A bankable partner for generators: SmartestEnergy and Marubeni Corporation

Backed by 25 years of expertise, SmartestEnergy is a leading aggregator of renewable generation, connecting generators to customer demand and driving the net zero transition. With the support of Marubeni Corporation, a Fortune 500 company with an A- credit rating, we deliver bankable routes to market, innovative PPA solutions, and global expertise to help generators thrive in a changing energy landscape.

Providing a viable route to market through partnership

Since establishing as an aggregator of independent generators in 2000, SmartestEnergy Limited has provided a competitive route to market for a customer base of over 400 independent generators spanning the length and breadth of the UK.

We began with a unique proposition focused on supporting small independent renewable generators, and over time, we’ve expanded to serve larger generators, investors, and developers, reflecting the growing scale and sophistication of the market.

However, we know that the energy market isn’t just about buying and selling energy; ultimately, it’s about people and relationships. We work in partnership with our generators to provide the knowledge, insight and technology to help them grow. With a range of standard and bespoke power purchase agreements (PPAs), we work closely with our customers to help them manage risk, diversify revenue streams and maximise the value of their power, empowering them to thrive in a dynamic energy landscape.

Robust support from Marubeni Corporation

We are proud to be owned by Marubeni Corporation, a global powerhouse ranked No. 298 on the Global Fortune 500 list, with over 50,000 employees worldwide. Marubeni’s extensive resources and financial strength provide us with a stable foundation, allowing us to focus on growth and innovation.

In November 2025, Marubeni’s credit rating was upgraded by S&P Global Ratings from BBB+ (Positive) to A- (Stable), a testament to its robust financial position and sustainable growth strategy. This backing makes SmartestEnergy a bankable and creditworthy partner, empowering us to navigate energy market volatility confidently and assuring our customers that we can meet all contractual terms, even when faced with the most challenging times.​ With Marubeni’s support, we navigate energy market volatility with assurance and deliver long-term stability for our partners.

Scaling our capabilities globally

Leveraging Marubeni’s global reach, we’ve expanded beyond the UK, opening offices in the United States and Australia, and most recently forming a joint venture with Marubeni Power Retail Corporation (MPR) to modernise electricity trading in Japan.

And the growth doesn’t stop there. We are scaling our carbon, power and gas trading operations into continental Europe across the UK, Ireland, the Netherlands and most recently Germany, opening access to new customer opportunities and partnerships.

This international presence, combined with Marubeni’s innovative approach and financial backing, positions us as a resilient and bankable partner you can trust.

Navigating industry challenges with innovative solutions

The renewable energy sector faces several challenges, from regulatory hurdles and technological barriers to market competition. Navigating the complexities of an evolving energy system requires continuous adaptation and innovation.

With the strong backing of Marubeni Corporation, SmartestEnergy is equipped to tackle these challenges head-on. Our approach combines long-term contracts, competitive pricing, and strategic partnerships, giving customers the stability and confidence they need in a changing market.

By continuously adapting and investing in new technologies and trading capabilities, we help generators overcome uncertainty and unlock growth. Together, we are setting new benchmarks for excellence and sustainability, empowering the net zero transition by driving positive change in the system.