Integrating wind and wave power in California [electronic resource]

California is increasing the percentage of its electrical energy supply from renewable energy resources. The motivation to shift from fossil fuel fired electric power plants to renewables is to mitigate the health and environmental consequences of combusting fossil fuels. The primary challenge to supplying the demand for electricity with renewables is the variable and uncertain generation of electric power from renewable energy resources. This dissertation focuses on the contribution of renewable resources themselves to mitigate their own variability and uncertainty through the synergistic combination of co-located offshore wind and wave energy and the quantification of specific time of day impacts of wind power to the California electric power system. Large untapped renewable energy resources of offshore wind and wave energy exist for California to meet its renewable energy goals, and these resources are quantified as time series of electric power production to further explore their benefits. Existing grid integration methodologies are, for the first time, extended to combined offshore wind and wave energy farms in the U.S. and the benefits of co-locating offshore wind turbines and wave energy devices are quantified. The primary benefits of combining offshore wind and wave energy identified are: (1) a reduction in the hours of no power output and a resulting increase in the capacity value of the combined farms to the electric power system; (2) a reduction in the hourly variability of power output which reduces the operating reserve requirement to manage variable power output from renewables; (3) a reduction in transmission capacity required to interconnect an offshore farm which reduces capital costs and creates a farm with a more consistent power output over a smaller range. The variability and uncertainty of onshore wind power are quantified for the California power system when it builds the projected wind capacity to meet its 33% Renewable Portfolio Standard by 2020. The variability and uncertainty are combined with the existing variability and uncertainty in the demand for electric power to identify the net, if any, increase in the system variability and uncertainty that would require additional resources to balance the system given rapid changes (variability) and forecast errors in demand, generation, and transmission (uncertainty). The analysis included a diurnal examination of the variability and uncertainty that more accurately reflects the characteristics of the thermal wind regimes of California. The key results were (1) the California system should see no net increase in variability from that already present in the system; (2) the system will see more, but not greater variability, during the afternoon hours from the pattern of California wind power output; (3) the forecast error will increase for the California system over current forecast errors with the addition of wind power that will require additional resources like operating reserve to manage the large errors, but (4) the daily cycle of these greater forecast errors mitigates some of the challenges they may present because of the state of the power system and the generators online when these errors occur.

Advisor: Jacobson Mark Z. (Mark Zachary) primary advisor. Thesis advisor
Rajagopal Ram advisor. Thesis advisor
Weyant John P. (John Peter) advisor. Thesis advisor