Kraken vs Kaluza: the software running your energy supplier
The two most widely used energy software platforms to come out of Britain were both built inside retail suppliers, then spun out to sell to rivals. Octopus built Kraken. OVO built Kaluza. The platform behind your supplier decides how billing, smart-meter data and customer service actually run, so it is worth knowing the difference.
Kraken (Octopus Energy)
Kraken is an end-to-end operating system for utilities: it handles customer accounts, smart-meter data, billing and grid balancing. Octopus formally spun it out in December 2025 at a valuation of $8.65 billion. It runs more than 70 million contracted accounts across over 40 utilities, including EDF, E.ON Next, Origin Energy in Australia and Tokyo Gas in Japan.
Kaluza (OVO Energy)
Kaluza was spun out of OVO in 2019. OVO holds an 80% stake. It services around 20 million consumers and recently signed a multi-year deal with ENGIE to run up to 20 million accounts. Kaluza leans toward device and flexibility management, the software that schedules EV charging, batteries and heat pumps around cheap and clean periods.
Why the platform affects you
When a supplier sends an accurate bill, applies a time-of-use tariff correctly, or surfaces your half-hourly smart-meter data in an app, that is the platform at work. A supplier on a modern platform tends to score better on the parts of service that are really data plumbing. It is one of the reasons Octopus and the suppliers running Kraken often rate well on the technology and service measures in our supplier rankings.
The twist in 2026
E.ON Next, which runs on Kraken, agreed in May 2026 to buy OVO's energy retail business. Kaluza is not part of that deal. It stays with OVO Group, and on completion E.ON keeps the existing Kaluza licence for the OVO customers it takes on.
That sets up an unusual position: one supplier running both platforms at once. E.ON Next's existing customers stay on Kraken, while the migrated OVO customers stay on Kaluza, under the same company and drawing on the same E.ON data and infrastructure. Two operating systems competing for the same customer base on billing accuracy and new features tends to push both harder. The household using the result is the one who gains, which makes this a live test of how much the back-end software now shapes what a supplier can offer.