Market Insights

Researchers Explore ‘SolarEV City’ Systems in Indonesia

February 17, 2023 by Shannon Cuthrell

A new techno-economic analysis from Japanese researchers backs the concept of pairing rooftop PV systems and EV batteries to meet electricity demands while reducing emissions in Jakarta, Indonesia. 

A study from researchers at Tohoku University in Japan explores the cost-effectiveness and environmental benefits of installing rooftop solar photovoltaic (PV) systems integrated with electric vehicle batteries. 


Jakarta, Indonesia. Image used courtesy of Tom Fisk via Pexels


Using techno-economic analysis methods, the study focused on deploying “PV + EV” systems—such as vehicle-to-home or vehicle-to-building technologies—in the Indonesian city of Jakarta, a low-latitude metropolitan area with a tropical climate and growing population topping 11 million people. 

The researchers found that PV-only systems would become increasingly cost-effective in Jakarta by 2030, ranging from 8% to 15%, and the widespread adoption of rooftop PVs paired with EVs as batteries could reduce carbon dioxide (CO2) emissions by about 75%—simultaneously serving electricity that's 33–34% cheaper than Jakarta’s existing energy infrastructure in 2030. The study’s authors termed the concept “SolarEV Cities.” 

The study was published in Applied Energy, a journal covering energy conversion, conservation, resource use, and other related topics. 


SolarEV City

The study’s lead researcher is Takuro Kobashi, an associate professor in Tohoku University’s Environmental Studies for Advanced Society program, who proposed the “SolarEV City” concept a few years ago in a study focusing on Japanese urban areas. He and his team ran analyses on eight major Japanese cities and certain regions within Tokyo, finding that combining EV and PV systems can help meet 53% to 95% of electricity demands by 2030. That paper was published in the journal Environmental Research Letters in February 2021.


Tokyo. Image used courtesy of Pixabay

A separate study published in Applied Energy in January 2022 found that integrating rooftop PV systems with standalone batteries or EVs produces more benefits in residential districts than commercial ones because rooftop space is more abundant and EV units are more prominent. 

Kobashi and his team found that Jakarta’s iteration would yield more significant benefits than the concept's earlier implementation in Kyoto. While Jakarta’s tropical climate has no space heating demand, it does have persistent cooling demand that would benefit from solar PV generation, increasing the decarbonization potential of PV/EV systems by 9% more than in Kyoto. Further, in a press release, Kobashi noted that the year-round high sun altitude angle would mean rooftop solar systems are less impacted by slope angles and orientation than other cities. 

This latest study focusing on Jakarta differs from Kobashi’s previous research on the topic because it’s the first time the concept has been explored in a developing city context. The paper points to the larger economic potential of PV + EV systems on Jakarta’s quality of life and economic development, arguing that adopting new decarbonization methods would support Indonesia’s goal to reach the status of a developed country by 2045. Jakarta also aims to reduce greenhouse gas emissions by 30% by 2030.