2026年7月21日、ドイツ東部バウツェン中心部にある容量1.5メガワット（1.5MW）のリチウムイオン電池エネルギー蓄電システム（4つのコンテナ構造）で火災が発生しました。

直接消火が困難なため、消防隊は毎分5,000リットルの放水による継続的な冷却とドローン監視を実施。爆発や熱爆走のリスクを抑えつつ、近隣住民42人を退避させるなどの避難措置を取りました。負傷者は報告されておらず、大気測定でも危険物質は検出されていません。

主な出来事のタイムラインと対応

• 7月21日（火災発生）： 旧市街の住民に窓の開放禁止やエアコン停止を勧告。近隣住民25人が避難。
• 7月21日夜間： 追加で17人が避難（合計42人）。毎時状況の更新を実施。
• 7月22日（現在）： 冷却作業と避難措置を維持。状況は安定傾向にあるものの、慎重な対応を継続。

関連情報・背景解説

1. なぜリチウムイオン電池の火災は鎮火が難しいのか？

リチウムイオン電池火災の最大の課題は熱暴走（サーマルランナウェイ）と呼ばれる連鎖反応です。 一度内部でショートや過熱が起きると、電池自体が酸素や可燃性ガスを放出しながら自己発熱を続けます。そのため、外部から酸素を遮断する通常の消火方法が効きにくく、水などで大量に冷やし続けて連鎖反応を止めるのが標準的な対処手順となります。

2. コンテナ型蓄電池システム（BESS）の普及と課題

再生可能エネルギー（太陽光や風力）の導入が進むドイツでは、電力網の安定化を目的としたコンテナ型電池電力貯蔵システム（BESS = Battery Energy Storage System）の設置が急増しています。 一方で、今回のように市街地近くに設置された大型コンテナでの火災は、周辺住民への影響や消火活動の難易度が高く、設置場所の基準や最新の自動消火設備の導入など、安全対策のさらなる見直しが求められています。

出典：https://www.ess-news.com/2026/07/22/fire-breaks-out-at-1-5-mw-battery-storage-system-in-germany/?utm_source=Energy+Storage+%7C+Newsletter&utm_campaign=65c9984157-daily_nl_ess&utm_medium=email&utm_term=0_340f72e33a-11dae14eca-494474286&ct=t(dailynl_ess)

[Germany] Fire at 1.5MW Lithium-ion Battery Facility: Current Status of Resident Evacuations and Cooling Operations

On July 21, 2026, a fire broke out at a 1.5 megawatt (1.5MW) lithium-ion battery energy storage system housed in four containers in the center of Bautzen, eastern Germany.

Because direct extinguishing is difficult, firefighters are continuously cooling the site with 5,000 liters of water per minute while monitoring the area with drones. To mitigate the risk of explosions and thermal runaway, evacuation measures were taken, including the evacuation of 42 nearby residents. No injuries have been reported, and air quality measurements have detected no hazardous substances.

Key Events Timeline and Response

• July 21 (Fire Outbreak): Residents in the old town were advised to keep windows closed and turn off air conditioners. 25 nearby residents were evacuated.
• Overnight, July 21: An additional 17 residents were evacuated (total of 42 people). Hourly status updates were provided.
• July 22: Cooling operations and evacuation orders remain in place. While the situation is stabilizing, cautious management continues.

Related Information and Background

1. Why Are Lithium-ion Battery Fires So Difficult to Extinguish?

The biggest challenge with lithium-ion battery fires is a chain reaction known as thermal runaway. Once an internal short circuit or overheating occurs, the battery continues to generate heat while releasing oxygen and flammable gases from within. As a result, standard firefighting methods that cut off external oxygen supplies are largely ineffective, making continuous cooling with large amounts of water the standard protocol to stop the chain reaction.

2. The Rise and Challenges of Battery Energy Storage Systems (BESS)

With the rapid adoption of renewable energy such as solar and wind power, Germany has seen a surge in the installation of containerized Battery Energy Storage Systems (BESS) to stabilize the power grid. However, fires involving large container units near urban areas, like this incident, pose significant challenges for firefighting and impact local residents. This highlights the need to re-evaluate safety measures, including location standards and the installation of advanced automated fire suppression systems.