Tuesday, April 12, 2011

Gas Is Cleaner Than Coal: What Cornell Prof Gets Right and Wrong

"In other ways, I'd say coal is worse, without question," said Professor Howarth of Cornell University in today's The Patriot-News at page 4 about all pollutants other than carbon or heat trapping gas.

More on the important issue of heat trapping pollution that has already raised global temperatures and Professor Howarth's study in a moment.

But let's thank first Professor Howarth for making it clear that he agrees that gas is cleaner than coal on mercury, arsenic, lead, soot, nox, sox and a host of pollutants that sicken hundreds of thousands and cause up to 36,000 premature deaths each year, according to the Environmental Protection Agency, just from smog forming pollutants.

Coal burning power plants account for 90% of the toxic pollution coming from all power plants in the United States.  Just focus on mercury.  Gas emits no mercury.  But mercury powers out of old coal plants with next to no pollution controls. So much mercury from coal burning has been put in the atmosphere that fish are contaminated (See the blog posting about the 2011 Pennsylvania Fish Consumption advisory) and then people eat the fish.

As a result, one out of 6 women has elevated levels of mercury so that any babies they may have could suffer from reduced IQ. 

So again thank you to Professor Horwath for not disputing the overwhelming scientific case that gas is much cleaner than coal on pollutants other than heat trapping gas.

Nobody disagrees that gas when combusted releases about 50% less carbon than coal.  But Professor Horwath says that when you do a "life cycle" analysis of coal and gas, then you find that gas emits more heat trapping gas than coal.

Consumer beware!  The author of any life cycle analysis can get to a result quite easily, because life cycle analysis swings greatly on the assumptions, data inclusions, and data exclusions.  It is not a simple scientific measurement.

To take just one example among legions, Professor Horwath himself is quoted to say in The Patriot News today that he assumed methane emissions during the initial flowback period of a well are never flared but vented fully into the atmosphere.  In fact anyone who spends anytime in the Marcellus knows that not to be true because the flares are quite visible. 

Horwath said to The Patriot News that if the wells are flared the results of the study change.  "It's very difficult to figure out how often they do that rather than simply let it vent.  The data is far from perfect."  But Professor Horwath just adopted an extreme and false assumption of no flaring that conveniently moved the result of his life cycle analysis in the direction that he wanted. 

And Professor Horwath does want the result to which he gets.  He is a committed opponent of gas drilling and fracking, a position to which he is entitled in this free country.

What else has Professor Horwath said about the data that he uses in his study?  On March 15, 2011 he is quoted as calling the data used in his study as "lousy", "really low quality," "teased apart out of PowerPoint presentations here and there."  In a court of law, those would be case determining admissions.  In a boxing match, the ref would stop the match.  In science, they are an expressway to junk.

Especially troubling to me, Professor Horwath also rejects major conclusions from the Intergovernmental Panel on Climate Change that would lead to a big bronx cheer were polluters to do the same in service of their life cycle analysis.

Professor Horwath's conclusion that gas emits more heat trapping gas than carbon flies in the face of numerous life cycle studies done around the world.  And more studies from credible organizations with strong environmental credentials are in the works.

But to take just one, in July 2010, the National Energy Technology Lab (http://www.netl.doe.gov/) that has no ax to grind published a presentation of its life cycle analysis of coal and gas.  See http://www.netl.doe.gov/energy-analyses/refshelf/PubDetails.aspx?Action=View&PubId=315

What did NETL, a government energy lab, find? That coal emitted about 50% more carbon on a life cycle basis.  Did the NYT or the media go into feeding frenzy mode when NETL came forward with its analysis? 

Just seeing if you are awake.


  1. I commented on this study this morning in The Metro: http://bit.ly/gZzZ13
    Your points on mercury and all the other nasty stuff is totally valid,
    but in the public square these issues are discussed with cudgels, not scalpels. The idea that Gas is better on a climate change perspective is pretty questionable and it's worth serious questioning. And if it's not better, why are we bending over backwards to give it the green light?

    I stand by what I said to The Metro: if the industry would let Howarth come in and really study its sites, pipelines, compressors and etc, that could be pretty informative, but they won't, because he's right.

    At least, that's what my gut tells me after watching a lot of infrared videos like this one:

  2. Brady:

    I received email notice of your comment but it is not at the blog. I of course would like to publish it and discuss it as well. Would you resend?

  3. John, sure. I will probably be more succinct this time.

    You are 100% right about all the other pollution that comes from coal and oil. I just think what Cornell has done here is important because in the public mind Natural Gas is benign, from a climate change perspective. I think it's really important to counter that, because I don't buy it.

    I was quoted on this topic in THE METRO this morning, daring the industry to let the scientists come onto well pads, compressor stations and go along pipelines and try to collect really good data. I bet we'd find it is even worse than the estimates.

    It's true, Howarth admits to using poor data, but he also makes a convincing case that his estimates are conservative anyway. More study is needed, and I bet the industry will fight more study taking place.

    I believe Howarth is right from a climate change perspective. All those infrared videos of compressor stations come to mind and are, to my mind, very compelling.

    It's true, Howarth is doing cudgel PR here, not laser PR. But cudgel PR is kind of how it works. Sad but true.

  4. Never mind arguing about whether natural gas is cleaner than coal when burned. What about the costs of its extraction? What about hydraulic fracturing? What about methane release? What about ground water pollution? What about stuffing toxins into the ground with who knows what future result? As Secretary of the Pennsylvania Department of Environmental Protection Mr. Hanger didn't do a very good job of protecting the environment of the residents of Dimock Pennsylvania!

  5. Ed:

    Burning coal and oil at power plants kills over 17,000 people per year just from the toxic pollution released. Gas does not do that. Both are facts. See the EPA data.

    Now you are correct that gas extraction has impacts and gas drilling and production most certainly is industrial activity. It must be heavily regulated: rules must be strong; enforcement staff must be sufficient; political leaders must tell the enforcement staff to enforce the rules; and the industry itself must develop a true culture of safety.

    I became Secretary in September 2008 and enacted 4 new, strenghtening policy/rule packages (water withdrawal, water disposal, well drilling standards, 150 feet buffers for HQ streams); increased the enforcement staff from 88 to 202 (hiring in 2009 plus twice in 2010); opened 2 new offices to put enforcement staff near new areas of drilling; staff issued 1400 violations from january 1, 2008 to june 30, 2010 and did not have to get my permission to issue a violation; we made the drilling company in Dimock plug 3 gas wells costing millions to it and landowners; repair other gas wells; stopped drilling and fracking for more a year; cleaned 14 of 19 water wells by December 2010 that had been contaminated with gas; and had the drilling company pay on average $200,000 to each of the 19 families, including to those who had their water wells cleaned up.

    But the extraction and production damage created by coal mining and oil production are extensive too. In fact both do more damage than gas drilling. Just in Appalachia 500 mountain tops have been blown up and 1200 miles of streams buried to get coal. Just in West Virginia and Kentucky.

    One oil well out of control devastated the Gulf. There are huge plumes of oil in communities around America such as the one in Philadelphia. There are tens of thousands of underground oil storage tanks that are leaking and abandoned. There was a major oil spill on the Delaware river from a tanker just a few years ago.

    It just is not factual to say the damage done to the environment during the extraction process for coal and oil is less damaging than gas.

    We all should use energy carefully because none of it has no impact. We should accelerate alternatives like wind and solar and I led successful efforts to build 16 wind farms in pa, with another 4 under construction now, install more than 3,000 solar facilities, and more.

    But gas creates less impact than coal and oil when it is combusted and when it is produced. California now uses no coal and gets its electricity from gas (55%), nuclear (15%), large hydro (12%), and renewables (18%). California has a much cleaner mix than the national mix of 45% of electricity coming from coal, with gas at 24% and all renewables including large hydro providing 10%.

  6. John,

    You do an enormous service to your state and your country. I know quite a lot about shale gas drilling and production and I also study global warming and am quite concerned about it. To me, shale gas came out of nowhere to give us a chance to reduce GHG emissions and other pollution while we move as quickly as possible toward renewable energy. Reading the articles written about shale gas by ProPublica and the NYT has been one of the more frustrating and disillusioning experiences of my life. It makes me question everything that the NYT writes. If their other reporting is as bad as this then we can't trust a word they write.

    Howarth's comparison only works for electricity generation. If gas is used directly as it is in many industrial and commercial uses, heating, cooking and hot water, it is far more efficient than using coal-fired electricity. Not only does burning coal create more GHGs than gas when burned, there is about a 50% loss during electric transmission so coal-fired electricity might produce four times the GHGs of burning gas directly.

    Howarth's main problem - in fact the main problem with a lot of this reporting - is a lack of understanding of even simple facts about the gas industry and in this case the coal industry. He grossly overestimates the methane emissions from gas drilling and production and grossly underestimates the methane emissions from the coal industry. In fact, there may be more methane emitted from the coal industry than the gas industry per unit of energy produced. Remember that there is enough methane in coal to drill wells for it and the reason so many miners die is from explosions due to high methane levels in the mines.

    You correctly point out that almost all of the methane that comes out of the wells during drilling and completion is flared so it is released as CO2 not methane. Similarly almost all of the gas lost from pipelines is not leaking out of the pipe as methane but removed to run compressors. Again it is being burned so it is released as CO2 not methane. Either Howarth did not know these basic facts due to near complete ignorance of what he is opposing or he is willfully misleading people. In the end more reports like this could lead to thousands more deaths from coal burning as well as a warmer planet down the road.

  7. More important info from Michael Levi of the Council on Foreign Relations:

    Second, Howarth’s gas-to-coal comparisons are all done on a per energy unit basis. That means that he compares the amount of emissions involved in producing a gigajoule of coal with the amount involved in producing a gigajoule of gas. (Don’t worry if you don’t know what a gigajoule is – it doesn’t really matter.) Here’s the thing: modern gas power generation technology is a lot more efficient than modern coal generation, so a gigajoule of gas produces a lot more electricity than a gigajoule of coal. The per kWh comparison is the correct one, but Howarth doesn’t do it. This is an unforgivable methodological flaw; correcting for it strongly tilts Howarth’s calculations back toward gas, even if you accept everything else he says.


  8. Sorry for so many posts, but here is another key fact - 70% of natural gas is used directly by industry and homeowners while 30% of what is produced in the US is used for power generation. Even if we take accept all of Howarth's flawed assumptions, it is far cleaner to use gas directly (for heaters, etc) than to use coal-powered electricity when one factors in the transmission related losses of at least 50% of power generated.

    Here is a reference on that usage: http://www.eia.doe.gov/kids/energy.cfm?page=natural_gas_home-basics

    Another key point is that natural gas power generation is much easier to locate close to where it is used so the transmission losses from natural gas are significantly lower than those for coal power.