The use of coal for energy generation is a major source of air pollution, causing illness and death. Burning coal in power plants emits hazardous outdoor air pollutants: particulate matter, sulphur dioxide, nitrogen oxides, carbon dioxide, mercury and arsenic. Soot pollution (PDF) stirred up during the coal mining process and in the transport of coal contributes to outdoor air pollution. While the use of coal for cooking and heating causes indoor air pollution.

In the US and China, coal is the single biggest source of outdoor air pollution. In India, there is little official data on air pollution but new satellite data shows that coal-fired power generation is a main driver of the country’s air pollution hotspots. In both Beijing and New Delhi, daily particulate matter levels are 1200% higher than World Health Organization (WHO) guidelines.

Air pollution causes 5.5 million premature deaths a year worldwide, with more than half of these deaths occurring in China and India. The burning of coal for power generation caused 366,000 premature deaths a year in China, between 80,000 and 115,000 in India, 22,900 in Europe, and 13,000 in the US.

In addition to premature deaths, coal-induced air pollution causes lung cancer and respiratory and cardiovascular disease. It reduces fertility and birth weight, and undermines the cognitive development of children. Communities living close to coal power plants also experience higher exposure to airborne pollutants, but a big share of pollutants causes health impacts over large distances and across borders .

The costs of these air pollution impacts on human health are high. The health bill of coal-fired power generation – which is not currently costed into health budgets – is estimated to be between €32.4 billion to €62.2 billion in Europe, and between $3.3 and $4.6 billion in India. Moreover, coal-linked air pollution affects agricultural and labour productivity : in Europe alone, it causes over 4 million lost work days a year. Technologies exist to reduce air pollutants from coal combustion, but often this equipment just transforms toxins into polluting wastewater (PDF).

Increased recognition of the health impacts of coal’s air pollution, alongside the availability of sustainable, reliable, affordable energy alternatives, is a strong driver to move away from coal. Beijing, for example, closed all of its coal fired power plants to reduce air pollution in 2015. In contrast, renewable energy technologies cause virtually zero air pollution (PDF).

Air pollution, including from coal, affects everyone, but it harms poor populations more than rich populations. Typically, poor people are more exposed to air pollution and more susceptible to its health impacts with lower access to health services and fewer resources to pay for them.

Approximately 98% of cities in low- and middle-income countries do not meet the WHO’s air pollution guidelines, compared to 55% in high-income countries. Air pollution levels continue to rise in the world’s poorest cities. Within these polluted cities, poorer families are more likely to live close to industrial sites, power stations and other sources of air pollution because these areas tend to be cheaper.

Low-income households, and particularly poor rural communities with little or no access to electricity, are also more likely to use coal and other solid fuels for cooking, lighting and heating. The use of these fuels caused approximately 4.3 million premature deaths in 2012, with women and children more exposed to smoke from coal fires in their homes than men.

Poor people are also the most vulnerable to air pollution. Limited economic resources result in poorer health overall and poor people often face difficulties accessing health services. People in London’s poorest areas are twice as likely to die from lung disease than people living in richer areas because of the city’s air pollution (mostly caused by transport).

Reducing outdoor air pollution – by shutting down coal plants and replacing them with cleaner energy sources – can, therefore, help reduce the health inequalities caused by air pollution.

The coal sector withdraws, consumes and pollutes large volumes of freshwater at every stage of its life cycle. Before coal is mined, mining companies drain or pump groundwater dry to enable extraction. Polluted water can seep from mines and pollute nearby bodies of water. Once mined, coal ore must be washed before use, creating a toxic slurry that needs treatment. Cooling coal power plants also requires vast quantities of water, enough to suck an olympic-sized swimming pool dry every three minutes. Further still, burning coal produces emissions that cause acid rain and acidification (caused by higher atmospheric CO 2 concentrations) of bodies of water.

In 2013, the coal industry accounted for 6.8% of all water withdrawal globally, and 11.2% in the water catchments where coal plants are located. The industry’s water consumption (the amount withdrawn that is not returned), amounts to 22.7 billion m3 (cubic metres) per year, enough to meet the basic water needs of 1.2 billion people. Coal-fired power plants account for 84% of this consumption; mining for the rest. The additional coal plants being proposed would see the industry’s water withdrawal double in the next 20 years.

Morever, roughly 44% of existing and planned coal plants are located in areas with high to extremely high water stress, while 25% are located in 'red-listed’ areas, where surface and groundwater resources are at risk of drying up because water is being withdrawn faster than it can be replenished.

In China, nearly half of its existing and proposed plants are in red-listed areas. In India, a quarter are in red-listed areas. Since 2010, water scarcity has forced the Indian government to suspend numerous coal plants, leading to rolling blackouts. In some states, prolonged droughts have already led India to question the viability of coal-fired generation.

The coal industry’s global water consumption could be nearly halved by retiring all plants aged over 40 years and by replacing all plants in red-listed areas with energy alternatives that require little water, such as wind and solar PV.

The coal industry’s unsustainable water demands can have severe impacts on poor and vulnerable groups. Where water resources are scarce, competition with coal plants for water consumption increases communities’ vulnerability to droughts. It also reduces water availability for basic residential needs and for agriculture, the main source of income for many poor families.

Coal plants directly compete with farmers for scarce water resources, leading to political tensions and social unrest. In India’s Vidarbha region, farmers have struggled to irrigate their lands, yet the government continues to plan to build 71 new coal power plants in the region. These plants would consume a total of 40% and 14% of the future irrigable water from the region’s Wardha and Wainganga rivers, respectively – enough to irrigate 410,000 hectares of farmland. In regions like Vidarbha, coal expansion threatens to exacerbate water and agrarian crises, placing additional stress on poor farmers.

The coal industry’s discharged wastewater also threatens agriculture and drinking water safety. Several cities along China’s Yellow River have had their drinking water cut-off due to coal industry pollution.

The impacts of coal mining on water resources can also harm poor and vulnerable communities. Until recently, Colombia’s Cerrejón coal mine – one of the world’s largest open-cast coal mines – planned to divert 24 km of the Ranchería River in order to extract the coal beneath it. By the company’s own estimates, the plan would reduce the natural aquifer by 40%, the consequences of which would be ‘devastating and irreversible’ according to research scientists in the region’s university. The river is also sacred to the indigenous Wayúu people. An open letter from local indigenous organisations to Colombian President Santos, called for the suspension of the project, stating ‘if the expansion takes place, the living conditions of the majority of the inhabitants of Guajira will worsen even further’.

The project to divert the river in Colombia has been shelved for now, due partly to a decline in international coal prices as the US and EU increasingly demand cleaner alternatives to coal. However, these conflicts serve to highlight the risks posed by the coal industry to vulnerable communities.

Coal mines have forced the displacement of numerous communities throughout the world. In India alone, mining uprooted 2.55 million people between 1950 and 1990 as coal mines proliferated, shifting from underground to open-pit mines, and growing exponentially in size . In Colombia in 2010, the government ordered three rural towns to resettle because of air-toxicity levels in the area caused by coal dust.

Displacement continues today. A planned open-pit coal mine in the Phulbari areas of north-west Bangladesh threatens to immediately displace 50,000-130,000 people (PDF). Over 220,000 people could be indirectly affected by deteriorated water resources (PDF) and the effects on irrigable land, forcing further migration.

Mining-induced displacement is not limited to developing countries. However, displaced families tend to fare better in countries with stronger democracies, effective rule of law and human rights protections. Typically, in poor countries, laws covering involuntary resettlement for industrial projects are weak or non-existent.

Countries that lack sufficient capital to develop their own mining industries often invite foreign investment, relinquishing profits to foreign corporations in return for the hope of tax revenues and jobs. But tax exemptions to draw in multinationals often result in much less tax revenue to serve the public, as seen in the case of the Columbian government in 2007 and 2009, appearing to have paid corporations to take its coal. Globally, tax revenues from mining have been diminishing.

Mining does not necessarily improve the welfare of local communities either. Mining jobs require skills that local residents often do not have, and only last until the mine is retired. The social impacts and environmental damages of coal mining, however, tend to be long term. Nevertheless, the transition to low-carbon energy will need to be equitable and provide alternative job opportunities for those currently employed in the coal industry.

Coal mining generally occurs far from urban centres where governments have limited capacity to regulate the industry. These rural areas are often home to poor and indigenous communities that lack financial and political power. Many public authorities tolerate abuses  of human rights and environmental destruction out of fear of losing tax revenues. As a result, even when displaced populations are compensated for their lost property, that compensation is consistently inadequate.

Our planet is limited to a ‘carbon budget’ of emissions to keep global warming to a ‘safe level’ of below 1.5°C to 2°C mean temperature change. In all countries, emissions must peak well in advance of 2050. By 2100, net emissions must be reduced to zero.

Without dramatically phasing down coal power, we will not avoid catastrophic climate change. Existing infrastructure, largely coal, will produce enough emissions to exhaust between 70% and 90% of our 2°C carbon budget, if used to the end of its productive life cycle (see Figure). To have a better than 50% chance at keeping the global mean temperature change below 2°C, almost nine-tenths of known coal reserves are unburnable and must remain in the ground.

This will require stepping up the decommissioning of coal plants, with the developed world leading, given their responsibility as the historical ‘big emitters’. However, this is not happening and new plants are still being planned and built – mostly in the developing world.

Such an expansion is untenable. If only one-third of this planned construction occurred, there would be no room in the carbon budget for emissions from other activities such as driving, flying, agriculture, producing lumber, paper, cement, or metals.

Most of the planned pipeline of projects are in developing Asia, with 67% of new plants planned in India and China alone. As World Bank President Jim Kim stated in a recent speech, ‘If the entire region implements the coal-based plans right now, I think we are finished … That would spell disaster for our planet’.

Power generation does not have to continue with business as usual. Unlike other sectors, there are many low-carbon alternatives. Electricity produced from renewable energy is now frequently cheaper than coal power and further rapid innovations will continue to drive prices down (see 'Can ‘clean coal’ provide a solution to these problems?' below).  

A changing climate will impact everyone, but it is already having the biggest impact on poor communities with the fewest resources to adapt. Over two in five of the people most vulnerable to climate change are already surviving on the edge of subsistence. Of the 30 countries most vulnerable to natural disasters and a changing climate, 26 are least developed countries. Climate change threatens to undermine the productivity of global marine and terrestrial food production systems (see 'How will climate change impact food production and security?' below).

Climate change is also projected to increase illnesses that disproportionately affect the poor. Global warming of 2-3°C could increase the number of people exposed to malaria by 150 million. Higher temperatures and water scarcity will also inhibit hygiene and sanitation, increasing other pathogens. Outbreaks of schistosomiasis and cholera could become more frequent and the burden of diarrhoea could increase by 10%, with children being the most vulnerable. Healthcare expenses already push over 100 million (PDF) people into poverty each year. This number is likely to escalate with climate change.

Other climate-related shocks – floods, droughts, storms, heatwaves and pests – can also destroy the crops and homes of vulnerable families, driving them into extreme poverty. These shocks are expected to increase in severity and frequency (PDF) as a result of climate change. When disasters hit, poor families lose a greater portion of their income and assets compared with richer families. In addition, poor people tend to have lower quality homes that are less resilient to natural hazards, and fewer safety nets such as insurance, savings or support from government programmes. Droughts alone could pull 100-150 million people deeper into poverty each decade.

The World Bank estimates that, without measures to protect poor families from its impacts, climate change could result in more than 100 million additional people living in extreme poverty by 2030. If left unchecked, climate change could help wipe out current gains in eradicating extreme global poverty and push up to 720 million people back into extreme poverty between 2030 and 2050. Africa and South Asia are the most vulnerable regions.

In sub-Saharan Africa, South and South-East Asia and China, roughly 2.7 billion people depend on agriculture, livestock and fisheries for their main source of income. Climate change-induced declines in agriculture, livestock and fishery yields could prevent 250-500 million people from escaping poverty for decades.

Climate models predict global crop yield losses of 5% by 2030 and 30% by 2080 due to climate change, even if farmers adapt by changing crop varieties or increasing irrigation. Across rain-fed farms in Africa, the failure rate of the primary growing season will increase from 1 in 5 years today to 1 in 3 years, in a 1.5°C to 2°C warming scenario.

Climate change will also impact fisheries yields, exacerbating overfishing and other pressures. Even under the most optimistic projections, warming oceans and ocean acidification will cause a 50% loss of coral to bleaching by 2050, destroying the habitats of near shore fish species. Warming ocean temperatures will lead to a poleward shift in the distribution of pelagic fish species, undermining the deep sea fisheries of developing countries. In a higher emissions scenario, productivity of coastal fisheries in the Pacific is projected to decrease by 10 to 35% (PDF) by 2100.

Poor farmers and fishermen suffer directly from declines in production caused by climate change. In Uganda, a 10% decline in water availability was shown to reduce crop income by 14% overall, and by 20% in the poorest households.

Lower agriculture and fishery yields are likely to exacerbate food insecurity in sub-Saharan Africa and Asia. High food prices disproportionally affect poor families, who spend a greater portion of their income on subsistence. The 2008 food price spike impoverished 100 million people.

Largely as a result of reduced crop yields, climate change is expected to increase undernutrition and cause severe stunting in an additional 7.5 million children by 2030. In a 2°C warming scenario, as many as 120 million children could be malnourished in each subsequent decade, and 30-40 million stunted, likely reducing their educational attainment and incomes in adulthood.

The coal industry argues that more efficient and less polluting ‘advanced coal’ will help reduce carbon emissions and other pollutants. Decades of research, development and innovation have greatly advanced the thermal efficiency of coal power. The newest ‘advanced coal’ plants produce 40% less CO2 than conventional ones.

Yet despite this improvement, advanced coal is neither clean nor cheap enough to offer a viable solution. In even the most advanced coal plants, the life cycle emissions are around 30 times higher per kilowatt-hour than those of wind and hydro power, 20 times higher than solar and geothermal power, and 50% higher than natural gas.

It is a similar story for coal’s other air pollutants. Mandatory ‘scrubbers’ could remove air pollutants produced by coal plants, but at an additional cost. In contrast, air pollution from renewable energy technologies is, essentially, zero (PDF).

The US Energy Information Administration calculates that unsubsidised electricity produced by onshore wind, and geothermal in the US is cheaper on average than even conventional coal technologies. These technologies, along with unsubsidised solar, are cheaper than advanced coal.

Elsewhere, the economics of advanced coal power are even worse than in the US, which is one of the cheapest places to build an advanced coal-fired power plant. In the developing world, coal is usually more expensiv (PDF) (especially when imported), lower quality (thus less efficient and more polluting); and generally, coal plants remain dormant (not generating income) for a greater amount of time.

In India, for example, the minister responsible for both new coal and renewable power development recently stated, ‘I think a new coal plant would give you costlier power than a solar plant’. His statement is supported by the extremely low bid prices for recent solar procurements in India.

A future powered by advanced coal is neither affordable nor compatible with safe levels of CO2 emissions and there are much better and more cost-effective energy sources available.

Carbon capture and storage (CCS) is the process whereby CO2 is captured from a large emitter, such as a coal plant, transported and then injected into deep geological formations for permanent storage. If it became commercially viable within the timeline needed to stay within our remaining carbon budget , CCS could potentially help prevent CO2 emission from energy or industrial processes (PDF) that lack low-carbon alternatives, from reaching the atmosphere.

However, the coal industry argues that coupled with advanced coal technology, CCS will offer a technological option to deal with coal emissions ‘further down the track’. This is a fallacy.

While many elements of the CCS process have been tried and tested, the only project operating the ‘full chain’ of CCS processes – capturing the CO2, transporting it to a geologically appropriate site, and injecting it for permanent storage – is the state-owned Boundary Dam project in Canada. Partially funded by government subsidies, technical problems in design and operation have prevented it from operating at full capacity and have led to considerable cost overruns.

Viable CCS remains at least a decade away. Moreover, if CCS proves technologically and commercially viable, modelling shows that 82% of known coal reserves would still be unburnable because of the slow roll-out of CCS.

Even after CCS is ‘proven’ to be technologically feasible, it will still need to be proven commercially viable. In the US, the capital costs of CCS are roughly double that of an unabated coal-fired power plant. With coal generation already facing stiff competition from renewable technologies that are cleaner and in many cases cheaper, it is unlikely that CCS will ever be a viable option for coal power. Given this reality, 80-90% of the $8.1 billion in public funding for CCS for power projects remains unclaimed by private investors

There are some good reasons for further public investment in CCS research and development for applications like niche industrial processes that do not have economically viable low-carbon alternatives. However, CCS does not justify further coal expansion.