Airlines and airports receive a lot of unwanted attention in relation to the emissions produced by the aircraft that are otherwise such a welcome feature of the modern world. Both carriers and airline operators are looking to minimise harmful emissions however they can, and it is not just aircraft to which they have turned their attention
As well as aircraft, other ‘contributors’ to the global aviation industry’s emissions are the GSE used to handle and service those airplanes. Not surprisingly then, many airport operators have been keen to encourage the operators of GSE on their ramps to switch to equipment that keeps down their gateways’ carbon footprint.
Amongst the airports that have taken the lead on this have been those located in the Scandinavian countries, which more generally have been at the forefront of the effort to minimise harmful emissions and slow the process of global warming.
Swedavia, Sweden’s national airport operator, is wholly owned by the Swedish state. It owns 10 airports, including the nation’s biggest and busiest, Stockholm ArlandaIts mission includes the aim of being an “international role model in sustainability”.
As part of this goal, it has committed itself to being a “world leader in developing airports with the least possible climate impact”. Swedavia’s objective is to produce zero fossil carbon dioxide emissions from its own operations by 2020.
That target was adopted on 2011 and is expected to be achieved next year – as planned – at the latest.
Swedavia is also contributing to fossil-free air transport by taking a driving role in the industry’s shift to bio fuel, with the goal of achieving fossil-free Swedish air transport by 2045.
Meanwhile, in terms of the process of moving to greener GSE within a wider environmental strategy, Anders Östlings, head of airside and landside operations at Stockholm Arlanda Airport, recalls: “During the first few years, our activities were focused on green electricity, comfort control in buildings and the shift to LED lighting. Once the big measures were identified and launched in those areas, the focus was on motor vehicles, equipment and fuel.
“Investments in vehicles and equipment have been carried out so that they run on a combination of electricity, biogas and fossil-free diesel. The size of the vehicle/equipment and the way it is used together with what the market has to offer, has determined what choices were made.”
The process has involved working closely with ground service providers/handlers and finding ways of incentivising them to use greener technologies. “Swedavia’s target is focused on its own operations,” says Östlings. This means that, for the regional airports, where Swedavia itself carries out ground handling, the target applies directly to its own operations.
However: “For the larger airports, where Swedavia does not carry out ground handling operations, steps have nonetheless been taken in the same direction. These include, for Stockholm Arlanda Airport, a definition of ‘environmental car’ has been introduced.
“Furthermore, Swedavia also offers fossil-free fuel to external ground handling companies. The next step at Arlanda is for Swedavia to take increased responsibility for ground handling equipment and, as a result, we will also be able to directly influence the choice of products.”
Swedavia has taken big steps in the process of minimising the environmental impact of its gateways. “As a result of the strategy Swedavia has followed and the targets that have been adopted, all of Swedavia’s airports are accredited at the highest level under ACA [Airport Carbon Accreditation] standards,” says Östlings.
“Three of our airports have also achieved the target of zero fossil carbon dioxide emissions. Although many people thought the target set in 2011 was bold and were doubtful that it would be achieved, now everyone is convinced that we really will do this in 2020.”
But more remains to be done, of course. “The next step in minimising the environmental impact from Swedavia’s airports is the aim to get airlines to use fossil-free fuel,” says Östlings.
“Many people also consider this to be a bold target, but Swedavia is firmly determined that we will also succeed in this effort. This in turn would be a step closer to reaching the goal of having a fossil-free domestic aviation [industry] in Sweden by 2030.”
Other European gateways are working hard alongside their GSE operators to minimise emissions. Germany’s Stuttgart Airport is another that has taken a lead on this. In fact, the authority responsible for the German airport, Flughafen Stuttgart, intends to halve its greenhouse emissions by 2030 as compared to 1990 and to be completely carbon-neutral by 2050.
It has already made a very good start down this road, with all of its 16 passenger buses and all of its 24 baggage tugs now being electrically powered, as are many of the other GSE units (including belt loaders and high loaders) operating on its ramp.
The process of electrifying all GSE on the Stuttgart Airport ramp – another stated objective – was launched from a foundation called the efleet programme that dates back more than six years.
The efleet programme involved a collaboration of the airport authority with the German Government (specifically, the German Federal Ministry for Economic Affairs) and other agencies, including the German Aerospace Center (the DLR) and relevant GSE manufacturers like Schopf, Cobus and MULAG. Launched in 2012, it entailed testing and analysing equipment with a view to assessing how best to switch to electrically powered ramp equipment.
The project assessed such concerns as the potential energy saving and emission minimisation that could be achieved through GSE electrification, what size and type of batteries might best be adopted and much more besides, recalls Martin Hofmann, GSE fleet manager at Flughafen Stuttgart.
For Stuttgart Airport, the first of its tasks was to assess which of its equipment types were the biggest consumers of fuel (and so creators of harmful emissions) on its ramp, and to move quickly to replace those with electric GSE. The three main fuel guzzlers were found to be passenger buses, baggage tractors and ground power units (GPUs).
Once that was ascertained, the airport authority moved quickly towards a fully electric fleet of Cobus apron buses and electric baggage tugs. It has also now begun switching from mobile diesel-powered GPUs providing on-stand power to static, underground provision of electric power – 14 stands have already been so equipped, with 14 more expected to have underground power supply by 2022.
Other GSE types are also being addressed in this search for full apron equipment electrification. For example, the last of the airport’s belt loaders are being converted to green power, while electric passenger stairs are starting to be introduced. And Flughafen Stuttgart’s car fleet is also being converted to electric power, with the required alternating current (AC) charging points being installed.
The gateway hosts two ground handlers: a subsidiary of the airport operator itself called Stuttgart Airport Ground Handling (SAG) and private sector licence holder Losch Airport Service. Both handlers have worked closely together to make the conversion to electric GSE a reality, says Hofmann. “Losch has been fully on board with this process, and we have shared our data and our experience with them,” he adds.
The two handlers are collaborating rather than competing on this process, both keen to reap the rewards of the synergies that can be gained from moving across to shared electric infrastructure. The project of collaboration with Losch on electrification forms part of the gateway’s ‘Scale up!’ sustainability project that continues to enjoy the spport of the German Federal Government – all within the overarching Flughafen Stuttgart strategy of ‘fairport STR’: to be one of the “best-performing and most sustainable airports in Europe”.
Results shared with Losch are also shared with other German airports when, and with other handlers and GSE manufacturers as part of the wider process of sponsoring the introduction of greener GSE and greater environmental sustainability across German airports.
Moreover, Stuttgart has acted as a sort of ‘demonstrator airport’ to foreign air gateways when it comes to GSE electrification, especially as regards electric bus transport on the apron. Numerous airport operators from beyond Germany’s borders have come to see the benefits of having a fully electric Cobus fleet, for example.
Changi sets its priorities
Away from Europe, airports in other parts of the world are equally conscious of their environmental responsibilities, and are working hard to minimise the harmful effects of GSE emissions. In the Far East, nations such as Singapore and Hong Kong are setting the standards, but there are also initiatives under way in places that might seem less likely to be focusing on this issue, including China.
Singapore’s Changi International Airport is operated by Changi Airport Group (CAG). It has been working with its ground handling partners to reduce carbon emissions and one tangible outcome has been a partnership to convert diesel-powered baggage tractors to electric baggage tractors.
CAG has installed 26 common-use charging points to encourage the adoption of electric baggage tractors, so that Changi’s ground handlers do not need to install their own chargers. The common-use approach minimises duplication of resources and reduces the cost and space required for charging infrastructure.
Today, there are over 80 electric baggage tractors operating in the airside environment at Changi. Baggage tractors at many airports worldwide are, of course, more traditionally powered by conventional diesel engines and thus emit fumes which can be an occupational health hazard for baggage handling staff working to transport bags between the aircraft and terminal buildings.
With the support of its ground service providers, CAG has promoted the use of clean-energy baggage tractors within the airport’s baggage handling areas, starting with Terminal 4 (T4) in November 2017.
According to a CAG spokesperson: “As a result, we have received positive feedback from our baggage handling community on the improvement in the work environment. Since we embarked on this journey, we have saved over 1,000 tonnes of carbon dioxide emissions.”
She continues: “With the success of this initiative, CAG is progressively installing additional electric vehicle chargers throughout the airside areas of Terminals 1, 2 and 3.
“Beyond baggage tractors, our goal is to progressively convert the majority of vehicles and mobile equipment that operate airside to be electric-powered. This year, CAG has led efforts to install an additional 88 charging points across Terminals 1,2 and 3. This will significantly mitigate greenhouse gas emissions airside as well as enhance the working environment for our airport community.”
ITW GSE takes the lead
ITW GSE is one of the many GSE manufacturers that have looked to supply the growing demand for greener GSE. A division of Illinois Tool Works, ITW GSE supplies a wide range of ground power units (GPUs), pre-conditioned air units (PCAs) and related cables and hoses (prior to April 2018, this GSE was variously sold under the AXA Power, Hobart, Houchin and J&B Aviation brands) and it has long since looked to meet the needs of airports wanting to go ‘cleaner and greener’.
Its latest efforts in this regard relate to the ITW GSE 7400 battery-powered GPU (or eGPU). The company recently calculated that by replacing just one Tier III diesel GPU with a battery-powered GPU, a reduction in carbon dioxide emissions equal to those of 49 average cars could be achieved. “Think how this would contribute to a greener environment at an airport where they may have 50-100 old diesel units,” ITW GSE asks.
The company’s vice president sales and marketing, Poul Elvstroem, notes: “We can clearly see that airports all over the world are taking on responsibility [for the environment]. Many airports have well-defined climate strategies and, today, almost half of global passenger traffic passes through Airport Carbon Accredited-airports and the number of these airports is rapidly increasing.
“More and more airports are interested in reducing their environmental impact because there is prestige related to going green or because they experience pressure from outside.”
Since the eGPU reduces CO2 by 90% and NOx emissions by 95%, it is a great opportunity for airports to reduce their carbon footprint on remote stands and in hangars as well.”
ITW GSE has manufactured both diesel and solid-state GPUs and pre-conditioned air (PCA) units for many years. “As ITW GSE’s vision is to supply the aviation industry with the cleanest, most reliable and cost-efficient GSE systems and bearing in mind the focus on environmental issues, it was a natural choice when we decided to concentrate our R&D efforts solely on our green product portfolio back in 2018,” Elvstroem informs.
“Beside our green, solid-state core products that don’t emit any exhaust fumes or NOx particles at the place of use, our portfolio also includes the battery-driven eGPU. After a conceptual model was launched at inter airport 2017, the 7400 GPU has recently been developed in an updated version. To fulfil customer requirements, the 7400 unit will also come in a hybrid version towards end of 2019 and a 28 VDC pack that can be used alone or in combination with the 400Hz eGPU will also be developed.”
ITW GSE has its own research to back up its belief in the importance of cleaner GPUs. A 2012 study undertaken by Copenhagen Airport shows that air pollution on the ramp, on average, is double that of rush-hour traffic in the city centre, Elvstroem says. Of the many sources of this pollution, the biggest are diesel-powered GPUs that emit nine times the level of harmful ultra-fine particles found in the air on the busy street.
“At ITW, we have analysed the number of GSE units and the emissions from each of those during an aircraft turnaround. Although people are tempted to think that pushback tractors would be the biggest sinner in this respect, our investigations show that 42% of emissions come from a diesel-driven GPU, because the diesel unit is running all the time whereas other types of equipment are not.”
So, for an airport that wants to go green, the replacement of diesel GPUs by eGPUs clearly gives the most ‘green’ value for money, Elvstroem considers.
Today, the ITW GSE 7400 battery-powered GPU is in use at airports ranging from Amsterdam Schiphol and Frankfurt to Brisbane and Los Angeles. Plus, the unit is on trial at airports including Sharjah in the UAE, Eindhoven in the Netherlands, Helsinki in Finland, Zurich in Switzerland, Madrid and Barcelona in Spain, and Rome in Italy.