Electric bus depots can be ‘profitable energy hubs’

Research underway in China is exploring using plug-in public transport infrastructure for clean energy generation. 

Led by Xiaoyue Cathy Liu, an engineering professor at the University of Utah, the investigation is looking at Beijing’s 27,000 strong fleet of buses with the goal of ‘radically rethinking’ how public transportation systems are integrated into wider civic infrastructure. Researchers from China’s Beihang University, Sweden’s Chalmers University of Technology and Germany’s Fraunhofer Institute for Systems and Innovation Research ISI are also involved. 

China’s capital now runs 90% of its bus services with low or no-emission vehicles. The world’s largest public transport system, 700 charging depots are currently live across 6,500 square miles. The electricity demands of this vast fleet place a huge strain on the grid, so the team are now assessing whether localised solar generation could sufficiently counterbalance that demand, while economic factors that will determine feasibility are also being considered. 

‘More than meeting demand, our simulations show that these depots could net out to be energy producers, further stabilizing the grid,’ said Liu. ‘Integrating onsite solar power generation and energy storage at bus depots introduces a brand new renewable energy production and management mode, transforming a public transport depot into an energy hub that produces more electricity than it consumes.’

The study uses advanced data science  scene techniques, utilising a computer model of the Beijing bus network, real world air temperature figures and solar irradiance at each depot, taken during 2020. These numbers, combined with the rooftop surface area of each depot, mean the team can accurately predict the capacity for electrical output at each of the depots. 

‘We found energy storage to be the most expensive factor in the model, so smarter and strategic charging schedules would need to be implemented,’ Liu added. ‘That responsiveness is critical, as variable energy pricing schemes have such a large impact on the overall economics.’

More on transport: 

Aviation sector has two years to meet emissions reductions targets

Has the budget done enough to encourage EV adoption?

First Bus confirms five new electric bus charging depots across UK