictably, having that "dispatchability" is really valuable. http://www.nrel.gov/docs/fy12osti/55433.pdf http://www.nrel.gov/docs/fy12osti/55433.pdf
- stygiansonic 9y ago
  This brings up a very important point. Electricity supply must be carefully balanced with demand and so that's why most regions have ISO (independent system operators) to facilitate the coordination needed to maintain system balance. Typically coal and nuclear power plants are "base" load stations, providing always-on capacity. It's not always possible to vary their output to match demand, so typically (natural) gas power plants are used to match the remaining variable load. The start up/shut down cycle for these plants is far less costly.
  - deleted 9y ago
    [deleted]
  - ciaranm 9y ago
    There's live stats for the UK's national grid. There's a couple of sites that show it, e.g. http://gridwatch.co.uk/ http://gridwatch.co.uk/ Really interesting to see. Britain also has the interesting culture of tea drinking in the evenings - almost all using electric kettles. I believe the grid uses hydro stations to cover the load of this. Typically peaks during breaks and/or after popular TV shows in the evening.
    - zigzigzag 9y ago
      That used to be the case, yes. Since the arrival of many-channel TV and changed viewing habits (e.g. lots more internet use) the advert-break-effect has lessened considerably.
ed_balls 9y ago
less CO2, NOX, sulfur dioxide, radioactive particles, PM10 and PM2.5
gwbas1c 9y ago
Natural gas releases significantly less carbon for the equivalent energy. It's also much cleaner. A gas stove is natural gas, and they exhaust right into the house. You'd never do that with coal.
seiferteric 9y ago
Natural gas is primarily methane (CH4) with about half the energy coming from burning hydrogen, compared to 100% coming from carbon in the case of coal, so you get about %50 CO2 for the same amount of energy produced.
- labster 9y ago
  I hope you mean that the energy from burning methane comes from breaking C—H bonds, not burning hydrogen gas.
  - syrrim 9y ago
    Breaking bonds requires input energy, rather than producing energy. Once the bonds are broken, you have free floating hydrogen and carbon. These can then form new bonds with oxygen, releasing energy as they do.
  - semi-extrinsic 9y ago
    I'm pretty sure that's what they meant. But actually, converting methane into H2 is a serious proposal for essentially eliminating CO2 emissions from NG usage. The idea is that you do this at centralised facilities, using various iterations on Steam Methane Reforming (SMR); this method takes CH4 and H2O as input and produces separated H2 and CO2 as output. SMR is already being done at large scale for H2 production (IIRC we would only have to scale it up by 100x), but currently the CO2 is mainly released back to the atmosphere. If instead one would store the CO2 permanently underground in old gas reservoirs and saline aquifers, NG would give us a mostly clean energy source. I really hope we will see this happen, but it depends a lot on government action...
    - twic 9y ago
      There's a nifty new method for extracting hydrogen from methane which involves bubbling it through molten tin: http://www.chemicalprocessing.com/articles/2015/researchers-crack-methane-cracking/ http://www.chemicalprocessing.com/articles/2015/researchers-... The carbon comes off as powder, which is easier to sequester than CO2 because you can just throw it in the bin.
Spooky23 9y ago
It's not renewable, but there's a ton of it. Gas also has very low particulate and other emissions. It's also more economical. Something like a coal or nuclear plant produces power whether you need it or not.
- ptaipale 9y ago
  Technically, nuclear is easily adjustable. Operators typically want to run nuclear at full capacity because the construction investment is a dominant part in the cost structure, i.e. you save very little of the cost if you produce less electricity, but there is no technical problem in using nuclear as adjustment power.
yuhong 9y ago
There is "methane cracking", which is probably the next step
alkonaut 9y ago
It's better than coal but in terms of CO2 it's the same.l (a factor .5 according to the article - which isn't insignificant) Gas can be extracted from renewable sources too, and that gas works in the same infrastructure so hopefully biogas will displace more of the NG production in the future.
nhaehnle 9y ago
Natural gas isn't renewable, but a natural gas infrastructure can actually contribute towards solving the energy storage problem. The idea is that surplus electricity from renewable energy is used to create hydrogen which is added to the natural gas grid and burned later in gas turbines when the demand exceeds the supply of renewables. A significant amount of hydrogen can be mixed in with natural gas without issues. For the longer term, people are also working on generating methane (CH4), which is the main component of natural gas, from electricity and CO2. Burning that would be carbon neutral as well.
Tade0 9y ago
It does, but about half that of coal. The reason for that is nearly half of the energy in burning natural gas comes from hydrogen(rather than carbon) atoms binding with oxygen.
ptaipale 9y ago
Natural gas is mostly fossil, but in my country (Finland), where total gas consumption is 26 TWh per year, the capacity for bio-generated gas (mostly from waste, e.g. processing of sewer waste) was 350 GWh a couple of years ago and is growing rapidly. So, currently around 1.5 % of methane gas is renewable. It is estimated that up to 10 TWh per year could be generated, which would bring the proportion to something like one third. From point of view of greenhouse gas emissions, the impact is quite large because methane produced by biological decomposition is a potent greenhouse gas, so having more of it burned in power plants is definitely good.

What's the deal with natural gas? It doesn't seem "renewable"; isn't it extracted just like petrol? Is it just that it burns cleaner? Doesn't burning it still produce carbon dioxide?

jacquesm 9y ago

Yes, it burns cleaner (a lot cleaner, coal plants need scrubbers on the stacks). NG also is easier to transport (pipelines rather than hauling it with vehicles or boats) and does not cause the release of radioactive particles (which coal does do).

maxerickson 9y ago
Natural gas also results in significantly less C02 released per unit of energy produced. https://www.eia.gov/tools/faqs/faq.php?id=73&t=11 https://www.eia.gov/tools/faqs/faq.php?id=73&t=11
- jessriedel 9y ago
  To save others a click: it's slightly less than a factor of two better. 214-228 lbs C02 per btu, vs. 117 for natural gas.
  - maxerickson 9y ago
    You also have to factor in the differences in the plants. So I guess it often works out to slightly more than a factor of two. The other side of it is that unburned coal doesn't leak into the air as a potent greenhouse gas the way methane does.
    - pacaro 9y ago
      The other side of the waste equation is also worse for coal. Fly ash is typically radioactive enough that if it were produced at a nuclear facility it would be categorized as nuclear waste. To be clear, burning coal concentrates the uranium and thorium that naturally occur in coal by a factor of about 10. There is still only a very small amount. Living within the stack shadow (~1km) of a coal fired plant only increases your exposure to background radiation by about 5%
- cyberpunk 9y ago
  What about "biomass"? I've read that wood burning facilities are significantly worse than coal shops when it comes to emissions; a simple google could answer my question I know but it seems you're into this stuff so I'd like your take..
  - badosu 9y ago
    The emissions are counterbalanced by the fact that carbon was captured by those woods. Of course, assuming you aren't accounting emission due to the operation itself.

krschultz 9y ago

It's certainly cleaner as mentioned in the other comment. Another factor is that natural gas turbines can be turned on and off more quickly than coal fired plants. This is because a gas turbine is literally burning the gas in the turbine, it's akin to a jet engine on an airplane you can throttle up and down. A coal fired power plant is really a boiler that creates steam, and then the steam is fed through a turbine. Heating up all the water to make steam actually takes a long time. In an era of renewable energy sources (solar, wind) that fluctuate more unpredictably, having that "dispatchability" is really valuable. http://www.nrel.gov/docs/fy12osti/55433.pdf http://www.nrel.gov/docs/fy12osti/55433.pdf

stygiansonic 9y ago
This brings up a very important point. Electricity supply must be carefully balanced with demand and so that's why most regions have ISO (independent system operators) to facilitate the coordination needed to maintain system balance. Typically coal and nuclear power plants are "base" load stations, providing always-on capacity. It's not always possible to vary their output to match demand, so typically (natural) gas power plants are used to match the remaining variable load. The start up/shut down cycle for these plants is far less costly.
- deleted 9y ago
  [deleted]
- ciaranm 9y ago
  There's live stats for the UK's national grid. There's a couple of sites that show it, e.g. http://gridwatch.co.uk/ http://gridwatch.co.uk/ Really interesting to see. Britain also has the interesting culture of tea drinking in the evenings - almost all using electric kettles. I believe the grid uses hydro stations to cover the load of this. Typically peaks during breaks and/or after popular TV shows in the evening.
  - zigzigzag 9y ago
    That used to be the case, yes. Since the arrival of many-channel TV and changed viewing habits (e.g. lots more internet use) the advert-break-effect has lessened considerably.

ed_balls 9y ago

less CO2, NOX, sulfur dioxide, radioactive particles, PM10 and PM2.5

gwbas1c 9y ago

Natural gas releases significantly less carbon for the equivalent energy. It's also much cleaner. A gas stove is natural gas, and they exhaust right into the house. You'd never do that with coal.

seiferteric 9y ago

Natural gas is primarily methane (CH4) with about half the energy coming from burning hydrogen, compared to 100% coming from carbon in the case of coal, so you get about %50 CO2 for the same amount of energy produced.

labster 9y ago
I hope you mean that the energy from burning methane comes from breaking C—H bonds, not burning hydrogen gas.
- syrrim 9y ago
  Breaking bonds requires input energy, rather than producing energy. Once the bonds are broken, you have free floating hydrogen and carbon. These can then form new bonds with oxygen, releasing energy as they do.
- semi-extrinsic 9y ago
  I'm pretty sure that's what they meant. But actually, converting methane into H2 is a serious proposal for essentially eliminating CO2 emissions from NG usage. The idea is that you do this at centralised facilities, using various iterations on Steam Methane Reforming (SMR); this method takes CH4 and H2O as input and produces separated H2 and CO2 as output. SMR is already being done at large scale for H2 production (IIRC we would only have to scale it up by 100x), but currently the CO2 is mainly released back to the atmosphere. If instead one would store the CO2 permanently underground in old gas reservoirs and saline aquifers, NG would give us a mostly clean energy source. I really hope we will see this happen, but it depends a lot on government action...
  - twic 9y ago
    There's a nifty new method for extracting hydrogen from methane which involves bubbling it through molten tin: http://www.chemicalprocessing.com/articles/2015/researchers-crack-methane-cracking/ http://www.chemicalprocessing.com/articles/2015/researchers-... The carbon comes off as powder, which is easier to sequester than CO2 because you can just throw it in the bin.

Spooky23 9y ago

It's not renewable, but there's a ton of it. Gas also has very low particulate and other emissions. It's also more economical. Something like a coal or nuclear plant produces power whether you need it or not.

ptaipale 9y ago
Technically, nuclear is easily adjustable. Operators typically want to run nuclear at full capacity because the construction investment is a dominant part in the cost structure, i.e. you save very little of the cost if you produce less electricity, but there is no technical problem in using nuclear as adjustment power.

yuhong 9y ago

There is "methane cracking", which is probably the next step

alkonaut 9y ago

It's better than coal but in terms of CO2 it's the same.l (a factor .5 according to the article - which isn't insignificant) Gas can be extracted from renewable sources too, and that gas works in the same infrastructure so hopefully biogas will displace more of the NG production in the future.

nhaehnle 9y ago

Natural gas isn't renewable, but a natural gas infrastructure can actually contribute towards solving the energy storage problem. The idea is that surplus electricity from renewable energy is used to create hydrogen which is added to the natural gas grid and burned later in gas turbines when the demand exceeds the supply of renewables. A significant amount of hydrogen can be mixed in with natural gas without issues. For the longer term, people are also working on generating methane (CH4), which is the main component of natural gas, from electricity and CO2. Burning that would be carbon neutral as well.

Tade0 9y ago

It does, but about half that of coal. The reason for that is nearly half of the energy in burning natural gas comes from hydrogen(rather than carbon) atoms binding with oxygen.

ptaipale 9y ago

Natural gas is mostly fossil, but in my country (Finland), where total gas consumption is 26 TWh per year, the capacity for bio-generated gas (mostly from waste, e.g. processing of sewer waste) was 350 GWh a couple of years ago and is growing rapidly. So, currently around 1.5 % of methane gas is renewable. It is estimated that up to 10 TWh per year could be generated, which would bring the proportion to something like one third. From point of view of greenhouse gas emissions, the impact is quite large because methane produced by biological decomposition is a potent greenhouse gas, so having more of it burned in power plants is definitely good.