Marubeni Corporation officially registered a new entity named Marubeni Power Trading, according to National Tax Agency records published in August. The company, created as a 50:50 joint venture with British energy trader SmartestEnergy, aims to develop physical electricity trading as well as energy and fuel derivatives products in Japan.
According to information from sources familiar with the matter, the joint venture will capitalise on Marubeni’s domestic market presence and SmartestEnergy’s trading expertise in liberalised markets such as the UK and Australia. The entity is also considering offering fixed-price products outside the areas operated by Tokyo and Kansai transmission system operators (TSOs).
Strategic diversification in a transitioning market
Marubeni began retailing electricity in 2000, when the Japanese market opened for extra-high voltage electricity sales. The company expanded its presence in 2004 and 2005 with entry into the high-voltage segment, before launching Marubeni Power Supply in 2011, rebranded as Marubeni Power Retail in 2015. Since the full liberalisation of 2016, Marubeni has also been serving low-voltage customers.
In May 2025, Marubeni Power Retail ranked third among new electricity suppliers in terms of total volume supplied, behind Tokyo Gas and Ennet, according to the latest available data from the Ministry of Economy, Trade and Industry (METI). It also held second place in the high-voltage segment and third in extra-high voltage, although its position remains limited in the low-voltage market.
SmartestEnergy expands its global footprint
Founded in 2000, SmartestEnergy initially aggregated generation assets in the UK before entering the commercial and industrial power retail market in 2008. The company later expanded operations with offices in the United States in 2019 and in Australia in 2020. It joins a group of international players such as Goldman Sachs, Vitol, Axpo and MFT Energy, which have recently increased their presence in physical trading in Japan.
The Japanese market offers new opportunities following the shift from a fixed-price feed-in-tariff scheme for renewables to market-based mechanisms. Additionally, the growth of grid-scale energy storage projects and increased demand for hedging tools are driving development in energy futures trading.
The joint venture between Marubeni and SmartestEnergy illustrates a model of cooperation in which European trading expertise in mature markets is deployed to enter the Japanese market without the need to build full local origination capabilities internally.
