Uncertainty around high wind and solar penetration has been weighed, measured, and found wanting…autoDR and storage

Uncertainty surrounding fossil fuel prices, increased regulations on fossil fuel emissions, and a growing desire for energy independence and cleaner power are pushing governments to look to renewables to appease the masses. Although the emergence of modern wind and solar technologies promise to satiate government-mandated need for large-scale renewables, resources depending directly on the wind and sun for their fuel bring with them the same uncertainty as the evening news weatherman. With wind and solar electricity mandated to jump from 1.5% to 11% of electricity generation capacity globally before 2050, grid operators are faced with the unique challenge of being required to guarantee 100% reliability (client registration required) while being compelled to incorporate an increasing proportion of inherently unreliable renewable electricity generation resources. This task may seem straightforward because at first glance the daily and seasonal profiles of wind and solar generation appear to complement one another to meet demand. Upon closer inspection, however, power output from wind and solar resources fluctuates in its frequency, magnitude, duration, and speed, and varies further over timescales of seconds, minutes, hours, days, and months. Grid operators that have turned to natural gas peaker plants in the past will need to incorporate emerging technologies such as automated demand response (autoDR) (client registration required) and grid storage to fill in the generation gaps, but have yet to fully quantify how much of the intermittency these new resources can manage and at what cost.

We have evaluated and quantified the impact of various levels of wind and solar penetration to determine the amount, if any, of autoDR and energy storage that can and should be used to mitigate the impacts of these inherently unpredictable energy supplies in ways that existing and new natural gas capacity cannot. We have determined that at 30% renewable energy penetration, 2% of the highest peak daytime demand can be shifted to the night by autoDR and 0.5% of the annual electricity generated must be stored and shifted to minimize the curtailment of wind resources (see the full analysis in the report “Cloudy with a Chance of Energy: Evaluating Technologies to Manage Grid Intermittency” — client registration required).