US Emission Reductions Could Lower Temperature by 0.3 Degrees F by 2100

This article will estimate the temperature effect by 2100 of the US emission reductions from a business-as-usual model for the effects of climate change.  It will show that the reductions can be as much as 0.29 degrees F for the full 30% reduction by 2030, or 0.096 degrees F for the Clean Power Plan of 30% emissions reduction from the power sector.

The new Clean Power Plan’s rules to reduce CO2 from US power production by 30% by 2030 are being highly debated.  The new rules are being denigrated by conservatives using a ubiquitous estimate that they will only reduce global warming by 0.018 degrees C by the end of this century.  The Cato institute provides a calculator and a discussion of the source of that or alternate numbers on its website.

The calculations use a simplified climate model called MAGICC put forth by NCAR, the National Center for Atmospheric Research, and UCAR, the University Corporation for Atmospheric Research.    It is centered around the A1B model of worldwide economic development and mitigation efforts until 2100.  Hopefully, the world will follow something even better than  this development, which although it has growth in yearly greenhouse gas outputs until 2040, it turns over there and outputs sharply reduced by the end of the century.  The concentrations or radiative forcings keep increasing since CO2 lasts on the order of 100 years.  However, you can argue that this heavily mitigated A1B model is not the best starting point for showing the effect of greenhouse gas reduction rules against a business-as-usual background that we are only starting to mitigate.  Here, I will estimate the effect with a business-as-usual model.

The economic climate paths have been superseded by Representative Concentration Pathways (RCP) that just present courses of greenhouse gases or total radiative forcing during this century, without detailed economic and mitigation models.  They are labeled by the ending radiative forcing at year 2100 in Watts per square meter.  They are shown in the figure below.

reductions radiative forcing

Below is shown the CO2 equivalent concentrations including all forcing gases and effects for the four RCPs.

reductions CO2

 

The one closest to A1B is RCP 6.0, with and ending temperature increase  for 2081-2100 above the period 1986-2005, centered around 2.2 degrees C (4.0 F) over preindustrial times, with range from 1.4 to 3.1 degrees C.  (To convert to the period 1850-1900 add 0.61 degree C.)  The trajectory considered more as business as usual is RCP 8.5, which is the highest considered, and which we have already started tracking with our limited mitigation efforts.  This has an ending temperature increase centered around 3.7 degrees C (6.7 degrees F), with a 90% inclusive range from 2.6 to 4.8 degrees C (4.7 to 8.6 F).  I think it is more realistic to measure the effects of rules for GHG reduction from the starting trajectory of no reductions, than from an already highly mitigated trajectory.  Thus I will use the RCP 8.5 trajectory.

The fraction of US GHG emissions in 2012 generated by the Electricity Sector is 32%.  The CPP rules call for a 30% reduction of this by 2030.  That would be a 9.6% reduction in total US emissions.  (Coal results in 24.5% of total US emissions, and 44% of world emissions.)  The US emitted 15% of worldwide emissions in 2012.  Applying the 9.6% reduction to this gives a CPP reduction to worldwide emissions of 1.44%.  Now that seems small in itself.  However, the argument is made, if we, the richest large nation, does not make such an effort, how can we expect any other nations to do likewise.

Now the MAGICC calculations assume that we continue our same percentage emissions among the 90 OECD nations.  Applying this to the world as a whole, even as other countries develop economically, we do also, maintaining the same percentage of emissions before reductions.  Thus, of the final RCP warming trajectory, this will reduce the 2100 temperature increase by 1.44%.  If we look at the RCP 8.5 increase centered around 3.7 degrees C, the Clean Power Plan rules would reduce it by 0.053 degrees C, or 0.096 degrees F.  This is almost a factor of 3 greater than the standardly quoted 0.018 degrees C.  This straightforward way of calculation removes a lot of the hidden modeling assumptions, but shows that different pictures can change such values by a factor of three.

The total US goal is to lower all emissions by 30% over 2005 emissions by 2030.  Since that will now apply to triple the amount of emissions as the Electricity Sector alone, it could reduce century ending temperature by almost 0.16 degrees C, or 0.29 degrees F.  Applying the 90% range from RCP 8.5 the overall US 30% reduction gives a range of 0.11 to 0.21 degrees C (0.20 to 0.38 F).  Seen as part of a whole, the reduction from CPP gains greater significance.

Posted in California Power Mixes, Climate Change, Coal, Electric Power, Energy Efficiency, Fossil Fuel Energy, Greenhouse Gas Emissions, Natural Gas, Politics, Renewable Energy, Solar Energy, Wind Energy | Leave a comment

Projections and Agreements on Climate Change: Talk by David Victor

Dr. David Victor of UCSD gave the Reeburgh Lecture at UC Irvine on December 10, 2014.  It was titled “Getting Serious About International Cooperation on Climate Change”.  This is a listing of some of his main points. The talk will be on the UCI Physical Sciences website.

Negotiations on greenhouse gases have not been effective.

Initial Kyoto signers would have covered 59% of greenhouse gas (GHG) emissions. Those that stayed in the accord covered only 23%. The 2011 renewal only covered 13% of emissions.

Continuing as usual will result in 3-4 degrees C of warming by 2100.

We would need 80% reduction in emissions to keep warming to only 2 degrees C above pre-industrial times. This is just not possible.

Analysts love markets such as cap and trade or taxes

Politicians love regulations that hide the costs.

California cap and trade has achieved only18% of desired reductions. Regulations will do the rest.

Agreements must be flexible to allow for national implementation strategies.

Globalization is good for climate policy, since it spreads technology.  For example, the best power plants are used around the world.

It is easy for a country to outsource manufacturing and emissions to achieve its emission goals. Great Britain is an example.

The San Francisco Bay Bridge was built from parts manufactured in Asia.

Climate policy for GHG reduction also reduces black carbon and sulfur dioxide pollution.

The best agreements come from “clubs” of countries. It is easier to make a deal in a smaller group.  For example, the recent US-China agreement.

GHG reduction will be a long, slow process.  Significant warming will still occur. We will be forced to over adapt.

Climate change problems lead to security issues.

Russia may want some warming for a longer growing season.  Saudi Arabia want us to fail in limiting fossil fuels.

Poor societies don’t have money to adapt, while rich societies do. Poor societies will suffer.

 

 

 

 

 

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Politics and the Fossil Fuel Industry versus the Laws of Nature and Economics

The fossil fuel backers and climate deniers now control both house houses of Congress, about two-thirds of state legislators and governors, and state attorney generals. All of these are set to oppose the EPA greenhouse gas pollution regulations and clean energy subsidies. As much as they deny climate warming or man-made sources, they cannot change the natural phenomena of climate change, or its continual growth from man-made sources. The effects get stronger every year, and the scientific case for both climate change and its cause of fossil fuel pollution gets stronger every year.

The flooding of Miami will rise no matter how many deniers they elect as Governor. The rest of the world that has freedom of science will continue to be convinced of the effects and source. The costs will rise and insurance companies will start charging more for necessary protection since they face realistic claims.

Since natural gas is currently cheaper than coal and much cleaner, it will continue to replace the old coal plants even without government regulation, as the laws of economics dictate. Current wind power will continue to generate economic power, although its growth will be slowed without subsidy. However, the environmental damage from coal mining, from coal pollution, from ash pits, and its health costs will continue, and be better documented every year. They will also lead to public protest, no matter which politicians dominate the state.

Solar power gets cheaper every year, and that should continue, with even more efficient solar cells. Renewable and natural gas industries also have their lobbyists to fight for cleaner power. Gas saving cars are still better investments, and will continue to drive down the price of gas since less will be needed. Environmental policies will still make progress in the one-third of states that are not conservative and fossil fuel dominated. Cleaner air and water will results.

While we bemoan the fossil fuel industry takeovers of government sectors, the laws of nature, of scientific investigation, and economics will continue to make sense despite imposed political ignorance.

 

 

 

 

 

 

 

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Updated Lectures on Natural Gas Greenhouse Gas Limits, and Russian Natural Gas

I have updated the Greenhouse Gas version in the previous post to include a figure for how the comparison of methane versus carbon dioxide warming by weight over counts methane molecules by about a factor of three.  Instead of the warming of methane over carbon dioxide being a factor of 34 by weight, it is reduced to a factor of 12 by molecule, which is important in referring to energy production and fugitive methane leakage.

I also include a figure that illustrates the calculation of what the amount of leakage of methane or the breakeven point would be if old 33% efficient coal plants were replaced by 60% efficient combined cycle gas turbine natural gas plants.  The breakeven point would be 20% leakage of fugitive methane compared to methane used for power production.  This is compared to the previous breakeven of 3% calculated using the incorrect comparison by weight, and replacing 33% efficient coal plants only by 33% efficient natural gas plants.

Natural Gas Lecture Update

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Lecture on US and Russian Natural Gas and World Impacts

This is the part of my Osher Lifelong Learning Institute (OLLI) lecture on US and Russian Natural Gas and their World Impacts.  It contains impacts on Europe, Ukraine, Russia, and China and Middle East reserves as well.  I want to thank Peggy Maradudin for teaching her OLLI classes on Russia, where much of this knowledge was gained.

US and Russian Natural Gas and World Impacts

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Lecture on Natural Gas and Greenhouse Gases

This is my Osher Lifelong Institute Lecture on High Efficiency Natural Gas Plants as a replacement for old, low efficiency coal plants, and its dramatic effects on lowering greenhouse gases for energy production.

Natural Gas and Greenhouse Gases

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Comparison of a Honda Civic Natural Gas Car with a Gasoline Honda Civic, and two Electric Hybrid Cars

 

We compare the price, fuel economy, cost and mileage range of a Honda Civic Natural Gas car with a gasoline Honda Civic, a Honda Civic Hybrid, and the Toyota Prius Hybrid. The table is formed from www.fueleconomy.gov, from the Department of Energy.

Comparison of  Natural Gas cars

First, in price, the Honda Civic Natural Gas starts at $8,450 more than the Honda Civic gasoline, which is 46% more. Of course, it may come with a lot more than standard equipment, since the high end listing is only $4,800 more. The Honda Civic Hybrid is $6,445 more than the gasoline basic one, but only $2,845 more at the high end. The Toyota Prius Hybrid is $6,010 more than the Honda Civic gas at the low end, and $5,515 more at the high end.

The fuel economy comparison that I would like would be in Greenhouse Gas Pollution per year per vehicle. CARB, California Air Resources Board states that on a lifecycle analysis, Natural Gas vehicles will produce 28% less CO2 equivalent greenhouse gases. Natural Gas also almost eliminates the nitrogen oxides that causes smog, the volatile organic compounds, carbon monoxide, and sulfur dioxides. The key users of natural gas vehicles are Pakistan and large cities in India.

Here, I will use the annual cost for 15,000 miles driven given in the table we are analyzing. I of course like to point out that you can cut the fuel cost in half, a third, or a fourth by carpooling.

For the Honda Civic gasoline, it cost $1,400 to drive 15,000 miles in a year. If after five years its fuel savings over an average car is $3,000, the average car must spend $600 more per year, or a total of $2,000 per year.

The Honda Civic Natural Gas has a yearly fuel cost of $1,050 compared to the Honda Civic gasoline at $1,400, or savings of $350 a year. The natural question is how many years does it take to break even over the $8,450 basic price? The answer is 24 years (gulp). For the high end vehicles, the $4,800 difference takes almost 14 years.

Now we compare the Honda Civic Hybrid car with the gasoline Honda Civic and the Honda Civic Natural Gas. The Honda Civic Hybrid costs $6,445 over the Honda Civic gas, yet is $2,005 less than the Honda Civic Natural Gas. The Hybrid uses 2.2 gallons of gas per 100 miles, while the gasoline Civic uses 3.0 gallons per 100 miles. Taking the ratio 2.2/3.0 = 0.73, so the Hybrid saves 27% of pollution of all types over the gasoline Civic. That is almost the same as the 28% CO2 pollution savings of the Natural Gas model over the gasoline version. Of course the greater Hybrid advantages are that you do not have to search out a natural gas station, and get 600 miles per tankful, rather than less than 200 miles in the Natural Gas version.

Still comparing the fuel cost savings of the Hybrid Civic over the gas model, is a savings of $2,000 over five years, or $400 a year. To break even with the $6,445 price difference will take 16 years. The price difference of the top end of the Hybrid over the gas model is $2,845. It would take 7 years to break even on that.

Finally, we compare with the popular Toyota Prius Hybrid. Its base cost is about the same as the Honda Civic Hybrid. Its savings over the Honda Civic gas is $500 a year. It uses only 2.0 gallons per hundred miles instead of 3.0, which is a savings of 33% of all type of pollution over the gas model. It is always surprising that if you increase from 33 mpg to 50 mpg, an increase of 52% in mpg, since the pollution is proportional to the inverse of mpg, or gallons per mile or hundred mile, that the pollution is reduced by the smaller number 33%.

The price of the Toyota Prius is $6,010 more than the gasoline basic Honda Civic. At a gas cost savings of $500 a year, it would pay for the increase in 12 years. The Prius also has a 600 mile gas tank range, like the Honda Civic Hybrid.

Of course, people buy the lower pollution vehicles to help the environment, which is commendable, not just for the savings in gasoline.

Posted in Autos, Conservation, Energy Efficiency, Fossil Fuel Energy, Greenhouse Gas Emissions, Natural Gas, Osher Lifelong Learning Institutes, Transportation | Leave a comment

Why Keep Including India When Comparing US with China Greenhouse Gas Emissions?

When industry and conservative writers or commentators oppose lowering US greenhouse gas (GHG) emissions, they always point out that China’s are now higher than US emissions, and they are supposedly doing nothing about it, and throw in India as third.  They imply that India’s GHG emissions must be somehow be comparable to China’s or the US’s.  Data really throws ice cold water on that characterization of India’s GHG emissions.

The worlds GHG emissions total 32.7 trillion metric tons as of 2012 in EIA data.  In those units, China’s are 8.55, or 26.1%.  The US has 5.27, or 16.1%.  India, at third, has 1.83 or 5.6%.  The industry commentators say if the US is only 16%, we should just do nothing since it is so small an amount, and China’s are larger.  But they also throw in India, which is only 40% of the US’s, and 21% of China’s.  Of course, in the future India may be able to industrialize and raise their standard of living, and will grow larger in GHG emissions, but that is not the case now.

We also note in comparison by countries, that India is only slightly larger than Russia at 1.78 versus India’s 1.83, or Russia’s 5.44% versus India’s 5.60%.

Another way that India looks small is in comparing regions of the world.  Europe emits 4.26 of GHG, or 13.0% of the world.  That is close to the US emissions, and 2.3 times that of India’s.

Finally, we compare countries and Europe by emissions per capita.  Among large countries, the US is the clear leader (cheers) at 14.1 metric tons per capita, PER YEAR.  (Aren’t we glad that CO2 is a gas, and not an ash mountain that we have to haul away every month.)  The world average is 4.63 metric tons per capita.  Russia is next at 12.0, and Japan at 9.42.  Next is the Middle East at 9.02, and Europe at 7.12, about half of the US.  China comes in at 6.05.  Last comes Africa at 1.11, but a close runner up to last is India at 1.47.  So the US per capita emissions is 9.6 times the per capita emissions of people in India.  That is, a person in the US has a share of ten people in India.  This has never been pointed out by industry or conservative commentators.  The per capita GHG for India is even only a third or 32% of the world average.

Since most energy related CO2 produced is still in the atmosphere warming the earth, we can look at the sum produced by each country or region.  A lot of the emissions was produced in constructing the infrastructure and wealth that the leading countries enjoy.  Of course, since China has only recently become a major producer, the US still leads in the total CO2 produced, at 26%.  China is second as a country at 10.7%, only 41% of the US achievement.  India at 3.0%, is next to last on this picture graph, only exceeding Africa at 2.6%.  India’s total emissions are only 12% of the US’s.

Percentage_share_of_global_cumulative_energy-related_carbon_dioxide_emissions_between_1751_and_2012_across_different_regions.svg

Continually throwing in India with the US and China as comparable in emissions is sorely misleading.  Leaving out Europe and Russia is also really not backed up by the data.

Expecting and watching China’s GHG lowering programs is very interesting, but apparently not followed by conservative commentators.  China has programs in closing old coal plants, planning tens of nuclear plants, building and planning hydro power, leading in solar power production and usage, and importing natural gas.

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Comparison of Greenhouse Warming for Leaked Methane versus CO2 from Coal

 

There are two popular comparisons of greenhouse gas effects of leaked methane versus CO2 from burning fossil fuel.  They involve 20 or 100 year periods, and comparison of the gasses for the same weight.

Neither time period has a basis in actual warming and lifetimes of the gases.  Even worse, the number of greenhouse molecules produced is not directly equal to the actual weight of the gases.  The real comparison should be on the basis of the lifetime of CO2 in the atmosphere, which is several hundred years, not a hundred.  It should also be on the basis of the ratio of energy generated by each source, and the number of molecules produced in burning or as leaked “fugitive” gas.  Then this should be compared by the relative generation of energy per molecule of methane versus carbon atom in coal.  Then we can figure out what percent of leakage of methane with new efficient methane plants would match the greenhouse warming of just using coal in present old plants.  Keeping methane leakage to a small fraction of the limit would lead to only 28% greenhouse gas effect per unit energy than the coal pollution it would replace, as shown in the previous post in this blog.

On a hundred year basis, including effects of aerosols, for the same gas weights, methane is said to be 34 times as warming as CO2.  The hundred year period was arbitrarily chosen for long lived CO2, but its true lifetime is several hundred years and unknown.  We will call its actual lifetime a constant “tc” times 100 years (see footnote).

Methane, CH4, has a lifetime of 12 years in the atmosphere, where Oxygen or OH radicals convert it to a molecule of CO2 and water.  Its short lifetime has already been factored into its comparison with CO2 by unit weight, on the hundred year basis, to give the factor of 34.  Despite the short lifetime, it takes around 60 years for the pulse of CH4 to reduce enough to match the greenhouse gas effect of an equivalent number of CO2 molecules.

We now convert the ratio for both CH4 and CO2 per carbon atom from the ratio per weight.  A molecule of CO2 has an atomic weight C:12 + O:16 + O:16 = 44.  So CO2 has one carbon atom per 44 units of weight:  1C/44 wt.  A molecule of CH4 has an atomic weight C:12 + 4xH:1 = 16.  So CH4 has one carbon atom per 16 units of weight:  1C/16 wt.

Converting the greenhouse ratio by weight of (34 / wt CH4) / (1 / wt CO2) by multiplying (16 wt CH4 / C) / (44 wt CO2 / C) = 34 x 16 / 44 = 544 / 44 = 12.36.  Thus the greenhouse ratio per contained C atom is about 12.4.

With “tc” being the number of centuries for CO2 to be disposed of, the greenhouse ratio per contained C atom is about

R = 12.4 / tc.

The approximation of just dividing by tc is only approximate, for small tc. For example, for a 500 year CO2 lifetime (tc = 5), the initial greenhouse gas factor of CH4 to CO2 is reduced from 25 to 7.6, or by the factor 0.30, not 0.20, as the simple formula would indicate. The formula would be correct for the excess warming by the initial CH4 pulse, before the C in it got converted to CO2.

The question we now have is what amount of leakage of methane will just balance the savings of CO2 pollution from replacement of coal plants by natural gas plants.  This depends on the relative efficiencies of the two types of plants, and the fact that one CH4 molecule burns to about the same energy as two carbon atoms, and therefore makes half the CO2, if their respective plants had the same efficiency.

In the previous post we showed that replacing an old coal plant at 33% efficiency with a new combined cycle natural gas plant at 60% efficiency, reduced CO2 down to 28%, rather than just 50%.  So for each 100 coal atoms we burn, we only have to burn 28 CH4 atoms, each of which makes a CO2 molecule.  Another way to say this, is that if there is not CH4 leakage, greenhouse gas pollution can be reduced by 72% by replacing old coal plants with new combined cycle natural gas plants.

We then ask how many fugitive CH4 atoms can we tolerate to restore us back to the same effective greenhouse gas emissions as the 100 coal atoms.  The difference is 100 – 28 = 72 CO2 molecules missing from the CH4 burning.  But each fugitive CH4 molecule is equivalent to 12.4/tc CO2 atoms in greenhouse strength.  So we divide the 72 CO2 molecules by 12.4/tc = 5.8 * tc molecules.  The fraction of fugitive methane to the 28 burned methane molecules at break-even is then

Feven = 5.8 * tc /  28 = 0.21 * tc.

So we can tolerate 21% x tc leakage and still break even in our replacement of an old coal plant with a new combined cycle natural gas plant.  This is far greater than the 4% or 3% leakage break-even fraction calculated with the old naive pollution ratio of 25 or 34 in the useless units.

As an example, if leakage is 10% and tc is 2 for 200 years CO2 retention, the fraction of Feven is

f = 0.10 / (0.21 * 2) = 0.10 / 0.42 = 0.24,

or 24% of the break-even is leaked away.  So the greenhouse savings of 72 CO2 molecules has to be reduced by 24% to 55 molecules, meaning there is a savings of 55% greenhouse gases over just the old coal burning plant.  So instead of 3% or 4% leakage being the old break-even point, even 10% leakage now could give us the near 50% savings as with no leakage in the old, incorrect calculation.  No leakage in the new calculation gives us 72% savings in greenhouse gases.

We give a table of greenhouse gas emission reductions for CO2 lifetimes of 100 years and 200 years, and leakage rates of 0%, 3%, 5%, and 10%.

Greenhouse Gas Emission Reductions Converting Old Coal to New Natural Gas Plants:

CH4 Leakage - 0%                   3% 5% 10%
CO2 100 years lifetime 72% 62% 55% 38%
CO2 200 years lifetime 72% 67% 60% 55%

 

Richard Muller, of UC Berkeley, in “Fugitive Methane and Greenhouse Warming” has a similar argument, and comes up with a 14% fugitive cap, below which warming is reduced for the same energy produced.  He only considers the 100 year CO2 period, but also includes the added efficiency of new combined cycle natural gas plants at 60%, versus new efficient coal plants at 43%.  He also has general formulas for calculating the cap including plant efficiency and general greenhouse gas ratios.

 

Footnote:  The CO2 is actually absorbed by carbon incorporated into phytoplankton grown in the top ocean layer that then falls to be sequestered at the bottom of the ocean.  Since growing ocean acidity is already making the growth of oyster shells difficult, increasing acidity will cause less plankton to form and increase the lifetime of CO2.  This is a positive feedback to the amount of greenhouse gases.  It also makes the lifetime of CO2 releases today actually unknown, and dependent on how much we slow greenhouse gas production.

 

 

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Replacing Old Coal with New Natural Gas Plants Can Reduce CO2 Production to Less Than a Third Per Plant

It is well known that since natural gas generates half the CO2 for the same energy produced as coal in current plants, that replacing old coal plants would reduce CO2 pollution by a half for the switched plants.  Those calculations assumed the present efficiency of energy generation of both coal and natural gas plants at the same 33% as at present, for steam generating plants.

However, reading an article by Richard Muller, “Fugitive Methane and Greenhouse Gases” , has made me aware that new combined cycling natural gas plants can be up to 60% efficient.  We redo that method comparing CO2 from replacing an old 33% efficient coal plant with a 60% efficient natural gas plant.  A combined cycle gas turbine (CCGT) plant first burns natural gas to drive a turbine, and then left over heat is sent to a steam generator to add roughly 50% more output to the plant, over the gas turbine.

CO2 is proportional to fuel usage per molecule or atom, since coal is mostly burning carbon atoms C, and natural gas or methane, CH4, also contains only one carbon atom.  The extra Hydrogens in CH4 oxidize with Oxygen to form water, but generate about the same amount of energy as oxidizing the Carbon atom in CH4 to CO2.  Thus the factor of twice the energy from burning a methane molecule than a coal atom.

Taking a coal or carbon atom at 33% efficiency, means that you need 1 x 1/.33 = 3 carbon atoms to burn to generate the amount of electricity contained in burning the atom itself.  For a natural gas molecule, you need only one half a molecule to get the same starting energy, but then for 60% efficiency, you need a factor of 1/0.60 more, giving the comparable fuel usage of 0.5 x 1/0.60 = 0.83 molecule.  The ratio of CH4 to C fuel usage is then 0.83 / 3 = 0.28.  That is also the ratio of CO2 pollution, since one C atom comes from each.

So instead of the ratio of CO2 from methane over coal being a half for present plants, the ratio is actually between a third and a quarter for a new combined cycle natural gas plant and an old coal plant.

 

 

 

 

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