Blackstone Inc.​ ​will invest $400 million in Xpansiv, a platform that lets investors trade assets tied to the energy transition such as carbon offsets and renewable-energy credits​.​

The upstart exchange is trying to provide the tools needed to standardize prices for carbon in the financial system. Analysts say that is a vital step to spur emissions reductions by large companies. Xpansiv formed a partnership with CME Group Inc. to last year launch futures contracts tied to voluntary carbon offsets.

Blackstone believes Xpansiv is in a sweet spot in the energy transition because it provides information that businesses and investors will need, said David Foley, global head of Blackstone Energy Partners.​ ​“The demand for it is just exploding,” he said.