IEEE Spectrum has a look at a new OTEC pilot plant in Hawaii - Ocean Thermal Energy: Back From the Deep.

The finished facility, which will be only a bit higher in capacity than existing test plants in Japan and South Korea, is quite modest by energy production standards. The plant will be able to produce at most 100 kilowatts of power—enough, when operating continuously, to supply electricity to about 80 average American homes.

The plant and its pumps will consume most of the energy produced. But Makai’s plant is geared toward research, Eldred notes, not energy generation. The facility was built primarily to design and test heat exchangers, which are among the most expensive components of an OTEC plant. With the addition of a turbine, Eldred says, Makai will be able to design an automatic control system and improve both performance and cost predictions for its commercial plant designs. The company also hopes to get a sense of how fluctuations in the temperature and pressure of ocean water will alter power output, a factor that might prove significant for wave-tossed offshore plants.

That’s likely to be where OTEC energy production winds up. A 10-megawatt plant, such as one that Lockheed Martin aims to build for China’s Reignwood Group, will require a cold-water pipe that is several meters wide. A plant floating in open water could send a pipe straight to the depth required instead of diagonally, down a long slope extending out from shore. That would make for a shorter and less expensive pipe, reduce the impact on the landscape, and cut down on the energy required to pump the cold water.

The first large-scale plant to make the leap could be New Energy for Martinique and Overseas (NEMO), says Luis Vega of the University of Hawaii’s National Marine Renewable Energy Center. The project, which is a collaboration between renewable energy firm Akuo Energy and naval defense company DCNS, both based in Paris, plans to construct a 16-MW plant about 5 kilometers off the shore of the island of Martinique.

Construction is set to start next year, and the team aims to have the plant operational in four years. When complete, NEMO should be able to supply some 11 MW of energy to the Caribbean island, with the other 5 MW powering the plant and its pumps.

RNE has a look at moves in Hawaii to shift from oil-fired power generation to solar power - Hawaii utilites capitulate on solar, in 65% renewables plan.

Just months after being ordered to lift their game on distributed, grid-connected solar, Hawaii’s investor-owned electric companies have revealed plans to triple the amount of rooftop solar installed on the island state by 2030.

Hawaiian Electric, Maui Electric and Hawaii Electric Light, collectively known as HECO, announced on Wednesday plans to upgrade the grid and boost solar as part of a broader goal to achieve a minimum of 65 per cent renewable energy generation and to cut electricity bill costs by 20 per cent – also by 2030.

In late April, HECO came under direct pressure from Hawaii’s energy regulator, which ruled the utilities were not moving fast enough to address key sources of customer frustration, namely challenges connecting solar PV systems to the grid.

Yet another announcement from Project Better Place, this time spreading their wings to Hawaii - Hawaii goes electric.

California's announcement last month of its aim to turn San Francisco Bay into the world's electric car capital has been followed by Hawaii jumping on the clean energy bandwagon.

The state spends up to $7bn (£4.75bn) a year on importing oil, and cars account for almost 20% of the state's greenhouse gas emissions.

In a mirror of the Californian plans, the electric transportation company Better Place will aim to build a network of kerbside charging points across Hawaii and create the equivalent of filling stations, where electric car owners will be able to replace their flat batteries for fully charged ones. With a full charge, a typical car will be able to travel 100 miles, ideal for commuting around urban areas.

Governor Linda Lingle yesterday called it "a significant move towards our state gaining independence from foreign oil". She added: "This public-private partnership is exactly the type of investment we have been working on as we continue to carry out our Hawaii clean energy initiative, moving toward the goal of 70% clean energy for the state of Hawaii."

Shai Agassi, chief executive of Better Place, said: "Hawaii, with its ready access to renewable energy resources like solar, wind, wave and geothermal, is the ideal location to serve as a blueprint for the rest of the US."

Better Place will begin introducing cars to test its Hawaii network in 2010, with mass-market cars available in 2012. Israel, Denmark and Australia have also signed up for the scheme.

OTEC News reports that there may be a second OTEC plant planned for Hawaii - Not one, but two OTEC plants in Hawaii? .

Thanks to Maria Tome, Hawaii State Energy Office for confirming that the Lookheed Martin OTEC will be built on Oahu, Hawaii. She pointed to this Energy Agreement which was signed by the State of Hawaii and the Hawaiian Electric Companies.

Looking a little deeper into the 52 page agreement (2 MB PDF) I found something which I hadn't seemed mentioned before, and I am not sure I understand what it means. On page 45 in the document it says "Cumulative Target Goal (MW per year end)", and has a table. The Lookheed Martin OTEC is in there with 10 MW. But there is a second line with "Sea Solar OTEC 100 MW", to be in place at the same time as the Lookheed Martin installation. Sea Solar OTEC shows up on page 49 as well and as having a "completed term sheet" by Q3 2008, and a proposed "commercial operation date" of Q3 2013.

Is there a separate OTEC plant being negotiated with Sea Solar Power for Oahu, Hawaii?