A California developer hopes to convert Molokai to a 100 percent renewable energy power system.

Steve Taber, chief executive officer of California-based Princeton Energy Group, is proposing to replace Molokai’s lone diesel-fired power plant with a renewable energy system featuring solar and hydroelectric power. Taber says he will soon submit a formal proposal to sell the electricity to Maui Electric Co., which, under Taber’s plan, would continue to operate the island’s grid with power provided by Princeton Energy.

Taber has been meeting with Molokai residents to brief them on his company’s plan that includes 80 acres of solar photovoltaic panels and a pumped storage hydroelectric project that would make use of water in an existing Molokai Ranch reservoir to turn an electric turbine.

"We want to get to 100 percent renewable. This is a project that a lot of people are excited about. It’s getting a lot of attention because it’s never been done to take a modern electrical grid this size and convert it from 100 percent carbon-based fuels to 100 percent renewable."

Currently, almost all the utility-provided electricity on Molokai is produced by nine diesel generators at one MECO power plant near Kaunakakai.

Taber’s plan calls for using solar energy during sunny days to power the grid and to pump water uphill. At night that water will be allowed to flow downhill through a turbine to generate power. The PV and pumped hydroelectric project would satisfy 80 percent to 90 percent of the island’s power needs, Taber said. The remaining 10 to 20 percent would come from the existing MECO power plant after converting the generators from diesel to biodiesel units, he said.

The project, dubbed Ikehu Molokai (or Energy Molokai), is in the early planning stages and would have to clear a number of regulatory and financing hurdles before becoming a reality.

Taber said he is in talks with MECO about purchasing the power and hopes to break ground by mid-2015.

"It’s going to be challenging to get the numbers to work. It’s going to be challenging to raise the money," Taber said. "But I would also say that we’ve got a real good track record of doing difficult things, so I’m pretty confident we can get this done."

Taber already has Molokai Ranch on board. The ranch would provide the land for the project.

Taber said the project would cut energy costs for ratepayers, but he would not say by how much.

The residential rate for electricity on Molokai was 47.5 cents a kilowatt-hour in November, the second highest of any island in the state after Lanai at 47.7 cents a kilowatt-hour, according to data from the state Department of Business, Economic Development and Tourism.

A spokeswoman for MECO said she was limited in what she could disclose because the plan was still in the early stages.

"Maui Electric has had preliminary discussions with this developer. While it is very premature at this point, our goal is to insure that any project we consider for Molokai makes sense for the island and the community and is an option that is cost-effective for our customers," said MECO’s Kaui Awai-Dickson.

Members of I Aloha Molokai, a community group that successfully opposed plans to build a utility-scale wind energy project on Molokai, said it was reserving judgment on Princeton Energy’s proposal until more questions could be answered.

One concern is that the proposed project not diminish the ability of Molokai residents to put up their own rooftop PV systems, said Kanohowailuku Helm, I Aloha Molokai president.

He said the group also wants assurances from Maui Electric Co. that the project would bring down electrical rates on Molokai.

"If Princeton is selling the electricity to MECO for, say, 20 cents a kilowatt-hour, what does MECO want to charge us? That’s a big factor," Helm said. "What’s missing is how much will this bring our bills down," he said.

Princeton Energy Group is largely a wind developer but has done some solar and energy efficiency projects, Taber said. Some of Princeton’s larger undertakings include a 12-megawatt wind project in Turkey and a 67-megawatt wind project in Mexico that included work done by a Princeton affiliate.

Princeton’s plans for Molokai call for a 17-megawatt solar farm on 80 acres near the Manila Camp area.

The second major piece of the project would be a hydroelectric generation system using water from a Molokai Ranch reservoir in the mountains above Kaunakakai. Princeton would build a second reservoir downslope and allow the flow of water from the upper to the lower reservoir to turn a turbine. Excess electricity from the solar farm during the day would be used to pump the water back uphill.