Which would be more CO2 emissions for drone and truck transport?

Amazon in 2016Delivery experiment using droneAnd the future that "parcels can be delivered from the sky in a matter of tens of minutes" is nearing realization. As a result of research by the University of Washington that Washington University studied which of the trucks and drone is environmentally friendly in terms of CO2 emissions in the practical application of drone delivery instead of traditional truck delivery, "As a result of distance and weight of luggage Unexpected result of appearance appeared.

Transportation Research Part D: Transport and Environment - ScienceDirect.com
http://www.sciencedirect.com/science/journal/13619209

Drone vs. truck deliveries: Which create less carbon pollution? | UW Today
http://www.washington.edu/news/2017/05/30/drone-vs-truck-deliveries-which-create-less-carbon-pollution/

Professor Anne Goodchild of the University of Washington University's Civil Engineering and Environmental Engineering Department conducted a study to compare the environmental load of delivery using trucks and drone. The comparison uses 10 scenarios set in Los Angeles where 330 service areas, each with 50 to 500 recipients, are set up. Researchers assume that Drone can carry only one parcel and needs to go round and trip from base station for each delivery.

As a result of comparative experiments, drone is a short distance flight carrying lightweight baggage, few customers and fewer delivery routes It was found that high energy efficiency is demonstrated in areas not involved and there is a possibility of realizing less CO2 emissions than trucks.

However, in any situation, drone is not environmentally friendly, but drone said that the heavier the weight of the package to be delivered, the lower the energy efficiency, so the CO2 emissions will also increase. In this case, for trucks that can carry a large number of cargoes at once, when there are many unloading points on the delivery route, or when delivering to areas away from the central warehouse, CO2 emissions are less than drone I also know that.

The heat map showing the difference between drone and truck CO2 emissions is as follows.


About this result Professor Good Child says, "We can propose a hybrid approach of delivering a short distance last one mile by drone while delivering a large number of items in the truck at the center of the delivery area."

The cargo carrier UPS has already tested the hybrid truck with the drone takeoff and landing station on the truck. It is a system that skips a drone in a place where a truck can not enter, and delivers other luggage manually with a truck in the meantime, and drone is able to track the moving truck through GPS and return it. You can see the details by reading the following article.

UPS of a shipping company started testing to deliver goods to the eaves by skipping a drone from a home delivery truck - GIGAZINE