If ever a time was to come in which delivery robots would come into their own, it was during a pandemic in which not only did e-commerce boom but social distancing rules meant that providing safe delivery of goods was paramount.

Alas, that didn’t really occur, and delivery robots were instead replaced by an ever-growing army of delivery drivers scooting about our towns and cities on bikes.  Not only are delivery robots not appearing to make any practical inroads into the last-mile market, but research from the University of Michigan also suggests they don’t even make a positive contribution to lowering our carbon footprint.

Carbon footprint

The researchers examined the environmental impact of not only automated delivery systems but also the human-based methods that dominate the market.  The analysis found that while the delivery bots only contribute around 20% of the overall carbon footprint of the package they’re delivering, most of those emissions come from the vehicle itself.

The key factors in the sustainability of the robots are the powertrain and the fuel economy, with a switch to electric power trains and green sources of that electricity the steps likely to have the biggest overall impact.

“We found that the energy and carbon footprints of this automated parcel delivery in suburban areas was similar to that of conventional human driven vehicles. The advantages of better fuel economy through vehicle automation were offset by greater electricity loads from automated vehicle power requirements,” the researchers say.

“For all delivery systems studied, the vehicle-use phase is the single largest contributor to greenhouse gas emissions, highlighting the need for low-carbon fuels for sustainable parcel delivery. It is critically important to decarbonize grids while deploying electrified vehicles.”

Optimizing the last mile

The demand for e-commerce during Covid renewed interest in autonomous delivery systems again after the original clamor around vendors such as Starship technologies has waned in recent years.  A number of companies have either begun or renewed pilots of autonomous delivery services in a bid to make a dent in a market estimated to be worth nearly $12 billion by 2030.

The last mile is traditionally the most expensive leg of the product’s journey, both in financial and environmental terms.  The authors estimate that autonomous systems could reduce costs by up to 40% in cities, but their environmental impact is less clear-cut.

The researchers analyzed a range of different vehicle platforms and delivery scenarios to try and gauge the possible environmental impact of the technology.  The analysis revealed that the most eco-friendly option was provided by the smaller, electric vans.

“Results suggest that automated delivery systems could have slightly greater life cycle greenhouse gas emissions than conventional delivery systems for smaller-sized vans, but there is potential opportunity to reduce emissions for larger-sized vans,” the researchers say. “Compared to the conventional scenario, full automation results in similar greenhouse gas emissions for the large gasoline powered cargo van, but 10% higher for the smaller battery electric van.”

In reality, it’s unlikely that a single system will be used across all scenarios, and if automated technologies do crack the market there are likely to be multiple approaches deployed in scenarios best suited to their particular technology.  With climate change and sustainability an ever-increasing factor, however, it’s perhaps something for vendors to also keep working on.