Mainova

The City of Frankfurt am Main is the ultimate controlling entity through a 75.2% stake held by Stadtwerke Frankfurt am Main Holding GmbH, with Thüga AG owning the remaining 24.5%. This municipal ownership structure means Mainova's capital allocation blends public-utility duties — maintaining the Frankfurt district heating network and power plants — with opportunistic expansion into digital infrastructure and renewables, a posture distinct from purely profit-maximizing private investors.

Mainova WebHouse is a joint venture data center campus located in Frankfurt-Seckbach, developed in partnership with BlackRock's Global Infrastructure Fund. The campus, designated MWH01, leverages Mainova's municipal utilities expertise and local land position to supply energy and cooling infrastructure to a major European data center market. It represents Mainova's most visible move into digital infrastructure.

Mainova's investment activity appears concentrated in direct project development and joint venture partnerships rather than third-party fund commitments. The WebHouse data center was structured as a co-investment with BlackRock, and the 2023 cooperation agreement with Tishman Speyer points to additional project-level joint ventures.

Mainova's portfolio spans energy transition and renewables, core utility infrastructure, and digital infrastructure, particularly data centers. Traditional assets include the Frankfurt district heating network and biomass power generation, while newer activity centers on solar parks and data center campuses within the Rhine-Main region.

Mainova supports the Frankfurt Foundation for Children with Cancer (Frankfurter Stiftung für krebskranke Kinder), consistent with its position as a municipally rooted corporate citizen. The foundation is separate from the firm's investment and operational activities.