Government of Canada navigation bar

Symbol of the Government of Canada

Primary site navigation bar

Breadcrumb

Aircraft Ground Power Units

Project Overview : This demonstration project field tested the use of ground power units to reduce aircraft engine use, fuel consumption and greenhouse gas (GHG) emissions.

Organization: Northern Thunderbird Air Inc.              

Project Timeline:  January 1 to June 30, 2010

Project Results: The acquisition of five ground power units resulted in reduced consumption of aircraft fuel and related emissions. More information on both the performance and financial results are available in the Detailed Project Results section of this case study.

     Summary of Results
Annual Fuel Reduction Annual GHG reduction Annual Energy Cost Savings Capital Cost of Equipment (including taxes) Payback period
62,460 L 158.8 T $ 56,981 $56,625 13 months

Project Description

Northern Thunderbird Air Inc. is a regional airline based in Prince George, BC, providing scheduled and chartered flights to northern BC and the Yukon. The company operates a fleet of Beechcraft and Cessna aircraft.

The company purchased and installed five Hobart GPU-600, 28.5 volt DC ground power units (GPUs) to show that they could reduce fuel use and GHG emissions. The GPUs are used to supply power to parked aircraft while the engines are shut down, saving fuel and associated emissions, and to conduct instrument testing without needing to start engines. The GPUs are also used to reduce engine use during maintenance testing conducted indoors. This not only decreases the amount of aircraft fuel used, but reduces the need to open hangar doors to vent exhaust.

Methodology

Northern Thunderbird Air tracked the jet fuel savings from using the GPUs to reduce start times as the aircraft prepare for departure for the first six months of 2010. The reduction in jet fuel consumption was calculated using the average cost per start considering time and fuel savings. 

It was intended to track the savings in space heating costs, due to using GPUs to conduct instrument checks on aircraft while they were in the Prince George hangar, by reducing the need to open doors to vent exhaust. The hangar and records were lost to fire during the study and it was not possible to calculate space heat cost savings.

Detailed Project Results

The GPUs reduce aircraft fuel use in three ways. First, they are used to reduce the time aircraft engines need to run prior to takeoff. It was calculated that a GPU reduces fuel use by 10.8 L per start. Second, GPUs reduce engine time and fuel required to perform maintenance checks, particularly in Vancouver where strict noise abatement policies require that aircraft be taxied to a specified area of the airport for any testing. Third, the GPUs allow certain maintenance activities conducted indoors to be done without the engines running. (This also reduces space heating costs but this could not be quantified during the study.)

A) Performance

     Table 1 - Performance
  Aircraft Starts Maintenance Checks
Location Number Fuel savings1
Litres 		GHG saving
tonnes CO2e 		Number Fuel savings2
Litres 		GHG saving
tonnes CO2e
Edmonton 52 561.6 1.4 - - -
Vancouver 636 6868.8 17.9 110 7925.5 20.6
Prince George 867 9363.6 24.3 80 2162.2 5.6
Calgary 57 615.6 1.6  -  -  -
Smithers 338 3650.4 9.5  -  -  -
Total for 6-month test period 1,950 21,060.0 54.7 190 10,087.8 26.2
Fuel Savings Study period (6 months) 21,060+10,088 = 31,148 L
Projected annual 2 (31,148) =  62,296 L
GHG Reduction Study period (6 months) 54.7 + 26.2 = 80.9 tonnes
Projected annual 2 (80.9) = 161.8 T

1. Based on Beech 1900 idle fuel usage of 200 lbs per hour (approx. 121 L per hour).

2. Based on 40 minutes or 72.1 litres per start for Vancouver and 15 minutes or 27.0 litres per start for Prince George.

B) Financial Results

The payback period for the ground power units was estimated to be 13 months.

     Table 2 - Fuel Savings and Payback
Annual Fuel Reduction Annual Energy Cost Savings1 GPU Cost Payback period
62,296 L Fuel  $59,181
GPU electrical  -$2,200
Saving  $56,981 		Equipment (including taxes)  $56,625
Training  $2,300
Total  $58,925 		13 months

1. Based on $0.95 /L

Conclusion

Northern Thunderbird Air installed five ground power units at Vancouver, Prince George and Smithers, Edmonton and Calgary. Use of the GPUs to reduce aircraft engine time resulted in a projected reduction of 62,296 L of jet fuel per year, corresponding to cost savings of $56,981, and a reduction in GHG emissions of 161.8 tonnes.

The payback period is 13 months on equipment having an expected service life of 12 years or more. Had it been possible to measure the savings in space heating costs, the payback period would be further reduced.

Date modified:
2012-02-16