Is there such thing as clean coal?
KKK seeks to address environmental issues through the lenses of science and to contribute in the clarification of these issues. It is motivated by the belief that the environment and progress are not zero-sum agendas, therefore a more holistic perspective is possible to minimize conflicts arising from divergent views. When issues arise or when there are diverging perspectives, KKK endorses the use of sound science in the consideration and resolution of the issues.
In recent years, energy supply has been pushed to the forefront of political discussion. The growing Philippine economy—with 2015 projections at 6.9% growth rate and a third credit rating upgrade in investment grade—requires long-term energy security; the high infrastructure and rapid urbanization ambitions that come with economic growth must be built on a stable supply of energy.
Coal is increasingly becoming a major source of energy for the country. According to the Philippine Energy Plan 2012-2030, coal contributes an average share of 30.1% to the country's primary energy supply. With the growing economy, demand for power is expected to grow at an average rate of 4.3% and requires new capacities totaling 13,166.7MW just to meet the domestic power requirement (energy demand and reserve margin).
Given the exigencies of this reality, coal is considered promising because it is a low-cost source of reliable base load energy. The cost factor continues to be a critical consideration for power customers especially in an emerging market such as the Philippines, and the widespread availability of coal as raw material and comparatively low capital investment make it an attractive option for investors over other energy sources.
As far as the Department of Energy is concerned, it is technology neutral and works with the private sector to develop a power mix to provide the country with a stable, reliable, and affordable electricity. In terms of coal, the government is optimizing the exploration, development, production, and utilization of indigenous coal reserves to lessen dependence on foreign supplies, increasing the production of indigenous coal by 100%. At present, imported coal contributes an average share of 70% to the country's supply requirements.
These major strides for coal-based power generation notwithstanding, it continues to be the topic of much debate and discussion as a number of coal projects are being pursued throughout the country. The Philippine energy landscape finds itself between two conflicting strides: those who support coal energy and those who oppose it.
At present, the landscape is looking significantly towards coal as a power generation solution, often under the premise, as well as promise, of the term, "clean coal." In keeping with the country's target economic growth outputs, key developments in coal production are touting dirty coal as a thing of the past, and "clean coal" is now a major contender for the country's long-term energy solutions.
But the talk around "clean coal" has come to raise variant views on the soundness of the fuel from environmental, health, and climate change perspectives. Many support the use of coal given such key improvements in technology. Department of Energy Secretary Carlos Jericho Petilla also argues that coal is an important source of fuel in the country; just as advanced countries are pushing for both coal and renewable energy, the Philippines can't rely on renewable energy alone.
Still, "clean coal" seems to be going around like a buzzword that shouldn't lure us like a light in pitch-dark. Environmentalists and anti-coal advocates are on the opposite end of Philippine industrialists, focused on its adverse environmental effects such as pollution. Following two sides of the same coin, is there, in fact, such a thing as clean coal?
The "clean" in clean coal
Ultimately, what is clean about coal is a single technology in a whole system. The "clean" in clean coal refers to the specific technology used, not the entire process by which coal (the raw material) generates electricity (the final product):
Here technology means the application of science so as to attain certain industrial objectives. Scientifically, there are measures by which to determine whether certain technologies really are "clean" or not: that is, firstly, the emissions that it generates, and secondly, its ecological effects.
When it comes to emissions, coal is indisputably a carbon-emitting technology, and it makes contributions to the global greenhouse gas (GHG) inventory in the form of carbon dioxide (CO2). The very term "clean coal technology" refers strictly only to the Circulating Fluidized Bed combustion system, which is the management of sulfur dioxide (SO2) and nitrogen dioxide (NO2) from the coal feed—both indirect greenhouse gas emissions. SO2 emissions are removed by allowing it to react with limestone; NO2 emissions are combined with oxygen through low boiler temperature.
The CFB combustion system is recognized by the International Energy Agency Clean Coal Centre (IEA CCC), but many other technologies are involved in overall coal production, including Particulate Removal Technology, Fly Ash Management Technology, Heated Water Management Technology, and so on—all of which are traditional technologies present in other industrial processes. What is "clean" in clean coal is anchored on a specific technology that manages certain emissions.
The role of coal plants
Just as clean coal technology is specific to a particular system, the effects of coal on human health, land, and water are specific to the power plants in which they are processed. A specific technology can be made clean, but the process by which an entire power plant operates must also be scrutinized. With 10 major coal plants throughout the Philippines, their operations should be fully compliant with environmental standards and limitations; they should not put human health at risk; and they should not degrade environmental resources.
The ecological and environmental impacts of coal are therefore significantly plant-specific. Indeed, these impacts on health and the environment constitute the more common concerns over the use of coal, and scientifically, they are dependent on factors such as how the plant operates, where the plant is located, what type of coal is being used, and so on. In fact, although SO2 emissions can be managed by the CFB combustion system and other similar technologies, they cannot remove the toxic elements of mercury, lead, arsenic, and chromium, which are released when coal is burned.
The impacts of coal production on land and water environment are likewise specific to the power plant. If harmful metallic substances are present in the coal feed, these will find their way into the ash residues generated in the boiler and can potentially leach into the land environment; this is dependent on the concentration and volatility of such elements. If heated water from the boiler is discharged into nearby bodies of water, with no cooling system to alleviate the thermal effects, it can potentially impact on marine life such as coral reefs that may be present in the area; this is dependent on the project site and the water waste management practices of the plant.
Coal quality is also a plant-specific factor, as the impurities present within coal vary from place to place. "Good quality coal," in this sense, is affected by the minerals in the soil, which compressed the dead remnants of plants and animals. Commercial considerations also influence the type of coal used—energy content, reliability of supply, transportation logistics, and pricing—which are all relative to a plant's operations. Using good quality coal is also necessary to avoid mercury problems.
All of the country's coal-fired power plants submit Self-Monitoring Reports (SMRs) that measure their compliance with environmental frameworks and policies, and given the fact that they continue to operate, it may be assumed that they are working within regulatory standards. A Multipartite Monitoring Team (MMT) and affected stakeholders are also implored to employ remedies if there are questions on the SMRs and opposing views on compliances.
To date, there are no evidences on acid rain effects, generation of organic toxics such as polycyclic aromatic hydrocarbons (PAHs), and radioactivity of Philippine coal power plants.
With the medium-, if not long-term trajectory of the Philippine energy landscape, the significant use of coal requires informed and responsible judgments on both sides. There is no doubt that coal emits carbon. But coal quality, hazardous wastes, and impacts on land and water environment vary from one power plant to another. Such key factors originate on a case-to-case basis because they are accounted for by operational and management practices—in the hands of power plants themselves.
Hence, when it comes to "clean coal technology," the more appropriate question to ask is not whether or not coal is clean; rather, can coal power plants be made clean? As the country faces an increasingly coal-fueled economy, can the growing number of coal plants assure us that they will strictly comply and subject their operations to the highest environmental standards, including their plant design, project site, and coal quality?
Public policy is established in order to ensure this compliance, but beyond standardized regulations, environmental guidelines can be strengthened by further integrating plant-specific factors—resulting in a more rigorous system that measures coal-fired power plants against their own conditions. Coal quality and coal procurement, for instance, should be measured and controlled, and specific environmental standards can be developed in relation to a plant's exact coal quality and procurement practices (to make sure, for instance, that plants are not sourcing their fuel from places where the coal contains mercury).
Coal Power Plants and Public Health
Concerns on public health are normally associated with metals that could potentially be discharged to the environment, principally mercury and lead. Methyl-mercury, the most toxic form of the metal can damage the central nervous system, brain and kidney on long-term exposure. Lead is a powerful cumulative toxicant that affects multiple body systems and is particularly harmful to young children. There is no known level of lead exposure that is considered safe. Lead in gasoline has been long banned in the Philippines and in several countries.
Key to an assessment of health effects is the presence or concentration of the elements in the coal feed. Using Lavoisier's universal law on "Conservation of Matter", when these elements are absent in the feed these cannot be present in the discharges or effluents from the coal power plant. However, if the elements are present in the feed their presence in the air can be determined through actual ambient air quality monitoring. Predictions can also be made on the basis of volatilization temperatures of the metals and the operating temperature in the boiler system of the power plant.
It is noted that the coal power plants in the Philippines are allowed to operate based on the monitoring reports that are regularly submitted to the EMB and the Multipartite Monitoring Team (MMT) which is the "watch dog" for performances of such plants
As part of the KKK advocacy, the concentrations of metals in ash which are not normally reported in SMRs should be strictly monitored. Under current practice, coal power plants are not recognized as generators of toxic and hazardous wastes. SMRs should also include metallic parameters when concentrations exceed the limits of Republic Act 6969 (Toxic and Hazardous Wastes) and should register the coal plant as such. The monitoring of the coal feed itself with respect to mercury, lead and other hazardous metallic elements/substances should be made part of the regulatory requirements. This is because the currently-employed coal power plant technologies do not include the removal of these metallic elements in the processing of coal into energy.
Mercury can find its way in the natural environment as illustrated by the mercury cycle below.
The greatest risk to humans is in mercury-contaminated fish.
Recent analysis of coal in a Philippine mining field reveals the absence or very low concentrations of metals, shown in the Table below:
The absence of Mercury (if "Non Detectable" in laboratory tests) in coal suggests that mercury will not be emitted in the air, water and land environment.
Lead is present in some coal samples. Its presence in the air environment is dictated by its volatilization/boiling temperature compared to the operating temperature of the power plant boiler.
Its presence and concentrations in the ash will be determined from actual analysis of ash or predicated through lead balance.
Table 1. Analysis of Metallic and Other Elements in a Luzon Mining Field Source: Private file of Dr E. G. Alabastro
Arsenic is present; analysis of its presence in the air, water and land environment can likewise be determined through analysis or by calculation through an arsenic balance.
The boiling point of lead is 1749 °C (3180 °F) while mercury boils at 356.73 °C, Methyl mercury at 230.66 °C and Arsenic is at 614 °C. These suggest that these elemental metals and compounds will not be discharged as air pollutants because the operating temperatures of Continuous Fluidized Bed Boilers for Coal Power Plants are lower than these temperatures.
The concentrations of elemental metals in the ambient air nearby an operating 200 MW Coal Power Plant are measured and results shown below:
Table 2. Measured concentrations of metals in ambient near adjacent to a Coal Power Plant
Source: Private file of Dr Ed Alabastro
The National Ambient Air Quality Standards for Source Specific Air Pollutants of the Phl Clean Air Act for lead is 20 µg/NcM and is not specified for mercury.
The Dutch Intervention Values are one set of international guidelines that prescribes the limits of concentrations of toxic pollutants in water and soil by which interventions e.g. remediation would be required shown in Table 3.
Table 3. Dutch Intervention Values of Selected Toxic Pollutants in Soil and Water
For coal power plants contamination of water bodies is highly unlikely because there are no waste water discharges. Normally cooling water is abstracted and returned back to a water body, e.g. a sea body but inasmuch as the cooling water does not come in contact with the coal concerns for water body contamination are largely unfounded.
Soil may be contaminated through the leaching of toxic components of ash. Ash is usually entombed in a landfill or maybe used as an additive in cement products.
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