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"Coal for Water" Why Moving to Clean Energy in China Can Also Prevent a Water Crisis

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By Tania Ullah

In April, the Chinese government made an announcement that it is stopping the construction of new coal-fired power plants that amount to a whopping 105 GW of electricity generation. While this planned shut-down is likely a response to the slowdown of the Chinese economy, it is also China’s biggest chance for sustainable energy development. In addition to reducing carbon emissions, introducing more clean technology in the energy sector would also provide China with an opportunity to save its precious water resources.

With over 20% of the world’s population, the nation only has seven percent of the water reserves needed to sustain food production, industrial output, and domestic use. Surface water sources are also shrinking. China used to be home to over 4,000 lakes, but about half have disappeared in recent decades due to increased consumption and climate change.i In the arid North China Plain alone, where much of the agricultural land and power plants are located, increased pumping of groundwater is starting to deplete aquifers. Additionally, deserts are expanding, with over one-third of mainland Chinese regions carrying water resources comparable to the desertification seen in the Middle East and North Africa.ii It is abundantly clear that China needs to intervene to save itself from a water crisis.

Flag by the Shaanxi Government Building - Xi'an

What do coal plants have to do with water? A hidden development challenge

China is the largest coal user in the world and nearly 70% of their electricity production comes from the fossil fuel.iii The use of coal receives much attention – as it should – because it makes China the greatest greenhouse gas (GHG) contributor in the world, emitting more than 25% of total global GHG emissions in 2012.iv However, it isn’t just emissions that make them dangerous. Coal-fired power plants have the additional drawback of being a large consumer of freshwater sources, and almost one-fifth of China’s water goes to coal mining, processing, ash control, and cooling in power plants.v What the government is planning to do to curtail water use for energy generation, like phasing out plants that have once-through cooling (i.e. use water once and don’t recycle it) and constructing new plants by shores to use seawater instead, are not enough to address the problem. These cooling methods are less efficient and still require large water withdrawals. Furthermore, the water that is returned to the source after being used is significantly heated and can damage the local ecosystem.

Clean energy as a solution to China’s water problem

The key to addressing the water crisis is for China to shift toward less “thirsty” or water-intensive energy generation. Wind and solar are renewable technologies vital to reducing reliance on water for energy, not only GHG emissions. For every MWh of electricity generated, wind turbines and utility scale solar plants consume almost no water, while almost 250 gallons/MWh are consumed for coal-fired electricity generation.vi To put that into context, approximately 6,000 Olympic-size swimming pools of water are required to power all of the country for a single day using traditional coal-fired plants. China has ambitions for water-reliant power to fall from 94% to 72% by 2050vii, but this goal is unlikely to be achieved without a significant increase in solar and wind capacity.

What is stopping China from taking this opportunity?

China’s hunger for energy power is unlikely to wane anytime soon. The industrial sector is growing at a rapid pace and it has a long way to go to catch up to the United States, which consumes four times the energy per capita of China.viii What is keeping China beholden to coal is the easy credit given to companies to build coal-fired power plants and local governments’ reliance on these plants to create jobs.ix The state’s heavy regulation of the energy market is guaranteeing profits for plants even with falling coal prices. Small domestic incentives exist for renewables, but what Beijing desperately needs to do is create and enforce policies to make more room for wind- and solar-generated electricity on the grid. Such an effort will help the country meet its long-term commitments to save both water and energy resources.

Tania Ullah is a mechanical engineer at the National Institute of Standards and Technology (NIST), conducting research on energy- and water-efficiency of buildings. As her career progresses, she hopes to draw more needed attention to the intersection of water and energy issues. Tania was a CELI Fellow in Spring 2016.

iBrooks, Nina. 2016. “Impending Water Crisis in China”. Blog. The Arlington Institute: World’s Biggest Problems. Accessed May 12. http://www.arlingtoninstitute.org/wbp/global-water-crisis/457

ii Ibid.

iiiShifflett, Susan Chan, Jennifer L Turner, Luan Dong, Ilaria Mazzocco, and Bai Yunwen. 2015. China’s Water-Energy-Food Roadmap: A Global Choke Point Report. Washington, DC: Woodrow Wilson International Center for Scholars. p10. https://www.wilsoncenter.org/sites/default/files/WATER-ENERGY-FOOD%20ROADMAP.pdf

ivLiu, Zhu. 2016. China’s Carbon Emissions Report 2015. Cambridge, MA: Harvard Kennedy School Belfer Center for Science and International Affairs. p1. http://belfercenter.ksg.harvard.edu/files/carbon-emissions-report-2015-final.pdf

v Shifflett, et al., China’s Water-Energy-Food Roadmap: A Global Choke Point Report. p2.

vi Macknick, Jordan, Robin Newmark, Garvin Heath, and KC Hallett. 2011. A Review of Operational Water Consumption and Withdrawal Factors for Electricity Generating Technologies. Golden, CO: National Renewable Energy Laboratory. pp12-13. http://www.nrel.gov/docs/fy11osti/50900.pdf

viiTan, Debra, Feng Hu, Hubert Thieriot, and Dawn McGregor. 2015. Towards a Water & Energy Secure China: Tough Choices Ahead in Power Expansion with Limited Water Resources. Hong Kong: China Water Risk. p27. http://chinawaterrisk.org/wp-content/uploads/2015/04/Towards-A-Water-Energy-Secure-China-CWR0415.pdf

viii Ibid. p4.

ixForsythe, Michael. 2016. “China Curbs Plans for More Coal-Fired Power Plants”. The New York Times. http://www.nytimes.com/2016/04/26/business/energy-environment/china-coal.html

Photo Credit: Will Clayton via Flickr

Content Discussion

Roger Arnold's picture
Roger Arnold on August 10, 2016

If China is canceling construction of 105 GW of coal-fired electrical capacity, that’s very good news — at least for air quality and reduction of carbon emissions. But I don’t buy the argument that it will solve China’s impending water crisis — or even have much effect. Nor do I agree that a massive build-out of wind and solar facilities is any solution. It’s arguably a good idea for other reasons, but its contribution to the water problem would be negligible.

The consumption of water by power plants is a much more complicated issue that what it’s usually presented as being. The only part of the cooling water flow that is actually “consumed” is the part lost to evaporation. And even that just goes into the atmosphere, to fall as precipitation somewhere else.

China has been drawing down aquifers in major regions at a totally unsustainable rate. As I recall, the water table in the Beijing region has been falling at the rate of a meter per year. I don’t know how much water is lost to evaporation from irrigation in arid regions brought under agricultural production. I’m sure there’s some, and it’s probably significant. But just as in many other parts of the world, the major culprit is climate change.

Unfortunately, it’s going to take a hell of a lot more than switching to power sources that don’t draw cooling water to redress that problem.

Nathan Wilson's picture
Nathan Wilson on August 10, 2016

… to curtail water use for energy generation, like phasing out plants that have once-through cooling (i.e. use water once and don’t recycle it) …

The opposite is true: once-through cooling is a water efficient method for cooling thermal plants; this is where water from the sea or river is used once then returned to the source (with a much lower thermal impact than sunlight, except on a very small area). In contrast, the cooling towers (which misguided anti-nuclear groups like Riverkeepers often demand) consume lots of water because they use evaporation to cool the system.

Therefore China’s current strategy of building more coastal (seawater cooled) nuclear plants is a great idea (they have a world-leading build rate of 6 GWatts/year, which provides more energy than 20 GWatts of solar, without increasing the need for “flexible generation” such as from more fossil fuel burning).

Thermal power plants (such as nukes) can also be air cooled like a home air conditioners (called “dry cooling”). This is less efficient and more expensive, particularly with low temperature systems such as geothermal plants. China is also developing pebble bed nuclear reactors, which operate at a much higher temperatures than geothermal plants and even conventional light water reactors; these would minimize the cost penalty for dry cooling.

Also, since agriculture is typically the largest and majority water user in any developed society, efforts to “prevent a water crisis” must start there. In addition to choosing water-efficient farming practices, we should minimize the use of biomass energy, since that always (directly or indirectly) competes with agriculture for land and therefore for water (since water is used to boost agricultural productivity).

Roger Arnold's picture
Roger Arnold on August 10, 2016

I hesitate to say negative things about global climate models, since they’ve taken so much bad press from the AGW denial camp. But one area where they really are weak is in modeling and predicting changes in precipitation patterns. It would be nice if we could say how increased evaporation / transpiration from land use changes in area A would affect precipitation patterns in area B. We’re not there, however, and that makes it difficult to plan effective redial actions for growing water crises.

We do know that some land practices can lead to desertification and the drying out of whole geographical regions. We also know that other practices can, at least to some extent, reverse desertification. But I don’t think the subject is really well understood.

One approach to remediation that I’ve advocated is importing seawater to low lying desert land areas and constructing salt marshes. I see that as a kind of “poor man’s desalination project”. The marsh vegetation would put water vapor into the air and lead to increased precipitation somewhere. Unfortunately, it’s hard to say just where and by how much.

Anyway, I see that sort of program as having a lot more potential for helping with water problems than merely switching to power sources that don’t require water cooling.

Engineer- Poet's picture
Engineer- Poet on August 10, 2016

Not to mention, flooding areas which are currently dry has a direct effect on sea levels.