Maui Electric Co. has modified its operations to use more wind-generated energy in the island's power grid, and there are plans to integrate the alternative energy further, the utility said Wednesday.
Plans call for deactivating two of four power-generating units at MECO's aging Kahului power plant in 2014 and retiring the remaining two units by 2019.
The current changes to MECO's operations are expected to result in an annual electric bill cost savings of $22 for a typical Maui resident, officials reported.
Now, MECO is using about 91 percent of available wind energy compared to an estimated 72 percent prior to making the changes, MECO said. With more changes, Maui Electric said it expects to increase the amount of wind energy used to roughly as much as 95 to 98 percent of what's available, and that could save a typical residential customer another $7 to $10 per year.
"We want to make sure our customers get the maximum benefit of our abundant wind energy resources while still getting reliable service," said Sharon Suzuki, Maui Electric president. "We've made a lot of progress and will be making further changes to ensure our customers benefit even more."
To increase the use of wind power, Maui Electric has:
* Modified some of its generator control systems.
* Reduced the use of the four generating units at its Kahului power plant.
* Fully incorporated the battery-energy storage system at Kaheawa Wind II above Maalaea.
Aside from deactivating generators at Kahului, MECO also plans to modify the use of generating units at the Maalaea power plant.
Maui Electric said its growing use of renewable energy includes wind power, biomass energy from Hawaii's last working sugar plantation, hydroelectric power and energy from photovoltaic systems. As of the end of 2012, 21 percent of the electricity used by Maui Electric customers came from renewable sources, the utility said.
To ensure safe, reliable electric service, Maui Electric uses some of its generators to balance the inconsistent output from renewable energy sources, like wind farms and photovoltaic systems. This output varies depending on wind speeds and direction, cloud cover, weather conditions and the time of day, officials said.
Maui Electric reported its efforts to incorporate wind power into its power grid in a filing Tuesday with the Hawaii Public Utilities Commission. The report covered other options such as implementing demand-response pilot programs, under which customers allow selected types of electrically powered equipment or appliances to be turned off in an emergency.
Other options proposed were installing a battery energy storage system or implementing measures to shift customer usage to certain time periods, upgrading transmission lines and implementing advanced metering infrastructure.
MECO's report came at the direction of the PUC when it issued a final decision for the company's 2012 rate request in May.