The promise of ‘clean coal’

block

PR Shukla and Dr Bert Metz :
In less than two weeks, 193 countries will meet in Paris to agree a new global pact for climate action. This agreement is bound to set the world up for transformational changes, also in our energy system.
Sensing this wind of change, the coal industry is eager to burnish its image of the world’s most polluting fossil fuel.
Today (17 November), leading figures of the coal industry will meet in Brussels to discuss pathways to what they describe as a ‘clean’, low emissions use of coal.
The industry knows there is a problem with carbon emissions and claims that they have found the answer: to upgrade the efficiency of coal-fired power plants and thus make the energy source cleaner.
The industry’s aim is to shore up a place for coal in a global energy mix that considers climate risk, to protect mining companies from competition with cleaner energy technologies, and to rescue utilities from the reputation harm of supplying the dirtiest form of electricity.
It is a natural response for a sector that is coming under growing pressures. Economic slowdown and a growing focus on air pollution in key energy markets such as China has dented global coal demand and prices. In capital markets, a new divestment movement has labelled coal a high-carbon threat to the climate, and convinced university endowments and institutional investors including Norway’s $900 billion sovereign wealth fund to withdraw their investments.
The industry response is to target efficiency. The World Coal Association says that it wants to upgrade the average coal plant in operation today, which converts about 33 percent of the energy content of coal into electricity, to much hotter-burning, “supercritical” or even “ultra-supercritical” plants, with 40 or 43% efficiency.
The idea is to burn less coal in the process, and so emit less carbon dioxide (CO2) and other pollutants per unit of power generation. But does boosting power plant efficiency make coal a “clean technology”? Sadly, the numbers do not add up.
Even the most efficient coal-fired power plants emit more than 15 times the amount of CO2 per unit of electricity compared to renewable energy systems. At more than 750 grams of CO2 per kilowatt hour they also emit more than twice the amount efficient gas fired plants do.
It is globally recognised that to avoid dangerous climate change, i.e. limiting global mean temperature increases to below 2 degrees C, the world can collectively emit no more than about 1000 gigatonnes of CO2 from now on. And that includes all emissions from deforestation, cement production and gas, oil and coal burning. To meet this target, and to have sufficient time to reduce emissions, global annual CO2 emissions must be zero somewhere between 2060 and 2075, and negative thereafter.
Existing coal-fired power plants will already use up a significant part of the remaining CO2 budget during their lifetime. The current pipeline of some 450 gigawatts worth of new coal power projects, permitted or under construction around the world, will add to that. Any new coal plant, irrespective of its efficiency, is clearly incompatible with remaining within the 2 degrees C budget.
From a scientific perspective, there are only three ways to square a safer climate with any new coal-fired power plants.
One option would be to retire the majority of the less efficient coal-fired power plants well before the end of their economic lifetime and only allow for a few new ones with the most efficient technologies available to run for a limited period.
Such a strategy however is both risky and costly. There is a strong resistance from electric utilities to early plant closures, and with the long lifetime of coal-fired power plants, it carries a significant risk of high carbon lock-in and overshooting the below 2 degrees obligation.
A second path to “clean coal” would be to fit every new coal-fired power plant with CO2 capture and storage (CCS) technology.
In theory, CCS technology eliminates 90% of emissions from burning coal, by trapping the CO2 that power plants emit, and burying the greenhouse gases underground. In practice however, the costs of adding CCS are still prohibitive.
The absence of a significant price on CO2, the lack of substantial cost cutting despite the $24 billion in public funding commitments over the past 14 years, slow roll out and the public resistance against CCS also puts a firm question mark over its overall feasibility.
The European Union in 2007 committed to build up to 12 commercial-scale CCS power plants by 2015, but has constructed none. Only one commercial-scale CCS power plant has been built worldwide to date, with a capacity of 110 megawatts (MW). This compares with a global installed capacity of wind and solar power of more than 550,000 MW.
The third and only remaining option is to stop building new coal-fired power plants and to phase out existing ones altogether. This makes all the more sense when considering the harm their air pollution causes to human health.
Many countries, developed and developing alike, have recognised this reality in the national climate action plans put forward in the run up to the Paris climate negotiations.
Offers like that of India show that countries see the opportunity to bring affordable electricity to the hundreds of millions of people still without power today using clean, renewable energy technologies. In fact, over the next 15 years, China and India alone plan to install twice the current global amount of wind and solar, whilst the economic advantages of coal are dissipating.
What these countries need now is not a promise of a false alternative, but global support and partnerships to turn their vision into practice. The US-India climate and energy partnership announced earlier this year provides an excellent example of how this can work.
It is clear that efficiency improvements to coal-fired power plants cannot deliver the emission reductions needed to stay within the carbon budget of a below 2 degrees world. As wind and solar power are racing ahead, the future role of coal in the global energy mix remains dependent on CCS becoming a hugely scalable solution.
Without an imminent though increasingly unlikely breakthrough in CCS economics however, this solution too will vanish, and with it the promise of clean coal.

(P.R. Shukla is Professor at the Indian Institute of Management, Ahmedabad, India and a lead author of the IPCC’s 2nd, 3rd, 4th and 5th Assessment Report. P.R. Shukla has served as a member of the Indian delegation to the UNFCCC at COP 8 and COP 9.
Dr Bert Metz is a Fellow of the European Climate Foundation and a member of several scientific advisory boards, including the Green Growth Best Practice Initiative. He was Co-Chairman of the IPCC Climate Change Mitigation Working Group from 1997 to 2008 and has served as chief negotiator for the Netherlands and the European Union on the UN Framework Convention on Climate Change and the Kyoto Protocol).

block