The electric utility industry is undergoing a transformation from the traditional utility model (operating large base load power stations and supplying electricity to a captive customer base) to one that faces challenges due to increasing customer choice, cheap natural gas, falling prices for renewables and energy storage, and the need for grid resiliency to withstand major power interruptions from extreme weather. This transformation is not only occurring within the industry business model, but is impacting our specific day to day roles and responsibilities within our specific jobs. The role of the electric utility meteorologist is undergoing a transformation as well, with increasing opportunities to improve coordination of meteorological forecasts and content to inform and improve operating efficiencies across the electric enterprise as the industry transforms itself.
In the traditional electric utility model, the role of the meteorologist served three basic business needs. These were centered around supporting generation dispatch and power trading, severe weather forecasting support for emergency planning and resource modeling, and providing regulatory and dispersion modeling support for nuclear and fossil power generating stations. While these roles will continue to remain the key job requirements for utility meteorologists, the transformation of the electric utility model due to the increasing penetration of renewable energy sources will continue. The need for grid modernization with increasing customer focus will require utility meteorologist to redefine their day to day job functions to better coordinate the information flow from the meteorologist’s desk to the operations centers across the enterprise.
The impact of weather forecast information on power generation and system optimization is substantial. Electric utilities base their daily economic generation stack on the forecast system electric demand, which depends on the weather forecasts of hourly temperature, dew point, clouds, and increasingly the amount of available solar irradiance and wind resources. On a typical day, the meteorologist inputs the weather forecast into a load demand model that projects the hourly electric load in some cases past a week. Generation units are dispatched with the lowest cost units dispatched first. The sensitivity in generation load to the weather forecast can be as much as several hundred MW of electric demand for each 1 degree of temperature error, based on the system size and time of year.
With the increased penetration of solar generation on the grid, the meteorologists are now called upon to integrate the solar irradiance forecast into the electric demand load equations for same day economic optimization of the generation stack. The solar forecast is also used to calculate the day ahead reserve margins that a balancing authority is required to carry for bulk electric grid reliability. The role of the meteorologist in production of the daily electric demand forecast based on weather forecast inputs and increasing solar penetration becomes even more critical to enhanced optimization of the generation resources. One area of increased coordination between the utility meteorologist and generation dispatch and power trading, is to provide uncertainty forecasts for risk based decisions to operators that are accustomed to deterministic delivered forecasts. This is becoming increasingly important in the area of solar forecasts, where the uncertainties are even greater due to the limited performance of irradiance forecasts from the available forecast models. Meteorologists can utilize their statistical background and forecast expertise to develop confidence limits in the irradiance forecasts, to better bracket the same day and day ahead forecasts of solar generation expected on the balancing authority grid, and improve optimization decisions for the daily generation stack. Additionally, as battery storage utilization plays a greater role as our power grid becomes smarter, meteorologists can utilize their knowledge to communicate to grid operators when the potential of power outages due to severe weather may occur. They can also provide forecasts down to the micro-grid scale that enhance the ability of grid operators to manage battery storage systems with optimal settings.
As we have seen recently with Hurricanes Harvey, Irma and Maria, wildfires in the western US, and daily severe weather outbreaks, the need for electric utility operators to better integrate a risk based approach of weather forecasts into their daily operational decisions is becoming increasingly important; it is expected by customers, utility commissions, and regulators. Meteorologists can aid in improving the coordination of business operations and communicating risk within the emergency planning organizations to improve resiliency to extreme weather impacts on grid operations, generation facilities, and customer communications. Developing outage prediction tools and running pre-storm resource models to develop a probabilistic approach to expected and worst-case weather impacts across the utility enterprise are an increasing need in the industry. Better communication of potential extreme weather impacts by the meteorologist can save utilities millions of dollars in improved pre-storm response planning across all organizations with the goal of reducing customer power outage times and mitigating damage to utility generation and infrastructure. Meteorologists have an important role in the integration of science into informed operational decisions for pre-storm emergency planning.
The transformation of any business model or sector of the economy can be disruptive and stressful. The transformation we are seeing in the energy sector is coming fast, due to the increasing demand for cleaner energy, the need for improved grid resiliency and reliability, and the reality of lower customer growth. All present both challenges and opportunities. As with any industry transformation, the transformative requirements are not limited to the business model, but encompass our professional job functions. Meteorologists are uniquely equipped to integrate the science of meteorology into better electric utility operational decisions, as the traditional utility model undergoes change.
Nick Keener, Director of Meteorology
Duke Energy