The commission voted 2-0 against the proposed transaction, citing its failure to prove that the acquisition was in the public’s interest.

The regulatory panel’s concerns over the deal included benefits to ratepayers, risks to ratepayers; clean energy commitments; change of control’s effect on local governance; and the proposed Change of Control’s effect on competition in local energy markets.

As per the deal signed in 2014, shareholders of HEI will receive NextEra Energy's 0.2413 shares for every HEI share and a one-time special cash dividend payment of $0.50 per share.

The transaction involved the assumption of $1.7bn in HEI debt and excluded banking subsidiary of HEI.

Hawaii aims to generate 100% of power from renewable sources by 2045 while also converting more cars to run on electricity.

The commission described NextEra’s commitments to supporting Hawaii’s green energy goals   as simply too broad and vague.

Following the termination of the deal, HEI said it plans to operate as an independent company.

HEI president and CEO Connie Lau said: "While the merger would have provided significant benefits for Hawaii, HEI remains a strong company that is well-positioned to achieve our goals and provide long-term value for our customers, community, employees and shareholders.”