Airport Greenhouse Gas Emissions Inventory: A Primer (2024)
Chapter: 6. Implement Emission Reduction Strategies
6. Implement Emission Reduction Strategies
Airports worldwide are increasingly committed to reducing their carbon footprints and adopting more sustainable practices. This section highlights the potential steps and resources available to establish effective and customized emission reduction strategies for your airport. By addressing the challenges head-on and embracing the opportunities and best practices from sustainable aviation, airport operators can align themselves with international climate goals and future-proof their business in an evolving industry. This section presents an approach for developing and implementing emission reduction strategies organized into four steps: 1) Identify, 2) Evaluate, 3) Prioritize, and 4) Implement.
6.1 Identify
The first step in reducing an airport’s emissions is identifying the potential strategies the airport operator can implement. Previous studies on emission reduction strategies have identified 12 major categories:
- Airfield Design and Operations
- Business Planning
- Construction
- Carbon Sequestration
- Energy Management
- Ground Service Equipment
- Ground Transportation
- Materials and Embedded Energy
- Operations and Maintenance
- Performance Measurement
- Renewable Energy (on-site)
- Refrigerants
ACRP Report 56: Handbook for Considering Practical Greenhouse Gas Emission Reduction Strategies for Airports includes fact sheets that airport operators can use to identify strategies within these categories. As an example, under the Energy Management emission reduction strategy category, an airport located in a part of the U.S. that receives a significant amount of sunlight might identify the strategy of installing window awnings and sunshades in airport facilities to reduce the amount of energy spent on air conditioning to cool the airport as a promising energy reduction, and therefore emission reduction, strategy.
6.2 Evaluate
Evaluating GHG reduction opportunities is the next step for airport operators to develop implementable strategies to mitigate emissions. By assessing the impact of emission reduction strategies against an airport’s unique circumstances, including its resources, geographies, and priorities, airport operators can gain insight into a strategy’s feasibility, cost-efficiency, and contribution towards achieving emission reduction targets. A thorough evaluation also ensures accountability and transparency in the climate action planning process.
Evaluation Criteria
Airport operators should consider the following evaluation criteria when assessing whether a specific emission reduction strategy is appropriate for their airport. The evaluation criteria are organized into three categories:
Financial Considerations:
- Estimated capital costs
- Estimated operation and maintenance costs
- Estimated payback period
Implementation Considerations:
- Implementation timeframe
- Maturity of the reduction strategy
- Airport control
Potential Impacts:
- GHG reduction potential (Scopes 1 and 2)
- GHG reduction potential (Scope 3)
- Impacts to natural resources
- Impacts to the built environment
- Impacts to regulatory compliance
Following the example of installing window awnings and sunshades to improve energy management, an airport operator may evaluate the emission reduction strategy and find that window awnings and sunshades are relatively low cost to purchase and install, can be installed by the airport on a short timeline, and have the potential to significantly reduce electricity consumption, and therefore Scope 2 emissions, from the airport. Based on the evaluation criteria, the airport operator may decide that installing window awnings and sunshades is an effective strategy for achieving the airport’s emission reduction goals.
Other evaluation criteria can include considerations toward risk management, technology and innovation, community or corporate partnerships, and the airline passengers, employees, and businesses an airport engages with daily.
There are resources available to assist with evaluating emission reduction measures. As an example, AirportGEAR (Airport Greenhouse Gas Emission Assessment and Reduction) is a decision-support tool designed to assist airport operators with evaluating emission reduction strategies.
Considering Environmental Justice in Emission Reduction Strategies
GHG inventories play a crucial role in shaping a comprehensive strategic framework for reducing GHG emissions. While GHG emission reduction actions can potentially yield unintended negative consequences, they also present opportunities for co-benefits that amplify the social benefits of these efforts, such as improved air quality.
Airports are often located in low-income disadvantaged communities (LiDAC). As a result, these communities face the unequal burden of localized environmental impacts from airport operations, such as poor air quality, potential damage to local wildlife and habitats, and noise pollution. Therefore, environmental justice (EJ) considerations should be applied throughout the development of GHG reduction goals and actions. Incorporating EJ helps to minimize unintended negative consequences and unlocks the potential for realizing and equitably distributing greater co-benefits from GHG reduction goals.
For example, some airports purchase carbon offsets—a credit that represents projects with GHG mitigation benefits elsewhere for institutions to claim toward their own GHG reduction goals. Some carbon offsets—particularly for projects located in developing countries—specifically consider community benefits and impacts in their price structure. Airports may wish to consider the benefits and tradeoffs associated with pursuing these emission reduction strategies generally, and in relationship to environmental impacts experienced by communities that surround the airport.
6.3 Prioritize
The third step for airport operators is to prioritize the identified emission reduction strategies based on their evaluations of the strategies’ effectiveness for achieving the airport’s emission reduction goals. Prioritization allows an airport operator to best allocate resources and time, ensuring that the most critical or effective reduction strategies are in line to be implemented first. While the specific emission reduction strategies applied by each airport will be different depending on its unique circumstances, the following general framework can be used to prioritize emission reduction strategies:
- Avoid Emissions: Strategies that improve resource and energy efficiency, thereby avoiding emissions, should be prioritized first because they are often the most cost-effective option for achieving emission reduction goals and within the airport operators’ direct control. Emissions avoidance strategies tend to be low cost, rely on readily available technology, and result in lowered energy use over time. Some example strategies to avoid emissions include replacing lighting fixtures, installing temperature controls, and minimizing leaks in heating, ventilation, and air conditioning systems.
- Employ Low Carbon Solutions: Strategies to adopt low carbon solutions should be prioritized next. Such strategies may include the decarbonization of airport operations through electrification, such as through procuring electric pre-conditioned air (PCA) units, purchasing renewable energy certificates, switching to low-carbon fuels to power airport-owned equipment, and procuring or generating on-site renewable electricity.
- Sequester Unabated Emissions: The lowest priority emission reduction strategies should sequester residual emissions that could not be abated by other means. Emissions sequestration strategies may involve carbon capture and storage to remove carbon dioxide from the atmosphere or purchasing carbon offsets.
The window awnings and sunshades example emission reductions strategy qualifies as a strategy to avoid emissions whose implementation should be prioritized over other emission reduction strategies such as low carbon strategies and sequestering unabated emissions.
6.4 Implement
The next step is to implement the prioritized emission reduction strategies. Implementation involves a systematic and comprehensive approach as well as engagement, financial resources, and long-term performance tracking.
An important consideration for implementation is commitment. An airport operator should engage its leadership team first to secure support from upper management and its decision-makers. Additionally, those responsible for implementation should engage other stakeholders, such as its employees, tenants, local communities, local regulatory bodies, and environmental organizations to foster collaboration and create a shared commitment to sustainability.
Financing is another important consideration for an airport operator when implementing emission reduction strategies. Financing requires a strategic approach to balance the high upfront costs of implementation with the long-term financial benefits of efficiency. With the upfront costs and return on investment of a strategy pre-determined during the evaluation and prioritization steps, an airport operator can begin to seek out funding from both internal and external sources. Examples of an internal source may be an airport’s operational or facility management budget or profits from the participation in a carbon market.
Examples of External Funding Sources for Airport Emission Reduction Programs
Voluntary Airport Low Emissions Program (VALE)
Since 2004, VALE has provided grants for airports to help meet state-related air quality requirements through airport improvements, such as through procuring low emission vehicles and electric PCA units.
Airport Zero Emissions Vehicle (ZEV) and Infrastructure Pilot Program
Since 2012, the ZEV and Infrastructure Pilot Program has allowed airports to use Airport Improvement Program grants to purchase zero-emissions airport vehicles and the infrastructure to operate them, such as charging stations.
Example external funding sources may include government grants, loans, or subsidies specifically designed to support sustainability projects, utility company rebates, or partnerships with private-sector companies willing to invest in GHG reduction initiatives.
Lastly, monitoring and reporting are crucial to a successful implementation. For each emission reduction strategy, a monitoring and reporting system should also be developed to track implementation progress, emission reduction progress, and financial progress to understand both the timeline and success of implementation of the reduction strategy. This data should be collected and reported to the appropriate stakeholders, including airport leadership, to allow for transparency and accountability
Sustainable Aviation Fuel
A common first step for airports as they prioritize emission reduction strategies is to focus on emissions within the airport’s control (Scope 1 emissions); however, airports are also evaluating broader opportunities for emission reduction through use of sustainable aviation fuel (SAF).
Airports can influence and support GHG reduction measures that relate to their Scope 3 emissions, including aircraft LTO emissions. Based on the studies conducted and cited in ACRP 100: Carbon Removal and Reduction to Support Airport Net-Zero Goals a focal point to reduce airline emissions is addressing aviation fuel consumption; wherein, airports play an important role in supporting the long-term benefits of transitioning aircrafts to sustainable aviation fuels and aggregating demand for SAF.
A fueling infrastructure study is the best first step for airport operators that wish to facilitate SAF adoption at their airport. It is important to note that SAF programs can become complex, multiyear efforts as airports solve questions around the delivery and development of SAF and their role in helping build a stronger SAF market. Refer to the best practices and lessons learned by large-hub airports currently using SAF such as Seattle-Tacoma International Airport (SEA), Los Angeles International Airport (LAX), and San Fransisco International Airport (SFO) and work directly with stakeholders (airlines, industry experts, regional stakeholders, etc.) to address challenges.
and to promote the success of the emission reduction strategy. Monitoring and reporting on progress also allows for an airport to regularly review its processes for implementation, identify inefficiencies, and update its process to adapt to changing circumstances, technologies, and goals.
Finishing with the example of the window awnings and sunshades in the implementation phase, the airport operator may secure support from upper management based on the evaluation results of the emission reduction strategy indicating this action will help the airport achieve its emission reduction goals. The airport operator may then find internal funding for the project in the airport’s facilities management budget. After window awnings and sunshades are installed, the airport operator’s GHG accounting team should note in their annual GHG inventory when the window awnings and sunshades were installed so that they can monitor the effectiveness of the strategy for reducing electricity use, and therefore Scope 2 emissions.
