At a time when there is growing concern about the carbon footprint of global aviation, countries like Nepal that depend on tourism have started to think about how to reduce their emissions.

Not much can be done about the use of aviation fuel except to make engines and aircraft more fuel-efficient, or to switch to sustainable aviation fuels (SAF). But these technologies have their limits, so airlines have started concentrating on the non-flying ground activities and switching them to renewable energy.

Reducing congestion at airports like Kathmandu which require planes to hold for long periods in the air to land, or in the taxiway to take off, would reduce fuel burn. Ramp buses, towing tractors, crew transport and hangar equipment, for example can be battery operated, or switched to solar energy.

With the runway and taxiway upgrades at Kathmandu airport which will be completed by 1 April is expected to reduce congestion, some domestic airlines in Nepal have started using electric buses and ground transport to reduce emissions. Since 100% of Nepal’s grid electricity is hydropower or solar energy, it also means a reduction in the country’s petroleum import bill.

According to the International Air Transport Association (IATA), aviation accounts for up to 4% of global warming, and CO? emissions from civilian aircraft worldwide more than doubled between 1990 and 2020. The airline industry also emits other greenhouse gases like methane, nitrous oxide and NOx. Military aircraft are not included in these figures and are even more polluting.

Other ways to reduce aviation emissions is to shorten flight paths with new GPS-based technologies, and invest in carbon offsets outside the aviation sector. IATA and ICAO members have agreed to achieve net zero by 2050.

In Nepal, where domestic aviation plays a major role in connectivity, efforts toward greener alternatives have gained momentum in the past few years. Buddha Air, Nepal’s leading domestic airline, has taken a significant step toward sustainable aviation by introducing electric Ground Power Units (e-GPUs), reducing reliance on diesel-powered systems.

GPUs provide electrical power to aircraft while they are parked at the airport before the engines start, to run primary aircraft functions such as lighting, avionics, air conditioning, hydraulics, and pneumatics after engines are shut down.

Traditionally, diesel-powered GPUs have been the standard in Nepal, but they come with major challenges, including air and noise pollution, high fuel costs, and logistical difficulties.

“When an aircraft is on the ground, the system providing power is the Ground Power Unit,” explains Diwakar Shrestha, GSE In-Charge of Buddha Air. After landing, once both engines are shut down, the aircraft still needs power, and the GPU supplies it. “Traditionally, our GPUs were powered by diesel and at Kathmandu airport alone they consumed 18,000 litres of diesel monthly.”

The transition from diesel to electric GPUs is a milestone in Nepal’s aviation sustainability efforts. Shrestha highlights the challenges faced during the shift, stating, “When we initiated discussions to eliminate diesel dependency, it was a big challenge”. The team had to undertake a complete transition from diesel to electricity. “But by gathering resources, and utilising Nepali technologies and local expertise, we successfully implemented the electric GPU system.”

Kaushal Bhandari, Station Manager of Buddha Air in Biratnagar notes, “Diesel-powered GPUs used to generate excessive noise, hindering communication among staff. Now, our operations have become much more efficient, free from noise pollution and diesel smoke.”

The Civil Aviation Authority of Nepal (CAAN) has played a central role in expanding this technology across the country. Subhash Jha, Airport Chief at Biratnagar states, “When Buddha Air proposed phasing out diesel GPUs, CAAN took the initiative to support this transition by providing a dedicated transformer for electric GPUs, enabling the implementation of this technology at seven domestic airports in Nepal.”

Seven airports in Nepal already use electric GPUs, and there are plans for expansion to other airports, as well as converting other ground-handling equipment to battery power.

Source: Nepali Times