Bangkok has in recent months experienced dangerous levels of air pollution.
Earlier this year, schools closed and military personnel were deployed to combat the pollution in the streets. Indeed, images of military and government officials spraying water were widely circulated.
These measures attracted public attention to air pollution, but will do little to mitigate the toxic smog caused by high levels of PM2.5 in the long run.
As a city on the front line of climate change, Bangkok should take advantage of policy windows opened by short-term crises to spur long-term investments into sustainable electricity and resilient transportation systems.
Combining solar photovoltaic (PV) with electric vehicles and public transportation is one path toward innovative and environmental solutions to the air pollution crisis rattling Bangkok.
Fortunately, investments in both have become much more attractive in recent years. Battery storage for renewable electricity is improving rapidly.
Furthermore, Bangkok will soon facilitate distributed solar rooftop PV systems by allowing "net billing", or the sale of excess PV electricity generation back to the grid.
At the same time, the streets of Bangkok hold great potential for improvement.
Anecdotal evidence shows that commute times to work are skyrocketing for some residents to more than three hours each way, much of the time spent idling in traffic.
Encouraging public transportation and car sharing -- for instance, by designating lanes for the exclusive use of shared public and semi-private vehicles -- would reduce reliance on personal vehicles, thereby alleviating congestion and emissions simultaneously.
Electrifying Thailand's tuk-tuks, songthaews, buses, motorcycle taxis, and other innovative transportation services is another way to minimise environmental impacts.
Aligning investments in renewable energy with investments in sustainable transportation could deliver large synergistic benefits.
For example, smart technologies can adjust the rates at which electric vehicles (EVs) charge in response to real-time changes in electricity supply and demand.
This means EV charging can be maximised during daytime hours, when solar PV produces the most electricity, and minimised in the evening, when there is no solar supply.
EVs can even temporarily discharge power to the grid during periods of peak demand. Owners of fleets of rental EVs are particularly well positioned to match charging to the grid conditions.
During times of extreme weather, such as sweltering heat or heavy precipitation, solar PV, EVs and smart grid technologies are ready to work together to create a more resilient network infrastructure.
Aligning investments in renewable energy with investments in sustainable transportation can also improve socio-economic outcomes.
Shared vehicles in Thailand are typically owned by small business owners, who rent out vehicles to drivers.
Investing in distributed solar alongside battery-powered tuk-tuks, songthaews, and motorcycle taxis could enable vehicle owners to provide power directly to drivers.
This would result in lower costs and stabilise their incomes, which are otherwise highly vulnerable to oil price fluctuations.
Taking advantage of local auto, battery and computer hard drive manufacturing infrastructure would also benefit the Thai economy and position Thailand as a global export leader in EVs, solar PV-based microgrid products, and power electronics that integrate solar PV and battery storage.
These benefits are not just theoretical possibilities. EVs are already widely available across Thailand. Moreover, the kingdom ranks as one of the most prepared nations in Asean to integrate high shares of intermittent solar into the grid.
Furthermore, through expanded regional grid interconnections and power trade, Thailand could reduce its oil reserve requirement and overall electricity supply without sacrificing security and reliability. Excess peak power could easily be sold to Malaysia and Singapore.
Today, greening the power and transportation sectors is constrained more by the policy environment and financial conditions than technological constraints, especially in Bangkok.
The time is ripe for change. Greening existing transportation options with clean electricity from solar PV would certainly do much to mitigate air pollution. It will also make Thailand a leader in clean technology and innovation across Asean and the world.
Noah Kittner, PhD, is a senior researcher in the Group for Sustainability and Technology at ETH Zürich and a former visiting researcher at Chulalongkorn University's Energy Research Institute. Sopitsuda Tongsopit, PhD, is an energy policy analyst at the University of California, Davis (UC Davis) Policy Institute for Energy, Environment, and the Economy and the UC Davis Institute of Transportation Studies.