Tokyo's Campaign to Combat the Power Crunch

Tokyo's Energy Issues

Changes in the economy, international affairs, weather, and a number of other factors heavily influence a country's ability to reliably balance the supply and demand of energy. In Europe, Russia's military invasion of Ukraine has triggered a rise in fuel prices that remains a challenge. Meanwhile in Japan, the record cold wave in the winter of 2021 that coincided with a shortage of LNG (liquified natural gas) causing a supply crunch is fresh on people's minds.

Iwafune Yumiko, Project Professor at the Institute of Industrial Science, the University of Tokyo says that power shortages actually come in two types: shortages that happen only at certain peak times of day, and shortages that occur consistently throughout the duration of the entire period. Peak shortages tend to be more of an issue during the summer, while large overall power consumption tends to be a problem in the winter.

Demand in winter generally tends to be flat compared to the prominent spikes seen in summer. But with more lighting and heating equipment used to compensate for shorter daylight hours and the larger difference between indoor and outdoor temperatures, total energy consumption is greater. "In the summer, we can take steps to shift the peak hours as much as possible, but in the winter, depending on the day, we need to conserve power throughout the day in order to maintain the available supply."

What is the City Doing to Help?

Countries and regions across the globe are putting measures in place to ensure energy security. In Japan, the Tokyo Metropolitan Government (TMG) has been promoting its HTT campaign to "save (herasu)," "generate (tsukuru)," and "store (tameru)" electricity, undertaking numerous initiatives and offering support for households and businesses alike. The campaign includes subsidies for retrofitting homes with well-insulated doors and windows and for producing battery storage systems, vehicle-to-home (V2H) bidirectional chargers, and electric vehicles.

The TMG is also moving forward with preparations to mandate the installation of solar panels on new constructions, aiming to have the system go into effect in 2025. This reflects similar efforts by the U.S. state of California, which made solar panels a requirement for all new low-rise housing state-wide in 2020, and the EU, which has proposed making solar panels mandatory for all new homes by 2029.

"Generating electricity is naturally a useful strategy given that it increases the amount of power available just like saving electricity does, and storing it will play a crucial role in shifting demand from peak to off-peak hours. Solar power also contributes to decarbonization. The biggest challenge in my opinion isn't tackling new homes, though. It's insulating and retrofitting existing homes. But the TMG has allocated a sizeable budget for this."

Iwafune goes on to say that data needs to be used effectively to promote these HTT campaign initiatives. "All customers in Tokyo Electric Power Company (TEPCO)'s service area now have smart meters installed, and we can use the data from these meters to evaluate the effectiveness of electricity-saving and energy-storage efforts. For PR purposes, it's important that we conduct online energy audits based on this data so that we can compile solid pre-installation and post-installation data sets showing the difference solar panels and battery storage systems make. The TMG is also pursuing other cutting-edge endeavors like the Tokyo Digital Twin Project. The project aims to create a replica of Tokyo's infrastructure, economic activity, human flow, and other aspects of the city in cyberspace based on data from sensors and other sources. It would be great if data on energy could be included as well."

Iwafune also notes that while conventional power systems have adjusted supply to match demand, moving forward, demand response (DR) will be key. DR uses the Internet of Things (IoT) and other advanced technologies to control energy use to match supply.

"As it stands, a lot of batteries are only being used for the buildings where they're installed. But implementing a system that can control them externally would increase the flexibility of the area's power grid and help secure adjustable power. If building owners were compensated for the use of their battery storage systems, it would benefit both the building owner and the community. In fact, there's a program like that in California for customers who own home energy storage systems made by Tesla, a well-known electric vehicle manufacturer. They receive compensation if they agree to let the company dispatch their battery  to help relieve electricity shortages in the wider area."

Iwafune predicts that these types of programs at the local level will need to be implemented in the future. "I think we're going to need to focus more on the supply-demand balance in managing our energy needs."