ENERES Co., Ltd.

ENERES Co., Ltd. has established Phase III (FY2024-2026) of the “Energy System Integration Social Cooperation Research Department (ESI)” with the University of Tokyo Institute of Industrial Science and 18 participating companies including ENERES. In FY2024, ENERES will research optimal combination logic for supplying low-voltage resources, including EVs (Electric Vehicles), as balancing capacity. This marks ENERES’s second consecutive participation in ESI research.

■Background

Toward making renewable energy the main power source, accurately and quickly supplying balancing capacity^[1]
to compensate for unstable renewable energy output has become a challenge. Low-voltage resources are attracting attention as power sources for balancing capacity. These include electric vehicles (EVs), which emit extremely low amounts of carbon dioxide while driving, and residential storage batteries installed alongside solar power generation (PV) in homes. EV batteries and residential storage batteries owned by power users are increasingly showing potential as resources for creating balancing capacity, as they can be flexibly utilized for power demand adjustment through IoT control, and are expected to become available for trading in the balancing market from FY2026.

■Challenges of Low-Voltage Resources as Balancing Capacity

A characteristic of low-voltage resources is that they have original purposes other than use as balancing capacity. For example, EVs are means of transportation, and residential storage batteries are for using stored power at night and during emergencies. To supply balancing capacity without interfering with these original purposes, it is important to understand unused time periods and surplus capacity, and create mechanisms to compensate for shortages and excesses. EVs in particular face challenges in predicting available balancing capacity because battery charge levels vary with driving distance, and even when parked, they may not be connected to V2H^[2].

■Research Content

To solve these challenges, ENERES has been a pioneer in demonstration projects utilizing low-voltage resources as balancing capacity, conducting demonstrations and research on the proportion, amount, and time periods of EVs that can be used for balancing capacity, targeting dozens of EVs.
In this year’s research with ESI, we will expand the scale of EVs under study and add residential storage batteries and heat pump water heaters. Using ESI’s ESIA^[3], we will simulate optimal combinations of low-voltage resources from the perspectives of available supply capacity and economic efficiency. Furthermore, we will research aggregation methods to build larger balancing capacity.
Specifically, we will investigate and research combinations of low-voltage resources that maximize both supply volume and market trading profitability by combining principles of electricity usage found from living patterns of electricity users on the premises with multiple elements such as “types of resources owned by households,” “presence of on-site power demand,” “whether EVs have returned to the premises,” “EV driving distance,” “time periods when EVs are connected to V2H,” etc.

The results of this year’s research are scheduled to be presented at the ESI reporting meeting to be held at the end of FY2024.

ENERES will continue to strengthen industry-government-academia collaboration while taking on the challenge of building new power systems that contribute to making renewable energy the main power source and realizing a decarbonized society.

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[1]Balancing Capacity:　Power procured by general transmission and distribution operators to maintain power supply-demand balance for maintaining power frequency

[2]V2H:　Abbreviation for Vehicle to Home. Equipment that enables the use of power stored in EV batteries within buildings on the same premises

[3]ESIA (ESI Aggregation) Model: Models the behavior when aggregators with multiple demands and numerous customer devices form balancing groups (BG) and procure power from the market, enabling verification of DR resource aggregation effects, market utilization effects, and imbalance burden elimination effects through real-time operations
ESI Overviewhttps://www.esisyab.iis.u-tokyo.ac.jp/