Scoping Plan Renewable Energy Resource Availability Analysis

New York’s Climate Leadership and Community Protection Act (Climate Act) has a legal mandate for New York State greenhouse gas emissions to meet the ambitious net-zero goal by 2050. The Climate Action Council is responsible for preparing the Scoping Plan that will “achieve the State’s bold clean energy and climate agenda”.  This post describes comments I submitted to the Council about the inadequate analyses of renewable energy resources in New York.  It is important to get this right because the availability of renewable energy resources informs the basis of resource adequacy planning.

I have written extensively on implementation of the Climate Act because I believe the ambitions for a zero-emissions economy outstrip available renewable technology such that it will adversely affect reliability and affordability, risk safety, affect lifestyles, will have worse impacts on the environment than the purported effects of climate change in New York, and cannot measurably affect global warming when implemented.   The opinions expressed in this post do not reflect the position of any of my previous employers or any other company I have been associated with, these comments are mine alone.

Climate Act Background

The Climate Act establishes a “Net Zero” target by 2050. The Climate Act requires the Climate Action Council to “[e]valuate, using the best available economic models, emission estimation techniques and other scientific methods, the total potential costs and potential economic and non-economic benefits of the plan for reducing greenhouse gases, and make such evaluation publicly available” in the Scoping Plan.  The integration analysis developed by the New York State Energy Research and Development Authority (NYSERDA) and its consultants was used to develop the Draft Scoping Plan that was released for public comment on December 30, 2021. The Scoping Plan has to be finalized by the end of 2022 and a recent meeting discussed issues that need to be addressed to meet that schedule.

New York’s unprecedented transition to a zero-emission electric generating system means that the system will be heavily dependent upon wind and solar resources.   Because those resources are intermittent it is imperative that New York energy planning determine the frequency and duration of periods when wind and solar resources are low.  This article summarizes comments that I submitted on the problem, describes analyses that address this issue completed elsewhere, and recommends that New York agencies develop an appropriate study centered on New York.

Problem

The comments included a description of New York blackouts and the responses made to prevent reoccurrences.  I believe that, despite the best efforts of those responsible for the reliability of the electric grid, the transition to an electric power system that relies on intermittent wind and solar resources introduces so many changes that it will be impossible to anticipate them all.  As a result, grid resilience will decrease and blackouts are inevitable.   For example, consider that a team of researchers from the University of Nottingham recently addressed the effect of renewable energy resources on power grid stability.  The abstract from the paper states:

Contemporary proliferation of renewable power generation is causing an overhaul in the topology, composition, and dynamics of electrical grids. These low-output, intermittent generators are widely distributed throughout the grid, including at the household level. It is critical for the function of modern power infrastructure to understand how this increasingly distributed layout affects network stability and resilience. This paper uses dynamical models, household power consumption, and photovoltaic generation data to show how these characteristics vary with the level of distribution. It is shown that resilience exhibits daily oscillations as the grid’s effective structure and the power demand fluctuate. This can lead to a substantial decrease in grid resilience, explained by periods of highly clustered generator output. Moreover, the addition of batteries, while enabling consumer self-sufficiency, fails to ameliorate these problems. The methodology identifies a grid’s susceptibility to disruption resulting from its network structure and modes of operation.

My comments included a description of the Texas blackout of February 2021.  Ultimately the reason for the blackout was poor planning.  When the people of Texas needed electric power the most the generating resources available were unable to meet those needs.  In order to prevent the same thing from happening in New York it is necessary to provide sufficient energy at all times.

Reliability planning in the past relied on dispatchable generating resources.  The Climate Act future electric generating system will rely on intermittent renewable wind and solar that is not dispatchable.  Energy storage resources are needed to cover periods when wind and sun energy is not available to provide dispatchable electricity.  The problem is that we have to know what the worst-case renewable resource availability is in order to size the energy storage resources correctly.

Last year I described issues related to this as the Climate Act’s ultimate problem. Although there have been analyses that have identified winter wind lull periods are a problem, I do not believe that they addressed this analysis correctly because they used relative short periods as the basis for their projections.  As far as I can tell the Integration Analysis did not even consider the same period for wind and solar resources in their analysis.  As a result, I believe the Draft Scoping Plan projections for the amount of resources during these periods is incorrect.

Proposed Analysis

In order to do this right, the critical consideration is the frequency, duration, and severity of periods when wind and solar resources are in “droughts” or low resource availability.  I described several recent applicable papers that estimate the frequency and duration of periods with those conditions using a meteorological reanalysis data base.  In this approach historical observations are re-analyzed using current weather forecast models.  The first step in developing a weather forecast is to incorporate meteorological observations to setup the weather maps that are the starting point for weather forecast calculations.  That component of the models is used to develop weather maps for the observations and the forecast component is used to provide hourly data until the net observation period.

In order to provide a robust estimate of the wind and solar availability during worst case conditions it is necessary to analyze as long a time period of historical meteorological data as possible. The ERA5 global reanalysis data base generated using this reanalysis technique provides hourly estimates of a large number of atmospheric, land and oceanic climate variables. The data cover the Earth on a 30km grid and resolve the atmosphere using 137 levels from the surface up to a height of 80km. That information is then used to estimate the availability of hourly wind and solar resources for any area of the globe.

Last fall I described a paper that included an approach that might work for an analysis centered on New York.  Since then, I have been in touch with the author and I am not confident that using these data would be provide invaluable information. 

In my comments I strongly recommended an analysis in New York using the complete (1950 to present) ERA5 meteorological database to determine the frequency and duration of renewable resource droughts in order to estimate the appropriate worst case.  The goal of the project would be three-fold:

• Determine historical intensity, frequency, duration and seasonality of wind and solar droughts in New York;
• Identify co-occurrence of wind and solar droughts with high demand periods (heating/cooling degree days); and
• Interpret the droughts and high demand periods: seasonal, weather regimes, interannual variability (e.g. El Niño-Southern Oscillation), multi-decadal climate regimes, and trend associated with global warming

Conclusion

I have submitted comments in various proceedings and have tried to work behind the scenes to get this analysis completed because I don’t think it is possible to adequately project the renewable resources necessary to keep the lights on when needed most without this information.  I submitted these comments to get on the record again that this work has to be done to ensure that sufficient renewable energy generation and energy storage is developed to prevent blackouts.