Nome Power Integration Options
This project will focus on integrating wind and geothermal generation into the wind-diesel grid of Nome, Alaska. The potential need for an energy storage solution for grid stability is also explored.
Nome is an isolated community (no road access) located on the western coast of Alaska, just below the Arctic Circle. The electricity grid in Nome is an islanded microgrid (2.7 to 6 MW power levels) with no option to connect to a larger grid. The local wind farm capacity is 2.7 MW, and there is potential to add 2 MW of low temperature geothermal power to the energy mix. Currently, the wind farms fluctuations are buffered by diesel generation. However, the smaller diesel generators that would co-generate with a geothermal resource may be insufficient to provide the regulation services required to produce quality power. Energy storage solutions, e.g., flywheels and batteries, are explored as an alternative to replace the lost regulation services previously provided by larger diesel units. Using local generation, loads and meteorological data, different scenarios are simulated. The goal is to find the most economical and secure solution to meet power quality requirements while considering the current grid setup, and aspects of the local context including sub-arctic conditions.
The project goal is to provide Nome Joint Utility Services (NJUS) with data analysis, models, and additional information to support technical and economic decision-making process. The Power Systems Integration Program directly provides technical information to NJUS, and informs the Economic Analysis Group at ACEP of technical information relevant for economic modeling.
The first project phase is concerned with the interaction of energy resources (wind, geothermal, and diesel). The aim is to understand the impact of several generation scenarios on the overall amount of wind power that can be admitted to the grid, with risk of under-loading diesel generators. Since NJUS recently added additional wind resources, and smaller diesel gensets, existing historic data cannot be directly employed to drive a model. Statistical methods are employed to extrapolate wind power output from the extended wind farm. This data is fed into a time-series energy balance model (TSEBM). The TSEBM’s objective is to match energy generation with demand while considering the operational envelope of the diesel generators (scheduling and minimum and maximum optimal loading) and general grid stability. Information gained from TSEBM outputs will indicate the amount of wind power that cannot be admitted to the grid (spilled wind), and the optimal diesel-scheduling scheme based on current generation assets.
The second project phase will explore how energy storage solutions may be used to:
1) Ensure greater grid stability and power quality, should that be required.
2) Determine if an energy storage solution can economically reduce the use of diesel fuel by replacing the spinning reserve generally provided by a diesel generator.
Photo 1: Nome Windmill Installation. Courtesy of ACEP.
Photo 2: Street in City of Nome. Courtesy of ACEP.
Photo 3: Pilgrim Hot Springs. Courtesy of ACEP.