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Why Business-as-Usual Coal Consumption Could Mean Dramatic Changes


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Business as Usual is Not the Status Quo

There’s a nuance about environmentally-focused forecasting that I think gets lost in interpretation far too often: namely, continuing “business-as-usual” activities will not preserve the status quo. Imagine you’re driving a car through a beautiful park, and you continue at a constant speed: eventually you won’t be in the park any more. A constant rate of change – here, vehicle speed – does not keep you in the same place. So you’ll leave the park, and then, at some point, you will run out of gas. Or drive into the ocean somewhere. Neither one is a good outcome if you want to stay in the park.

Discussions about climate and other environmental futures often refer to a “business-as-usual” scenario (e.g. [1]), one where we as a society just keep on doing what we’re doing. No behavioral or policy changes are made specifically to address a potential problem, and we make no effort to stop – we just continue along at a constant speed. Consuming energy as we have been doing for years will probably result in some major changes to the way we use land, water, air, and people. Particularly for fossil fuels, continuing a business-as-usual rate of consumption is likely to stress prices and the environment as high-quality resources become harder to access [2] and as we increase the cumulative pollution in the system.

The business-as-usual trajectory does not preserve current conditions, so the fact that a fossil-fueled society has allowed for environmentally acceptable outcomes in some situations thus far does not imply that environmentally acceptable outcomes will continue. Just like a car driving through a park at a constant speed will stay in the park for a while before suddenly exiting, a business-as-usual approach to energy and other resource consumption will keep us in an acceptable region for a while, so it can be easy to assume that continuing what we’re doing will be fine – but that doesn’t mean we aren’t about to step outside the bounds of where we want to be. Ensuring we stay in the proverbial park – the world where we have access to a clean-enough environment, a high-enough standard of living, sufficient access to the resources we need at the prices we can afford, and an acceptable amount of hope for the future – requires that we change our pace. We need to change the business-as-usual rate if we are to preserve the business-as-usual location.

Coal, Business as Usual, and How Things Are Changing

To highlight some of the issues with a business-as-usual rate of energy consumption, let’s focus on coal. Coal is abundant and cheap, but becoming less so; coal’s contributions to local health problems and global climate change throw into sharp relief the fact that business-as-usual activities can lead to conditions that are far from business-as-we-know-it. Coal is the backbone fuel of the American (and global) electricity system, providing about half of US electricity. Coal-fired electricity tends to be cheap, not only because coal is cheap but also because coal plants are often older, fully paid-off facilities that are cheap to operate.

A major problem, though, is that coal’s apparent cheapness is counterbalanced by external costs to things like human and ecosystem health. The National Research Council estimates that external costs of coal-fired generation amount to about 3.2 cents per kilowatt hour, which is close to the electricity’s sale price in some places – and is 20 times the external costs of natural gas-fired generation [3]. Notably, newer plants that are required to have more stringent pollution controls are often far more expensive to operate – few new coal-fired power plants are being built in the United States [4]. And stricter legislation that requires existing coal-fired power plants to add more pollution controls can potentially force the internalization of some of coal’s environmental negatives.

Coal’s cheapness means that to be competitive, other fuels generally need to provide electricity at a levelized cost similar to that of coal – one reason for the title of Google’s RE<C (“Renewable Energy Cheaper Than Coal”) initiative [5]. Right now, renewables tend to compete directly with natural gas, which is higher cost but cleaner than coal, because natural gas-fired power plants are better able to turn on and off to accommodate changing renewable generation [6]. This means that even with high renewable energy penetration, maximal environmental benefits will not be seen until pricing, loading order legislation, or other drivers allow cleaner sources of electricity to replace coal.

Coal-based externalities can have serious impacts on local and larger communities, both human and nonhuman. The triad of traditional pollutants, SOx, NOx, and rocks (particulate matter) is joined by heavy metals and climate change emissions like CO2 and methane (from mines) as a problem for the atmosphere. Water contamination during coal mining can be severe and long-lasting, though impacts vary widely by mining region and mine vintage. Water use for cooling at coal-fired power plants evaporates large quantities of water, heating and discharging far more [7]. Coal combustion gives rise to solid wastes that must be somehow disposed, which can lead to disasters like coal ash spills [8].

So what do we do? Coal-based generation is a major part of the electricity system at this point, and it shapes options for the future. Renewable energy sources are often criticized for having higher market prices (if not lifecycle costs) than coal. Likewise, renewable energy sources are often criticized for not playing nicely with the electrical grid. Of course, the current electrical grid was designed for large baseload thermal plants that don’t turn on and off much – often coal plants – so renewables shouldn’t really be blamed for their inability to perform optimally on a system that was designed for coal but not for them. Either way, the coal legacy is what exists, and the renewable energy and climate policy communities should take the time to understand coal. Coal presents opportunities because of its size, and some challenges can be mitigated by careful study of the underlying issues.

Carbon Capture and Storage: A Tricky Energy Issue

Unfortunately, other challenges can blow up on closer inspection. Take coal’s contributions to climate change. If we were able to remove the carbon dioxide from a coal plant’s smokestack and sequester it in a carbon capture and storage (CCS) process, perhaps coal could continue to provide cheap power without the climate concerns. In a breakthrough technology scenario, maybe.

But as it is, I see a number of problems with CCS that I think are insufficiently recognized. Mainly, most discussions of CCS indicate that the process is highly energy intensive. Parasitic loads, or the amount of electricity that is required to run the system instead of being sold to consumers, are often estimated to be between 5 and 30 percent [9]. That parasitic load means that less electricity can be sold per unit of coal burned. And here’s the real problem – that 5 to 30 percent parasitic load is electrical, and most coal-fired power plants generate electricity from coal at an average 35 percent efficiency [10].

Add in some other auxiliary systems to clean up the flue gas sufficiently to avoid damaging your CCS system, and my research suggests that a coal plant with an amine-based CCS system could require about 80% more coal than a coal plant without CCS, given literature estimates for the parasitic load of a CCS system in 2030 [11], [12]. That’s a lot of coal, and it’s a lot of land, water, air, and social impacts upstream of the power plant. Coal plants pollute, no doubt – but so does coal mining.

Do We Have Enough Coal?

There are two huge questions associated with this possible increased coal demand, to my mind. First, is reducing carbon dioxide emissions from coal-fired power plants worth almost doubling the air, land, water, and social impacts of coal mining – especially when other carbon mitigation options might decrease the demand for coal mining? CCS might be able to reduce carbon emissions to the atmosphere, but the water, land use, and ecosystem impacts of deploying CCS are potentially large. The environment is a complex system, and I think environmental assessments need to acknowledge and address the interplay among systems to be effective. Many choices – like CCS deployment – are discussed in terms of their effects on one system in particular, without mention of predictable associated side effects in other environmental systems.

The second major question is frankly, do we have enough coal to support a near-doubling of demand, especially if projected demand is expected to increase as populations grow? In the United States, the answer to that question is almost alarmingly unclear. We probably don’t have the 250 years’ worth of coal reserves that people often reference [13], at least if we’re actually talking about reserves. A lump of coal is not really a reserve unless it’s legally, economically, and geologically available [14]. Maybe there’s a giant coal seam under a city, or maybe there’s a coal seam that is so contaminated that power plants would not be allowed to burn the coal. That coal shouldn’t count.

More recent estimates of economically available reserves suggest that the US probably has closer to 100 years’ worth of coal [13]. Now halve that to account for CCS and demand growth. Now think about the lifetime of a power plant [9]. Now think about how we might want to invest in environmentally protective energy technologies that can be improved and adjusted for generations of projects. Of course, it’s possible that a disruptive CCS technology could emerge that would dramatically reduce the amount of energy required for the process – and though upstream environmental issues at coal mines shouldn’t be ignored, that would definitely be a welcome advance. But right now, I think it’s a mistake to think of CCS as a truly long-term solution before further study.

Continuing business-as-usual rates of change does not preserve the status quo forever. When considering energy, we should also consider how we want to handle the many and disparate effects that our energy choices have on our environment and well-being. For coal in particular, issues like costs and overall environmental impacts are unlikely to remain acceptable for much longer in a business-as-usual consumption scenario, and thinking bigger, further out, and across as many systems as we can handle is likely a wise choice if we are to preserve what we like about the status quo.

References

[1] US Environmental Protection Agency. “Future Atmosphere Changes in Greenhouse Gas and Aerosol Concentrations.” 14 Apr 2011.

[2] King, Carey W. “Energy intensity ratios as net energy measures of United States energy production and expenditures.” Environmental Research Letters 5.4 (2010): IOP Science. stacks.iop.org/ERL/5/044006.

[3] National Research Council. Hidden Costs of Energy: Unpriced Consequences of Energy Production and Use. Washington DC: National Academy Press, 2010.

[4] Brune, Michael and Michael Bloomberg. “Why America has to get off coal.” CNN: 29 Jul 2011.

[5] Google.org. “Plug into a Greener Grid: RE

[6] Flavin, Chris and Saya Kitasei. “How Renewable Energy and Natural Gas Can Work Together” Worldwatch Institute ReVolt Blog. 22 Dec 2010.

[7] Grubert, Emily. Lifecycle Impacts on Water Resources of Using Coal for Electricity. Proceedings of the 2011 World Environmental & Water Resources Congress, May 22-26, 2011, Palm Springs, CA. doi:10.1061/41173(414)344

[8] Gottlieb, Barbara, Steven G Gilbert, and Lisa Gollin Evans. Coal Ash: The Toxic Threat to Our Health and Environment. September 2010.

[9] Bellman, David. Electric Generation Efficiency. 2007. National Petroleum Council, Global Oil & Gas Study Topic Paper 4.

[10] National Energy Technology Laboratory. “Ultrasupercritical.” Advanced Research: High Performance Materials. Accessed February 5, 2011.

[11] Grubert, Emily. “Mining-related Environmental Impacts of Carbon Mitigation Coal-based Carbon Capture and Sequestration and Wind-enabling Transmission Expansion.” Proc. of the World Energy Congress, Sep 2010, Montreal. Note that the value for additional coal need as presented here is higher when the additional CO2 generated by the coal used to power the capture system is not counted as “captured”; note also that more than 1 unit of electricity is produced per unit of carbon captured.

[12] Grubert, Emily. “Increased Coal Mining Needed to Support Carbon Capture from Coal-fired Power Plants.” The University of Texas at Austin.

[13] National Research Council, Coal: Research and Development to Support National Energy Policy (Washington, DC: National Academies Press, 2007),

[14] Grubert, Emily. Reserves Reporting in the United States Coal Industry and Implications for American Coal Supply. January 2011. USAEE Working Paper Series. Social Science Research Network.

For more references on US coal reserves, see e.g.

[a] Rutledge, David. “Estimating Long-­Term World Coal Production with Logit and Probit Transforms.” International Journal of Coal Geology 85 (2011): 23-33.

[b] United States Geological Survey. “National Coal Resource Assessment.” Energy Resources Program. US Department of the Interior. Last modified October 14, 2009.

[c] Höök, Mikael, and Kjell Aleklett. “Historical trends in American coal production and a possible future outlook.” International Journal of Coal Geology 78 (Mar. 2009): 201-216.

[d] Patzek, Tadeusz, and Gregory Croft. “A global coal production forecast with multi-Hubbert cycle analysis.” Energy 35, no. 8 (August 2010): 3109-3122. doi:10.1016/‌j.energy.2010.02.009.

Images: Emily Grubert

Emily Grubert About the Author: Emily Grubert graduated with Master’s degrees in Energy and Environmental Engineering from The University of Texas in Austin in 2010 and 2011. Emily studies how water and energy systems interact, particularly at points of energy extraction. In particular, she is interested in water used for coal and natural gas extraction and for biofuels production.

The views expressed are those of the author and are not necessarily those of Scientific American.






Comments 6 Comments

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  1. 1. da bahstid 9:15 am 08/23/2011

    Good article. It speaks to just how difficult a conundrum CO2 really presents. It’s not the same as with the ozone layer when all we had to do was switch from chlorofluorocarbons to hydrofluorocarbons. When you burn, CO2 (and water) is where everything thermodynamically wants to go. Anything else costs a lot of energy.

    I don’t see carbon sequestration as being the answer either, not by itself. Maybe we get to a point where we are compelled to reverse raised CO2 by some active means in combination with biofuels. I have a hard time seeing something like that being anything less than several decades away. Speaking very speculatively of course.

    Link to this
  2. 2. huler 11:56 am 08/23/2011

    Excellent piece. Another strong point about “business as usual” not keeping things as they are is that we’re in an accelerating model, not a steady-state model: we use more and more (there are more and more of us), and as the “externalities” of our use build up their consequences don’t continue — they continue to grow. To expand on your car-in-the-park image, try figuring that you’re driving the car up a gentle grade. At some point you crest the hill; if you leave your foot on the accelerator — “business as usual” not only do you speed up because you’re going downhill, you speed up because you’re giving the car gas as it goes.

    Great piece; thanks.

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  3. 3. geojellyroll 7:23 pm 08/23/2011

    More non-science using non-science analogy. Driving through a park, blah, blah…

    Meanwhile back in the REAL world this is not about the ‘USA’…it is about the world. Canadian, Australian, Russian coal supplies are barely scratched. There is no shortage of coal. Coal is and will continue to be the major fuel of energy growth into the forseable future.

    A dollar spent on cleaner coal technology or a more efficient burning internal combustion engine does more for environmental integrity than a hundred bucks flushed down the toilet on more trendy ‘feel-good’ alternatives.

    China will double coal use in the next 20 years…India will double use in just 15 years. The fossil fuel industry is and will continue to be on the cutting edge of of technology.

    At the center of civilization a hundred years ago were coal, oil, wheat and rice. Today it is coal, oil, wheat and rice and a hundred years from now it will be coal, oil, wheat and rice.

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  4. 4. da bahstid 9:06 pm 08/23/2011

    Not to put too fine a point on it but this lass is published and she’s only barely graduated. What have you done recently?

    You accuse the author of being a nonscientist for using analogies for the purposes of making the information accessible to laypeople. And predictably your arguments contain no science whatsoever. Lots of credibility there.

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  5. 5. geojellyroll 11:33 pm 08/23/2011

    Da bahstid.

    Unlike yourself I don’t defer to another American who can’t get their myopic view outside of their borders.

    Hint: The environment is not restrained by borders. The USA is not the world. What happens within the USA is less relevent with each passing year.

    Link to this
  6. 6. da bahstid 12:26 am 08/24/2011

    You must think that is uncommon knowledge and that you are therefore special for being aware of it.

    Link to this

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