I'm working on an airport project expansion project. The LEED coach told us that we have to include the airplane jet bridges, ground power units (GPU) and preconditioned air units (PCA). Becuase these are considered process energy, they are supposed to be identical in both baseline and proposed. I'm now stuck with two problems and I hope someone here can give me some advice - 

1. how can i estimate the energy consumption for these usages? i think i can estimate the duration how long these operates (let's sat 2 hours per each flight) but I dont think they all operate at their peak rated power during those time. 

2. is there any chance I can do exceptional calculation? We are barely beating the baseline right now so every saving measure counts. Maybe I can prove the reduced lighting power of the jet bridges. but what about the GPU and PCA? Can I assume the baseline is burning the jet fuel (look at how expensive the fuel is!) for the parked airport, and our GPU and PCA can reduce the energy cost by using the power from the airport. 

Thanks in advance!