Fast-reacting 50 MW power plant planned for Hawaii's solar revolution

Hawaii is making plans to shift solar into its power generation spotlight after announcing that Wärtsilä corporation is to supply a 50 MW power plant designed specifically to aid the development of solar energy in the state.

The project, which requires approval by the Hawaii Public Utilities Commission, would see Wärtsilä install a Smart Power Generation power plant on the island of Oahu, which will be owned and operated by Hawaiian Electric Company. The utility already generates 18% of its energy via solar sources, and hopes to up that share to 65% by 2030.

The addition of a 50 MW smart power plant – fueled by internal combustion engines (ICEs) that run on a biofuel blend of liquid fuels and natural gas – will lower the island’s dependence on oil and coal-based power generation. The ICEs’ fast-reacting nature makes them ideal for running on multiple fuels, meaning solar power can be ushered into the driving seat as more capacity is added.

According to the Interstate Renewable Energy Council, Hawaii has the highest per capita installed capacity of PV systems of any U.S. state, delivering 255 watts per person compared to the U.S. average of 37.9 watts per person. Across the state, 12% of all residential dwellings have solar panels installed.

The project would see Wärtsilä install six 34DF engines with a combined output of 50 MW at Schofield Barracks Army base, some 40 km from Honolulu. If approved, the power plant would begin operation in 2017, transforming Hawaiian Electric Company’s generation portfolio into a more flexible, future-proof operation. “ICEs provide a solution to our requirements, since they are fast-reacting, efficient and capable of running on multiple fuels,” said Hawaiian Electric senior engineer Jack Shriver.

"We can start them up multiple times daily, reach full load in less than 10 minutes, and shut them off whenever we don’t need them. As the amount of solar power on the island continues to increase, we will reach the point where during sunny days we will need to ramp down our existing steam units more than they were designed to do," Shriver added.

Wärtsilä’s regional director Wayne Elmore said that solar energy’s intermittent nature meant a grid needed something that was able to "fill the gaps quickly".

"We are thrilled to see that our Smart Power Generation technology is a perfect companion to variable renewable energy," he said. "Fast back-up capacity not only supports but enables much more wind and solar. This is key to sustainable power systems."

A recent report by the International Energy Agency (IEA) on variable renewable power found that ICEs are a promising development in the support of solar and wind integration. The report compared different flexibility resources and found that gas-fired ICE plants are a "very mature technology" that are cost-competitive.