1. Introduction
Global greenhouse gas (GHG) emissions can be attributed to different sectors of the economy. Measuring these emissions has been useful to provide information on emission sources and their contributors to total emissions. The service sector in addition to the manufacturing industry has been highlighted as a major contributor to GHG emissions due to the rapid economic shift from manufacturing to the service industry, especially due to heavy energy consumption. GHG emissions are more than doubled when imported inputs are included on a consumption basis for the service industry (Roberts et al. 2021). Therefore, GHG measurement is important in identifying areas with mitigation opportunities. In addition, it is becoming critical and often mandatory in many countries to report on GHG measurement and GHG management to reduce emissions and track progress toward targets of carbon neutrality and net-zero emissions.
A standardized methodology is essential to measure and report GHG emissions and reductions. Consequently, specifications have been developed with guidance at the organizational level for the quantifying and reporting of greenhouse gas emissions. Typically, GHG emission sources can be divided into three scopes. Scope-1 emissions are direct GHG emissions that occur from sources that are controlled or owned by an organization, such as emissions associated with fuel combustion in boilers, furnaces, or vehicles. Scope-2 emissions are indirect GHG emissions associated with the purchase of electricity, steam, heating, or cooling. Scope-3 emissions are the result of activities from assets not owned or controlled by the reporting organization, covering all other indirect emissions from the value chain (GHG Protocol and Carbon Trust Team 2013). Scope-3 emissions include all sources not within an organization’s scope-1 and scope-2 boundaries and can be significant, for example, in health care services (Tennison et al. 2021), knowledge organization (El Geneidy et al. 2021), prosecution services (Virgens et al. 2020), conservation and maintenance services (Alvarez and Rubicon 2015), and tourism (Rico et al. 2019).
Recently, the International Organization for Standardization (ISO) 14064-1:2018 was revised to include not only scopes 1 and 2 but also scope-3 emissions, requiring an organization to determine which indirect emissions are to be included in its GHG inventory, especially the GHG emissions sources in scope 3. As part of this process, the organization must define and explain its own predetermined criteria for the significance of indirect emissions, by not excluding substantial quantities of indirect emissions or evading compliance obligations. Criteria used to evaluate the significance of indirect emissions may include the following: (i) magnitude, where the indirect emissions or removals are assumed to be quantitatively substantial; (ii) level of influence, considering the extent to which the organization can monitor and reduce emissions and removals; (iii) risk or opportunity, where the indirect emissions or removals contribute to the organization’s exposure to risk or its opportunity for business; (iv) sector-specific guidance, where the GHG emissions are deemed significant by the business sector, as provided by sector-specific guidance; (v) outsourcing, where the indirect emissions and removals result from outsourced activities that are typically core business activities; and (vi) employee engagement, where the indirect emissions could motivate employees to reduce energy use or generate team spirit around climate change (International Organization for Standardization 2018).
In addition, several studies have confirmed that the contribution of scope-3 GHG emissions in the service sector could be large. A study on GHG emissions of the national health care service in England by Tennison et al. (2021) included scopes 1, 2, and 3, covering personal patient and visitor travel. It was reported that the supply chain category was the largest source of health care GHG emissions, accounting for 62%, with these emissions coming from the supply chain category mainly from the manufacturing of pharmaceuticals and chemicals (32%), medical equipment (19%), and business services (17%). Similarly, El Geneidy et al. (2021) reported that most of the GHG emissions of a knowledge organization belonged to scope 3, due to travel-related activities (87%). Virgens et al. (2020) demonstrated that scope-3 emissions accounted for 83% of total GHG emissions from the Brazilian prosecution service. Their results showed that the emissions from purchases in the products/services category were responsible for 50% of total scope-3 emissions, which mostly came from the purchase of low-mobility services (e.g., advertising, banking, and computerized systems). The second contributor to scope-3 emissions was the employee commuting category. Alvarez and Rubicon (2015) conveyed that scope-3 emissions represented the biggest share of the overall organizational carbon footprint of conservation and maintenance services due to the consumption of purchased materials for delivering the services (approximately 50%). Rico et al. (2019) concluded that 93% of the GHG emissions of Barcelona’s tourist activity were from the activities in scope 3, attached to the combustion of fuel for arrival and departure transport. Radonjič and Tompa (2018), studying the telecommunication service, pointed out that scope-3 emissions were the second largest contributor to total GHG emissions, which were dominated by employee commuting and downstream leased assets. Abeydeera and Karunasena (2019) assessed the carbon footprint of hotel operations in Sri Lanka and found that the highest contribution to GHG emissions was from scope 2, which was caused by the consumption of purchased electricity and gas used for electrical equipment and gas appliances in hotels. The contribution of scopes 1 and 3 to the GHG emissions of the hotels was similar and considerably lower than that of scope 2, because transportation activities (staff commuting and guest travel) were not included in the carbon footprint calculation.
With the aim of reducing GHG emissions, numerous studies have concentrated on implementing GHG reduction measures related to energy use or energy efficiency (Tennison et al. 2021; Rico et al. 2019; Hu et al. 2015), as well as travel modes (Geneidy 2021). Rico et al. (2019) suggested that if 20% of passengers chose to fly on airplanes that offset their flight emissions, the scope-3 GHG emissions of Barcelona’s (Spain) tourist activity could be reduced by approximately 736 701 tCO2 annually. Another option that could be implemented to reduce GHG emissions from scope 3 was using biofuel instead of kerosene for aviation. Tennison et al. (2021) reported that improvements in the energy system helped to decrease the total carbon footprint of the National Health Service in England by about 26%. Several measures have been recommended, such as switching to lower-carbon energy sources, reducing the use of single-use consumables, upgrading the building envelope, and improving appliance efficiency to reach net-zero emissions by 2050 under the U.K. government’s commitment. Hu et al. (2015) found that the main source of carbon emissions in the accommodation services of an international tourist hotel resulted from the use of electricity (scope 2). The GHG reduction measures implemented included improving energy use in lighting and air conditioning systems and managing the consumption of hotel amenities. This resulted in the carbon emissions of a one-night stay in a standard room decreasing by 21.94%. However, the annual carbon footprint of the accommodation service at the hotel significantly increased due to the increase in the occupancy rate. A study by Fernández and Roqueñí (2018), focusing on measures to reduce the GHG emissions of supermarkets in Spain, included several measures to improve energy efficiency. The results showed that the replacement of multicircuit refrigeration facilities for refrigeration plants could reduce CO2 emissions by 27%, and the installation of LED lamps for lighting throughout the supermarket could provide a reduction of 26% in CO2 emissions. About 17% of CO2 emissions could be reduced by using insulated cooling and freezing cabinets equipped with doors and glass. El Geneidy et al. (2021) provided some potential mitigation strategies to reduce the carbon footprint of knowledge organizations, which mainly focused on travel-related emissions. The most effective measure was to halt all travel, which was a practical measure during the COVID-19 pandemic. Another option to reduce the carbon footprint was to avoid travel via airplane to reduce flight-related emissions. Furthermore, considering environmentally friendly commuting modes helped to reduce the carbon footprint generated by employees commuting to work.
This review shows that the service industry has been focusing on reducing GHG emissions from their operational control activities (scope 1) and the purchase of electricity, heat, and steam (scope 2). However, the contribution of scope-3 GHG emissions from all indirect emissions (not included in scope 2) associated with emissions from upstream (production of purchased products or raw materials and transport of purchased products) and downstream (transport for distribution, use of produced products, and final waste disposal) is also important and should not be overlooked in GHG measurement and management. In this context, the current study was developed to explore the GHG emission sources associated with activities along the whole value chain in scope 3 for supermarket retailing and the practical issues of a methodology to identify the significant levels of emissions. Information on the contributions to scope-3 GHG emissions from all indirect emissions (not included in scope 2) that occur in the value chain of the reporting company, including both upstream and downstream emissions, will facilitate the inclusion of indirect emissions. In addition, it could be very useful for deriving GHG mitigation measures for more efficient GHG reduction strategies, tracking progress toward the reduction targets, and moving toward climate goals with regard to carbon neutrality and net-zero emissions.
2. Materials and methods
The GHG emissions of a supermarket retail operation were assessed according to the method described in the National Guideline of Organizational Carbon Footprint that includes GHG emissions in scope 3 (indirect emissions, as defined in the ISO 14064-1). GHG measurement involves a multistep process, as follows: (i) defining the reporting boundaries and GHG inventories, (ii) identifying the GHG sources and sinks, (iii) quantifying the GHG emissions, (iv) developing GHG reduction initiatives and projects, and (v) ensuring the GHG inventory quality management. In the current study, the supermarket retail operation examined had a stand-alone location with a total area of 15 492 m2, chosen mainly due to the ease of data collection and the implementation of GHG reduction projects. Figure 1 shows the studied supermarket retail site in a rural area at least 10 km from local communities, with natural surroundings and no industrial factories nearby. Figure 2 shows the area allocation into two parts: 4722 m2 as the display area (for the sale of their own products), 8526 m2 as the rented area (for the sale of other products by tenants), 1661 m2 for warehouses, and 583 m2 for offices. The study considered a daily operating time of 12 h. The indirect GHG emission sources associated with the whole value chain of the selected supermarket were identified (Table 1) using the national guideline of listed activities causing indirect GHG emissions but were not limited to that.
The location of the supermarket retail operation in the study.
Citation: Weather, Climate, and Society 15, 3; 10.1175/WCAS-D-23-0012.1
The layout of the supermarket retail operation.
Citation: Weather, Climate, and Society 15, 3; 10.1175/WCAS-D-23-0012.1
Scope-1 and scope-2 GHG emission sources of the supermarket retail operation; LPG = liquefied petroleum gas.
Based on the ISO and national guideline requirements, a scoring matrix was applied by considering the magnitude of emissions, the level of influence, and the risks/opportunities associated with business operations. These were given priorities based on the supermarket retail context to assess the importance of scope-3 activities. The required inventory data were mainly collected from the internal data recording systems of the supermarket. The GHG inventory data were collected from purchase orders, receipts (purchased goods and services), reimbursement from employees as petty cash, and records from operation and maintenance activities. Upstream logistics were calculated using the fuel consumption rate and the transport distance, which was allocated according to the number of stops for each shipment. Customer travel to and from the retail store was based on a proxy estimation by assuming an average distance of 10 km within the radius around the store for marketing activities. A literature review was used to calculate the energy consumption from the use of sold products and from the waste management system for packaging to assess GHG emissions from an end-of-life treatment for packaging (GHG Protocol and Carbon Trust Team 2013).
The identified GHG emission factors (EFs) are listed in Table 2. For scopes 1 and 2, the EFs were generally gathered from the national life cycle inventory databases and supplemented by international databases, when necessary.
Emission factors for scopes 1–3 used in this study (Thailand Greenhouse Gas Management Organization 2022).
Scope-3 GHG emissions included all sources that are not within the organization’s scope-1 or scope-2 boundaries. There are at least 15 categories of scope-3 GHG emissions suggested in the GHG Protocol, although not every category is relevant to all organizations. In the current study, the scope-3 GHG emission sources were identified according to the organization’s activities based on the guidance from the GHG Protocol, without overlooking other sources not mentioned. The scoring matrix analysis was used to assess the significance level of the scope-3 GHG emission sources by considering the following selected criteria for significance evaluation: magnitude (quantity level of GHG emissions), reduction potential (potential GHG reduction resulting from applied measures), and risks/opportunities for business operations. The scope-3 GHG emission sources were identified, and the significance levels were denoted using a scoring system. For each criterion, a score of 1 indicated low GHG emissions, low GHG reduction potential, and low risk or low opportunity for business operations; a score of 3 indicated medium GHG emissions, medium GHG reduction potential, and medium risk or low opportunity for business operations; and a score of 5 indicated high GHG emissions, high GHG reduction potential, and high risk or low opportunity for business operations. The sum of the scores for all criteria was defined as the total score, with a total score in the range of 7–15 considered to be significant, whereas a total score below 7 was considered not to be significant.
3. Results
The identified GHG sources in scope 1 were the fuel used from company-owned and employee-owned vehicles for transportation, the fuel used from the operation of equipment, and fire-drill training and fugitive emissions from air conditioning units, refrigeration systems, fire-suppression equipment, septic tanks, and wastewater treatment. Scope-2 GHG emission sources included the indirect emissions from the production of purchased electricity that was consumed by equipment and the operation of the supermarket. For scope-3 GHG emission sources, significant levels were identified in the categories of purchased goods and services, fuel- and energy-related activities, waste generated in operations, business travel, and downstream transportation and distribution (Table 3). Significant levels were also found in the category of waste generated in the operations, resulting from a high magnitude of emissions with a high reduction potential. However, upstream transportation and distribution, capital goods, and employee commuting, for example, were deemed not significant, meaning that their share of GHG emissions was less than 5% in comparison with scope-1 emissions combined with scope-2 emissions, due to their low GHG reduction potential and their low risk for business operations. In addition, the use of sold products and the end-of-life treatment of sold products were significant because the emission factor used for calculating the category of purchased goods and services already included use and the end-of-life phase of the product life cycle.
Scope-3 GHG emission sources of supermarket retail operation and scoring matrix analysis to evaluate significance level. Here, Y = yes (included), and N = no (excluded). For magnitude, 5 indicates contribution of GHG emissions of >40% (combined scopes 1 and 2), 3 is contribution of GHG emissions of 5%–40% (combined scopes 1 and 2), and 1 is contribution of GHG emissions of <5% (combined scopes 1 and 2). For reduction potential, 5 indicates action plans and targets to reduce GHG emissions, 3 represents potential GHG reduction measures that can be applied but no action plans, and 1 indicates no action plans to reduce GHG emissions at all. For risk or opportunity, 5 corresponds to high risk/low opportunity for business operations, 3 corresponds to low–medium risk/medium opportunity for business operations, and 1 corresponds to irrelevant.
The calculations of total GHG emissions from the supermarket retail operation showed that scope-3 GHG emissions accounted for the largest proportion (94%) of the organizational carbon footprint of the supermarket (Table 4). The direct emissions (scope-1 GHG emissions) and indirect emissions (scope-2 GHG emissions) were considerably lower than the scope-3 GHG emissions, due to the large GHG emissions generated from the upstream and downstream activities of the organization, including purchased goods and services, use of sold products, end-of-life treatment of sold products, and waste generated in operations. In addition, fugitive GHG emissions generated the largest proportion of the scope-1 GHG emissions, which resulted from energy and coolant use for the refrigeration system and air conditioning equipment.
GHG direct and indirect emission sources of supermarket retail operation.
The largest GHG emissions of the scope-3 sources were in the category of purchased goods and services, use of sold products, and end-of-life treatment of sold products, accounting for 52%, followed by the waste generated in operations category at 33%, downstream transportation and distribution at 8.7%, the fuel- and energy-related activities category at 0.8%, and finally business travel at 0.01% (Fig. 3). The major contributor to the category of purchased goods and services was the acquisition of purchased goods, at almost 100%.
An analysis of contributing GHG emissions for the supermarket retail operation.
Citation: Weather, Climate, and Society 15, 3; 10.1175/WCAS-D-23-0012.1
The current study divided the food products on the supermarket shelf into nonchilled and chilled food to facilitate data collection, as well as the calculation of GHG emissions. The category of nonchilled food items included juice, milk, coffee, soft drinks, tonic drinks, alcoholic beverages, sport/energy drinks, tea, water, snacks, noodles, rice, seasonings, sugar, and cooking oil, as well as personal care products, such as toothpaste, shampoo, facial tissues, and sanitary pads. Pet food and household cleaning products were also listed in the category of dry food. Chilled food items included vegetables, fruits, meat, fish, frozen fruits and vegetables, fresh milk, dry ingredients, eggs, cheese, yogurt, frozen appetizers, desserts, and packaging, including plastic wrap, plastic bags, plastic boxes, and paper boxes. The different types of goods a retailer offers were divided into three categories: hard line, soft line, and home line. The purchased goods listed in the hard-line category included electronic accessories and home appliances, such as air conditioners, washing machines, refrigerators, electric fans, vacuum cleaners, rice cookers, and radios. Soft-line goods included clothing, inner wear, umbrellas, and handbags. Several items, such as dinnerware, glassware, toys, bedding equipment, stationery, carpets, furniture, and car accessories, were included in home-line goods. The category of pharmacy included drugs intended for external or internal use. As depicted in Fig. 4, the category of nonchilled food items had the highest GHG emissions among the purchased goods, accounting for about 85% of total GHG emissions. Hard-line goods (e.g., microwaves, hair dryers, cookstoves, and vacuum cleaners) accounted for approximately 9.5% of total GHG emissions from the production of purchased goods, while soft-line (e.g., pajamas, T-shirts, socks, and umbrellas) and home-line goods (e.g., scissors, pens, pencils, and rulers) accounted for 1%–2% of the total carbon footprint for total purchased goods. The category of fresh food contributed a relatively small proportion (2%) in comparison with the nonchilled food category. The pharmacy category made the lowest contribution of about 0.05% to the total carbon footprint for purchased goods.
The proportion of GHG emissions generated by each type of purchased goods in the supermarket retail operation.
Citation: Weather, Climate, and Society 15, 3; 10.1175/WCAS-D-23-0012.1
4. Discussion
The hotspots generating major GHG emissions, especially from scope-3 activities, for GHG management and reduction were purchased food products and expired goods. It was suggested that the supermarket should primarily source purchased products carrying a carbon footprint–reduction label; a list of labeled products is available from the published database of the Thailand Greenhouse Gas Management Organization. The potential GHG reduction was calculated by referring to the requirement for a carbon footprint–reduction label to reduce at least 2% of the life cycle GHG reduction from the application of GHG reduction measures in the previous year or within 2 years. The potential GHG reduction was calculated using a 2% GHG reduction with the total sold products. The results showed that the GHG emissions of dry food and fresh food could potentially be reduced by 321 and 43 kg CO2 emissions yr−1, respectively, with no impact on the cost, because the certified products are sold at the same prices as noncertified products (Table 5). More important, customers should be educated to support the manufacturers producing low-carbon products by making purchasing decisions based on certified carbon-reduction labels.
Potential GHG reduction emissions from purchased food products carrying carbon-reduction label.
The other focus for GHG reduction was linked to the expired goods (dry food and fresh food) that resulted from overstocking or unexpected market situations, such as the COVID-19 pandemic. In Swedish supermarkets, unsellable products due to a passed best-before date, damage or color change of the product, and food rejection upon delivery contributed around 140 tCO2e to the entire carbon footprint of one supermarket. The categories of fresh fruits and vegetables and meat had the biggest contribution to the carbon footprint of food wasted in the supermarket, accounting for 46% and 29%, respectively (Scholz et al. 2015). Food waste reduction measures also help to mitigate indirect GHG emissions from waste management. This was consistent with suggestions from other studies. For example, Eriksson and Spångberg (2017), focusing on waste management of fruits and vegetables, found that food donation was the better option, as it caused fewer emissions than energy-recovery methods (e.g., incineration and anaerobic digestion). The carbon footprint of food and packaging waste management was evaluated by Marrucci et al. (2020), who reported that 63% of overall waste was organic matter and that anaerobic digestion enabled larger GHG savings than did composting. Lowering the prices of about-to-expire food products in retail stores is another possibility that helps reduce food waste while maintaining high profits (Sakoda et al. 2019). Artificial intelligence (AI) technology could be applied for tracking a product’s expiration date. Supermarkets could offer customers a variable pricing system based on the product’s expiration date (Rebedea and Florea 2020). Innovation technologies for food waste management could also be adopted, such as using food waste as a protein source for black soldier fly farming for pet food sources (Hopkins et al. 2021). Lowering storage temperatures in supermarkets for some products (e.g., dairy, cheese, delicatessen, and meat products) was a viable approach for reducing food waste, since it helped to extend product shelf life; however, it was not an efficient method to reduce GHG emissions, as it required more electricity (Eriksson et al. 2016). Installing solar roof panels on car parking lots could produce about 445 kW h and potentially reduce 406 t CO2 emissions yr−1 of GHGs emitted from the energy used by tenants. By using an inverter air conditioner, energy use was reduced, with the potential for a 44% reduction of total GHG emissions, which was similar to the findings by Almogbel et al. (2020).
5. Conclusions
Reducing greenhouse gas emissions from organizations’ direct activities and from the indirect activity of purchased electricity production has always been a focus; however, there are significant additional GHG emissions from all indirect activities that occur along the whole value chain of the service sector. The current study demonstrated that scope 3 GHG emissions amounted to 94% (33 784 t CO2 emissions yr−1) of total GHG emissions from scopes 1 and 2, which was a substantial contribution that should not be overlooked in GHG management. Categories that should be included in the scope-3 GHG emission activities of the organization, following the requirements of ISO 14064:2021, should include at least the following: (i) purchased goods and services, (ii) fuel- and energy-related activities, (iii) waste generated in operations, (iv) business travel, (v) downstream transportation and distribution, (vi) use of sold products, and (vii) end-of-life treatment of sold products. The key contributors to GHG emissions associated with scope-3 activities were as follows: (i) purchased goods and (ii) food waste from expired goods. More efficient GHG mitigation measures and GHG management strategies were suggested to reduce the scope-3 GHG emissions. Purchased products and services carrying a carbon-reduction label should be given priority, which would also raise customer awareness of their informed purchasing to reduce climate impacts. Supermarket retail operations could inform their network suppliers of this, to encourage more manufacturers to apply for a carbon-reduction label. Such a marketing mechanism would help to accelerate GHG reductions in both production and consumption. The application of AI and innovation could be implemented to reduce the amount of food waste from expired goods, which would also contribute to the GHG reduction associated with all inputs used in producing, processing, transporting, preparing, and storing those foods. This information could be useful as guidance for supermarket retailers to take into account those GHG emission sources attached to value chain activities and to identify potential GHG reduction strategies. These inputs would certainly support not only target reduction targets for the supermarket retailers but also achievement of the national and international climate goals on carbon neutrality and net-zero emissions.
Acknowledgments.
The Thailand Greenhouse Gas Management Organization provided financial support. A local supermarket retailer generously supported data collection. No potential conflicts of interest were reported by the authors.
Data availability statement.
The data that support the findings of this study are available from the corresponding author upon request. The data are not publicly available because they contain information that could compromise the privacy of research participants.
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