How Airports Generate Power and Manage Energy

A modern international airport is a small city in terms of energy demand. The terminal buildings must be heated, cooled, and lit 24 hours a day. Runway and taxiway lighting systems consume megawatts of power. Baggage handling systems, escalators, elevators, people movers, IT networks, security equipment, and thousands of retail and food outlets all draw electricity. A large hub airport like London Heathrow (LHR) consumes roughly the same amount of energy as a city of 50,000 people. How airports generate, procure, and manage this energy has become one of the most consequential questions in the industry's pursuit of sustainability.

The Scale of Airport Energy Consumption

Airport energy consumption varies enormously depending on size, climate, and operational characteristics. A small regional airport might consume 2 to 5 GWh (gigawatt-hours) of electricity per year. A major international hub consumes 200 to 500 GWh — comparable to a medium-sized manufacturing plant. Atlanta Hartsfield-Jackson (ATL), the world's busiest airport by passenger numbers, consumes approximately 350 GWh of electricity annually. Dubai International (DXB), located in a hot desert climate requiring year-round air conditioning, has even higher per-passenger energy intensity.

The largest single energy load at most airports is HVAC (heating, ventilation, and air conditioning), which typically accounts for 40% to 60% of total electricity consumption. Terminal buildings present a particular challenge because they are simultaneously very large (millions of square meters), very tall (high ceilings required for operational and aesthetic reasons), and frequently open to the outside (doors opening constantly as passengers, vehicles, and goods move through). Maintaining comfortable temperatures in this environment requires enormous cooling or heating capacity.

Lighting is the second-largest load, accounting for 15% to 25% of electricity consumption. This includes terminal interior lighting, parking garage lighting, and — critically — airfield lighting. Runway edge lights, approach lights, taxiway centerline lights, and PAPI (Precision Approach Path Indicator) systems must operate reliably under all weather conditions, and the total airfield lighting load at a large airport can exceed 10 MW.

On-Site Power Generation

Many airports operate their own power generation facilities to supplement or replace grid electricity. The most common technology is combined heat and power (CHP), also called cogeneration, which generates electricity from natural gas turbines and captures the waste heat for building heating and cooling. A CHP plant typically achieves 70% to 85% overall energy efficiency, compared to roughly 35% to 45% for a conventional power plant that discards its waste heat. JFK Airport (JFK) operates a large cogeneration plant that supplies both electricity and steam heating to the terminal buildings.

Solar photovoltaic (PV) installations have become increasingly common at airports. Airports offer several advantages as solar sites: they have large areas of flat roof space on terminals, hangars, and parking structures, and they control large land areas that can host ground-mounted solar arrays. Cochin International Airport (COK) in India became the world's first fully solar-powered airport in 2015, generating more electricity from its 46,000-panel solar installation than it consumes. Since then, dozens of airports have installed large-scale solar systems.

Delhi Indira Gandhi International (DEL), one of the world's busiest airports, operates a 7.84 MW solar installation on rooftops and ground areas. Denver International (DEN) has a 4.4 MW solar array on airport land. In Australia, Adelaide Airport (ADL) operates a solar farm that generates a significant portion of the airport's electricity. The economics of airport solar have improved dramatically as panel costs have fallen, and new airports designed in the 2020s routinely incorporate solar generation as a standard infrastructure element rather than an optional add-on.

Ground Power and Pre-Conditioned Air

One of the most significant energy-related decisions at an airport is whether parked aircraft use their own auxiliary power units (APUs) — small jet engines in the aircraft's tail that generate electricity and pressurized air for the cabin systems — or are supplied with electricity and air conditioning from airport-provided ground equipment. APUs burn jet fuel, generate noise, and produce emissions. Fixed electrical ground power (FEGP) units and pre-conditioned air (PCA) units at gates are powered by the airport's electrical grid and are far cleaner and quieter.

Most major airports now mandate or strongly encourage the use of FEGP and PCA instead of APUs. Stockholm Arlanda (ARN) in Sweden was one of the first airports to ban APU use at gates, requiring all parked aircraft to use ground power. The savings are significant: a single wide-body aircraft APU burns approximately 200 liters of jet fuel per hour. Across an airport with 200 gate stands, the cumulative fuel savings — and corresponding emission reductions — from mandating ground power are substantial.

Energy Efficiency Measures

The most cost-effective approach to airport energy management is reducing consumption through efficiency measures. The LED revolution has been particularly impactful: replacing conventional lighting with LED fixtures throughout terminals, parking garages, and airfield lighting systems can reduce lighting energy consumption by 50% to 70%. Los Angeles International (LAX) completed a comprehensive LED retrofit that reduced lighting energy consumption by approximately 60% and significantly reduced maintenance costs (LED fixtures last 5 to 10 times longer than conventional lamps).

Building management systems (BMS) use sensors and algorithms to optimize HVAC operation in real time. Rather than maintaining a constant temperature throughout the terminal, a modern BMS adjusts heating and cooling zone by zone based on occupancy, solar heat gain, and outdoor conditions. Some airports have installed thermal storage systems that produce chilled water during off-peak hours (when electricity is cheaper) and use it for cooling during peak demand periods.

Airfield lighting control systems can dim runway and taxiway lights when they are not in use or when visibility conditions permit lower intensity. Advanced LED airfield lighting allows stepless dimming, which was impossible with older incandescent fixtures. Frankfurt Airport (FRA) has implemented an intelligent airfield lighting system that adjusts intensity based on weather conditions and ATC requirements, reducing energy consumption while maintaining safety.

The Path to Net-Zero Airports

The Airport Carbon Accreditation (ACA) program, managed by Airports Council International (ACI), provides a framework for airports to measure, reduce, and offset their carbon emissions. The program has six levels: Mapping, Reduction, Optimization, Neutrality, Transformation, and Transition. As of 2024, over 500 airports worldwide participate, and more than 90 have achieved Level 4+ (Neutrality or above), meaning they have reduced their Scope 1 and 2 emissions to the maximum extent feasible and offset the remainder.

London Heathrow (LHR) has committed to net-zero operational carbon by 2030. Amsterdam Schiphol (AMS) has set a similar target. San Francisco International (SFO) sources 100% of its electricity from renewable energy (purchased via power purchase agreements) and has achieved carbon-neutral status for its Scope 1 and 2 emissions.

The distinction between Scope 1, 2, and 3 emissions is critical for understanding airport net-zero claims. Scope 1 covers direct emissions from airport-owned sources (vehicles, heating systems). Scope 2 covers indirect emissions from purchased electricity. Scope 3 covers emissions from sources the airport does not own or control — including aircraft operations, passenger ground transport, and tenant energy use. Aircraft operations typically account for over 95% of an airport's total carbon footprint. Most airport net-zero commitments address only Scopes 1 and 2, leaving the much larger Scope 3 emissions (primarily from aircraft) outside the airport's direct responsibility.

Hydrogen and Future Energy Systems

Hydrogen is attracting significant attention as a potential future energy source for both airport operations and aircraft propulsion. Green hydrogen — produced by electrolyzing water using renewable electricity — could power ground vehicles, provide building heating, and eventually fuel hydrogen-powered aircraft. Heathrow has commissioned studies on hydrogen infrastructure, and Paris CDG is planning a hydrogen hub that could supply both ground vehicles and, eventually, hydrogen-fueled aircraft.

The timeline for hydrogen in aviation is measured in decades rather than years. Airbus has committed to developing a hydrogen-powered commercial aircraft (the ZEROe concept) by 2035, but the airport infrastructure required to store, distribute, and fuel hydrogen at scale does not yet exist. Building that infrastructure — hydrogen production facilities, storage tanks, distribution pipelines, and aircraft fueling equipment — represents a multi-billion-dollar investment that airports and energy companies are only beginning to plan.

In the nearer term, battery storage is emerging as an important tool for airport energy management. Large-scale battery systems can store solar-generated electricity for use after dark, absorb peak demand spikes that would otherwise require additional grid capacity, and provide backup power during grid outages. As battery costs continue to fall, more airports are incorporating storage into their energy strategies — a trend that is likely to accelerate as both solar generation capacity and the demand for electric ground vehicle charging increase.