Background Information Document (Bid) August 2018
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BACKGROUND APPLICATION FOR POSTPONEMENT OF THE MINIMUM EMISSION STANDARDS (MES) FOR 14 INFORMATION OF ESKOM’S COAL AND LIQUID FUEL-FIRED DOCUMENT POWER STATIONS (BID) AUGUST 2018 Photo: by Witbank News In 2004, the National Environmental Management: Air Quality Act (NEM: AQA) (Act No 39 of 2004) was promulgated adopting a new approach to air quality management in South Africa to proactively protect the receiving environment PURPOSE OF THE BID In December 2009 the National Ambient Air Quality Standards (NAAQS) In 2004 the National were published under the NEM: AQA. The NAAQS established set limits This Background Information Document (BID) for priority pollutants in South Africa, and indicate what levels of presents an overview of Eskom’s reasoning for exposure to air pollution are generally safe for people, and the the postponement applications and to invite environment. your participation in the application process. In 2013 Minimum Emission Standards (MES) were published for air This BID contains the following information: pollution sources so as to achieve the NAAQS. The MES have two broad . A description of the Minimum Emission compliance timeframes, namely 1 April 2015 for ‘existing plant’ limits, Standards and what they entail, and more stringent ‘new plant’ limits which must be complied with by 1 . Why Eskom is not able to fully comply April 2020. with the timelines for existing plant standards and with new plant standards Since the 2015 limits are applicable to Eskom’s power stations, in 2014 coming into effect in 2020 , Eskom applied for postponements from the compliance timeframes for . What interventions Eskom will be 16 of its power stations in respect of particulate matter (PM), sulphur implementing to reduce emissions . Process to be followed in support of dioxide (SO2) and nitrogen oxides (NOx). The Department of Eskom’s application Environmental Affairs (DEA) granted 5 year postponements for most of the stations. Eskom currently complies with the emission limits as The BID further indicates how you can participate stipulated in the stations’ emission licences, but due to various existing and become actively involved in the process, and constraints, it is not possible for most of the power stations, to comply raise issues that may concern and / or interest on time or, in some cases, indefinitely, with the more stringent limits that you. come into effect from 2020. This BID is based on Eskom’s present approach and changes in the approach, based on inputs Accordingly, further postponements are required from 2020 from the from ongoing consultation with authorities and ‘existing ‘and ‘new plant’ limit compliance timeframes. Eskom intends to other role players, are possible. Substantive submit applications for postponement for 14 of its power stations to the changes would be reflected in future National Air Quality Officer at the DEA by 31 March 2019. communications in respect of this process. Prepared by Naledzi Environmental Consultants pg. 1 List of power stations which will form part of the postponement application This postponement application includes 11 of Eskom’s coal fired power stations in the Mpumalanga Highveld Region, one (1) station in the Vaal Triangle as well as one (1) liquid fuel-fired power station each in the Western Cape and Eastern Cape provinces. The power stations are listed in Table 1 and their geographic locations are indicated in Figure 1 and Figure 2. Tutuka’s postponement application process commenced in early 2018 and is running slightly ahead of the remaining postponement applications, and will be submitted before 31 March 2019, as required by the MES. Eskom submitted applications requesting postponement of the existing plant standards for Medupi and Matimba Power Stations in August 2017. The final response to those postponement applications is yet to be received. Table 1: Power Stations (and nearest large city) forming part of the postponement application Mpumalanga Highveld Region Vaal Triangle Region . Duvha (Emalahleni) . Lethabo (Sasolburg) . Kendal (Emalahleni) . Majuba (Amersfoort) Western Cape Province . Camden (Ermelo) . Acacia (Cape Town) . Grootvlei (Balfour) . Kriel and Matla (Kriel) Eastern Cape Province . Hendrina (Middleburg) . Port Rex (East London) . Arnot (Middelburg) . Komati (Middelburg) . Tutuka (Standerton) Figure 1: Map of the geographic locations of the various power stations forming part of this postponement application Prepared by Naledzi Environmental Consultants pg. - 2 - Figure 2: Map of the geographic location of the power stations forming part of the application within the Mpumalanga Highveld and Vaal Triangle Electricity generation process at the affected power stations and resultant emissions Coal Fired Power Stations: The electricity generation process at coal fired power stations includes converting liquid water to steam in boilers at the power station. As the water turns to steam it expands rapidly and rotates turbines connected to a generator that then generates the electricity. That steam is then returned to liquid water by cooling through large cooling towers. The process of converting water to steam requires heat energy which is obtained from the combustion of coal. This burning process produces ash and a range of combustion gases as by- products. A portion of the ash falls to the bottom of the boiler but the finer particles (referred to as ‘fly ash’) remain airborne and have to be removed from the gas stream before being emitted to the atmosphere. Eskom’s power stations make use of either electrostatic precipitators (ESPs) or fabric filter plants (FFPs) to remove at least 95% of the fly ash from the exhaust stream before it is emitted into the atmosphere. In addition to the fly ash (also referred to as particulate matter (PM)), the power stations also emit sulphur dioxide (SO2), nitrogen oxides (NOx) and other gases. PM, SO2 and NOx are regulated by the MES. These pollutants are emitted continuously as the power station operates. Liquid Fuel-Fired Power Stations: In gas turbine power plants, turbines are directly rotated by hot combustion gases. The station sucks in air from the atmosphere and compresses it. Liquid fuel is then injected and ignited. The gases expand and are channelled to turn the turbines to generate electricity. Prepared by Naledzi Environmental Consultants pg. - 3 - What are emission standards? In order to manage the air that we breathe, the authorities make use of two sets of standards, namely 1) ambient air quality standards and 2) minimum source emissions standards. Each of these is described in the following section. 1) Ambient Air Quality Standards: In managing air quality, authorities must ensure that the air inhaled by people does not contain more than a certain quantity of pollutant in every unit of air inhaled. That quantity of pollution per unit of air is expressed as the weight of the pollutant, typically, in micrograms per cubic meter of air, or μg/m3. Expressed in this manner, air pollution is referred to as a concentration. Authorities then use distinct standards to define the concentrations below which human health will not be adversely affected. These standards are called ‘ambient air quality standards’ and apply to the air to which people and the environment are exposed (breathed). National ambient air quality standards were published in December 2009, in South Africa. 2) Minimum Emission Standards: To manage ambient air quality, authorities must implement a system to control pollutants (source emissions) emitted into the atmosphere (atmospheric emissions) by industry. To do so, the maximum allowable emissions are typically prescribed, and in South Africa these have been translated into law as the Minimum Emission Standards (MES). The MES are expressed as concentrations, but since the concentrations are greater where they are emitted (before being diffused and diluted through the atmosphere), the standards are expressed in mg/Nm3 (see Box 1, below). The MES were published in April 2010 and amended in 2013. Box 1: Difference between μg/m3 and mg/Nm3 Grams are a measure of mass where the kilogram (kg) is the best known unit of measure of mass. There are then 1000 grams (g) in a kg. Equally 3 there are 1000 milligrams (mg) in a gram and 1000 micrograms (μg) in a mg. The N stands for ‘normal’ and refers to m of air at sea level at 0 ° C. The differences between the two standards are illustrated conceptually in Figure 3. Steam/Water Vapour from cooling towers Figure 3: Schematic illustration of the difference between emission and ambient standards Prepared by Naledzi Environmental Consultants pg. - 4 - What are the MES compliance timeframes? The MES have two compliance timelines (Table 2). 1) 01 April 2015: Compliance with ‘existing plant’ emissions All industrial operations triggering a listed activity as per the MES were required to comply with these standards. 1) 01 April 2020: Compliance with ‘new plant’ emissions Time from which all air pollutant emitters, (including existing plant) must comply with ‘new plant’ standards (more stringent limits). The MES included a provision for a postponement of the above mentioned limits and timeframes for compliance. The postponement is granted for a period of 5-years per application. Eskom has, in line with these provisions, requested the first postponement commencing in 2015 and is hereby requesting a second round of postponements for the next 5-year window commencing 2020. Table 2: Summary of the MES that apply to Eskom's coal (a) and liquid (b) fuel-fired power stations Table a): Coal fired plant Table b) Liquid fuel fired plant MES Max Release Rate (mg/Nm3) MES Max Release Rate (mg/Nm3) Compliance PM SO2 NOx Compliance PM SO2 NOx Timeframe Timeframe April 2015 100 3500 1100 April 2015 75 3500 1100 April 2020 50 500 750 April 2020 50 500 250 What would Eskom need to do to comply with the MES? In order to comply with the MES most of Eskom’s power stations need to install additional or upgrade existing emission control equipment used for the different primary pollutants.