TUHO: The analysis becomes very interesting when the researchers leave freight behind and start thinking about what could be done with many big, mobile batteries. Even without moving them, freight companies could use their capacity to provide grid stabilization services or sell back power when the price gets high. In extreme cases, this system could actually pay for the entire infrastructure.
"Preliminary estimates of the most expensive 90 hours per year in the ERCOT [Texas] market, for example, show that batteries could be discharged at $200/kWh, potentially generating enough revenue to pay for the upfront battery cost in a single year," the study says.
The batteries could also be moved to locations that have been struck by power outages or natural disasters, towed there by locomotives running on diesel instead of draining the batteries.
All of this would add considerable levels of complexity to the task of supplying freight companies with the energy needed to do their primary job of moving material around. Getting the most out of the batteries might involve constantly running the numbers on electricity and diesel prices and comparing the result to charging capacity and shipping deadlines. But if done right, the idea has the potential to bring zero emissions to an otherwise difficult-to-decarbonize form of transportation.