Last month, the proposed $4.3 billion NextEra Energy acquisition of Hawaii's electric utility HEI was approved by utility shareholders. In April, the Federal Energy Regulatory Commission approved the proposed acquisition.

But the big hurdle is Hawaii's Public Utilities Commission.

The acquisition still requires approval by the PUC, which is accepting comment from "intervenors" including AES Hawaii (coal plant owner and operator), Blue Planet Foundation, Hawaii Gas, Ka Lei Maile Ali'i Hawaiian Civic Club, SunPower, SunEdison, Hawaii Island Energy Cooperative, Kauai Island Utility Cooperative, Puna Pono Alliance, The Alliance for Solar Choice, and the Department of Defense.

According to the Honolulu Star-Advertiser, "two state agencies -- the Office of Planning and the Department of Business, Economic Development and Tourism" are claiming that the sale, as now structured, “should not be approved.” Both state agencies are part of the group of 28 intervenors, several of which have also expressed reservations about the deal.

Hawaii Gov. David Ige said he opposes the acquisition and is recommending that the PUC "reject the deal," according to the report. (The head of the PUC, Randy Iwase, was appointed by Gov. Ige earlier this year.)

“When we first met with NextEra, we were very clear that we had serious reservations about its proposal,” Ige said in a statement to the Honolulu Star-Advertiser. “Those reservations remain, and if anything, are stronger today.”

The acquisition process prompted Alan Arakawa, mayor of Maui County, to suggest, "We could start our own utility. We could purchase the electric companies. We could form cooperatives," according to earlier reports. (Kauai's KIUC is already a co-op -- the Garden Island's inhabitants purchased the electric utility for $215 million in 2002.)

The Hawaii Island Energy Cooperative has proposed a co-op business model for the Big Island. Marco Mangelsdorf is helping to lead that effort and was quoted in the Hawaii Tribune as saying, “Using existing KIUC staff on a part-time basis, adding a relatively small number of additional staff at KIUC (whether located on Hawaii or Kauai), and fully utilizing the 360 HELCO employees, we believe that HIEC could become fully operational at a lower cost than HECO is currently billing HELCO while still providing for incremental margins to KIUC, which would benefit their ratepayer owners by lowing their cost of management overhead."

NextEra owns and operates about 17 percent of installed U.S. wind capacity, about 14 percent of installed U.S. utility-scale solar, and eight nuclear reactors. As of year-end 2013, the utility giant had revenues of approximately $15.1 billion, approximately 42,500 megawatts of generating capacity, and approximately 13,900 employees in the U.S. and Canada.

HEI supplies power to almost a half-million customers on Hawaii, Oahu and Maui. Hawaii has the highest electricity prices in the U.S., and roughly 75 percent of the island's electrical power comes from imported oil. The entire island chain of Hawaii has just 2,400 megawatts of generating capacity. One in nine Hawaiian residences are PV-powered, the highest percentage of solar penetration of any U.S. state. MJ Shiao, GTM Research solar director, has noted, "HEI is the case study for high-penetration PV -- and the potential benefits and pitfalls of advanced PV integration regulations and technology."

Alan Oshima, HECO president and CEO issued a statement: "We recognize that this proposed merger is a very important matter for our customers, our communities and the state at large. The PUC review is an ongoing process that provides an opportunity to address and answer questions or concerns. As more information is provided throughout this process, we feel strongly that others will also conclude that this partnership with NextEra Energy will result in significant benefits for our customers and for Hawaii's leadership in clean energy."

Hawaii's PUC and the band of intervenors are set to consider the merger through the fall, which would push a final decision out until spring of next year.