Wind and solar energy producer NextEra Energy has reportedly made an offer of roughly $15bn to acquire US power utility Evergy.

Established following the merger of Great Plains Energy and Westar Energy in 2018, Evergy currently serves 1.6 million customers in Kansas and Missouri.

The takeover offer made by NextEra Energy was rejected by Evergy, people familiar with the matter told Reuters.

Evergy, however, informed NextEra that the offer price was inadequate. It also needs a detailed plan that addresses regulatory obstacles to complete the potential deal, the sources told the new agency.

An Evergy spokeswoman was quoted by the news agency as saying: “As previously discussed… we conducted an extensive strategic review process, that process is complete, and our attention is focused on our sustainability transformation plan.”

Earlier this year, Evergy signed an agreement with affiliates of Elliott Management, which held an economic interest equivalent to approximately 10 million shares of Evergy’s common stock.

As per the agreement, a new Strategic Review & Operations Committee is planned to be launched to focus on exploring ways to enhance shareholder value.

NextEra serves more than 5.5 million customers in Florida, through its two electric companies.

In September, NextEra Energy subsidiary NextEra Energy Transmission signed an agreement to acquire GridLiance Holdco and GridLiance, from Blackstone Energy Partners for $660m.

Through two separate deals, NextEra Energy Resources recently agreed to sell a 90% stake in a 1GW renewables portfolio and a 100% stake in a 100MW solar-plus-storage project in the US to NextEra Energy Partners (NEP) and a consortium led by KKR.