From the Editors of
Solar-Hawaii.orgThe
Oahu Wind Integration Study (OWIS) recently released a study detailing the impact on the
Oahu grid if a total of 500 MW of wind energy and a nominal 100 MW of
solar power came online as is expected.
The study found that the 500 MW of wind and 100 MW of solar power
could eliminate the need to burn approximately 2.8 million barrels of
low sulfur fuel oil (LSFO) and 132,000 tons of coal each year while
maintaining system reliability, if a number of recommendations are
incorporated, including:
- Provide state-of-the-art wind power forecasting to help
anticipate the amount of power that will be available from wind;
- Increase power reserves (the amount of power that can be called
upon from operating generators) to help manage wind variability
and uncertainty in wind power forecasts;
- Reduce minimum stable operating power of baseload generating units to provide more power reserves;
- Increase ramp rates (the time it takes to increase or decrease
output) of Hawaiian Electric’s thermal generating units;
- Implement severe weather monitoring to ensure adequate power
generation is available during periods of higher wind power
variability;
- Evaluate other resources capable of contributing reserve, such
as fast-starting thermal generating units and load control
programs.
The study notes that assuring reliability will require further
studies, upgrades to existing and new infrastructure, as well as
specific requirements on the wind farms to be connected to the Oahu
system. With these and other proposed changes, the technical analysis
suggests, Oahu can accommodate increased wind and solar energy projects with minimal limits on output of renewable resources.
The Oahu Wind Integration Study was conducted by the Hawaii Natural Energy Institute (HNEI) at the University of Hawaii at Manoa, General Electric (GE) Company and the Hawaiian Electric Company (HECO). The National Renewable Energy Laboratory (NREL), part of the U.S. Department of Energy
(US DOE), assembled a technical review committee with representatives
of industry and academia which met throughout the project to review
findings. NREL also contracted the private firm AWS Truepower to develop
wind and solar energy profiles that were used in the study.
“The findings of this study show it is feasible to integrate
large-scale wind and solar projects on Oahu but also have value beyond
Hawaii. Both large mainland utilities and relatively small and/or
isolated grids that wish to integrate significant amounts of renewable energy while maintaining reliability for their customers can learn from this study,” said Dr. Rick Rocheleau, HNEI director.
“GE has been working closely with HNEI and HECO to assess innovative
solutions to help Oahu meet its electricity demand with very high levels
of renewable resources,” said Hamid Elahi, GE Energy Consulting general
manager. “GE is proud to be working closely with HECO and other
forward-thinking utilities which are leading the industry in solving
some of the most important challenges that face our grids.”
Robbie Alm, Hawaiian Electric executive vice president, said, “To
reach our renewable energy goals we need to use all the resources
available to us. For Oahu, this includes the utility-scale solar,
roof-top solar, waste-to-energy and on-island wind that we are pursuing.
But on-island resources are not enough to meet Oahu’s power needs.
“We know that more solar power is possible on Oahu than was studied
by the OWIS. However, this baseline study is an essential first step for
the Interisland Wind Project. It shows that the technology may present
challenges but these can be overcome. The questions now are financing,
environmental impact and whether the effected communities can live with
the project with community benefits.”