Climate Leadership and Community Protection Act and the NYISO Climate Change Impact Study

The New York Independent System Operator (NYISO) manages New York’s power grid and wholesale electric markets.   That responsibility not only includes the day-to-day management but also extends to long-term planning.  As part of the latter charge NYISO commissioned two studies of climate change impacts on power system reliability in New York.  These studies provide valuable insight into the scale of change necessary to implement the electric system transition necessary to meet the Climate Leadership and Community Protection Act (CLCPA) targets for emission reductions and renewable energy development.

NYISO 2020 10 08 Transmission IncreasesI am following the implementation of the Climate Act closely because its implementation affects my future as a New Yorker.  Various state entities are trying to choose between many expensive policy options to meet the CLCPA targets while at the same time attempting to understand which one (or what mix) will be the least expensive and have the fewest negative impacts on the existing system. If they make a good pick then state ratepayers spend the least amount of a lot of money, but if they get it wrong, then we will be left with lots of negative outcomes and even higher costs for a long time.  Given the cost impacts for other jurisdictions that have implemented renewable energy resources to meet targets at much less stringent levels, I am convinced that the costs in New York will be enormous and my analyses have supported that concern.  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.


In order to assess the potential impacts on power system reliability in 2040 associated with system changes due to climate change and policies to mitigate its effects, NYISO contracted with ITRON and the Analysis Group. Previously I described those reports and explained that I think further work is needed before we can be assured that solar and wind resources will be sufficient to meet load requirements.  Both studies also addressed the effects of New York’s CLCPA targets for decreasing greenhouse gas emissions, increasing renewable electricity production, improving energy efficiency and aggressive schedule that I have documented in CLCPA Summary Implementation Requirements

Itron developed long-term energy, peak, and hourly load projections that address the potential effect of climate change and the CLCPA. According to an Itron blog post that report identified “historical weather trends across more than 20 weather stations in New York State”. That information was used to drive system and planning area load models. They noted that “complicating factors include continued growth in behind-the-meter solar generation, increasing proliferation of electric vehicles and state policy to address climate change through electrification”.  The final report included two long-term hourly zonal-level load forecasts that reflect state policy goals and climate effects.

In the second phase the Analysis Group used the Itron load forecasts to evaluate system impacts and develop a plan to meet the CLCPA targets.  According to the Executive Summary in the draft Climate Change Phase II Study, it is “designed to review the potential impacts on power system reliability of the (1) the electricity demand projections for 2040 developed in the preceding Climate Change Phase I Study, and (2) potential impacts on system load and resource availability associated with the impact of climate change on the power system in New York (‘climate disruptions’).” The NYISO Electric System Planning Working Group meeting on September 10, 2020 included an overview summary presentation by the Analysis Group for the report.

Reliability Planning

On October 8, 2020 Kevin DePugh, Senior Manager for NYISO Reliability Planning, made a presentation to the Executive Committee of the New York State Reliability Council that emphasizes the results in the context of reliability planning.  The second phase report is supposed to consider potential effects of climate change and climate policy on the ability of the Bulk Power System to serve load and meet reserve requirements under a variety of conditions. However, the study is not an “extensive reliability study and will not include Resource Adequacy or Transmission Security”.

The modeling year is 2040 when all electric generation is required to be emissions free.  The generation resources estimate used the CLCPA resources announced to date as a starting point but resources were added to meet the load projections from Itron.  Itron accounted for climate change by assuming a 0.7 degrees F per decade increase in average New York state temperatures. In their reference case they made assumptions about energy efficiency and electric vehicle charging.   In their CLCPA case they assumed increases in energy efficiency, increases in electric vehicle charging load, and increases in residential and commercial building electrification to estimate the load in 2040.

The NYISO is evaluating four cases.  Itron developed a “Reference Case” and the “CLCPA Case” and the Analysis Group developed a set of electric generation resources to meet the needs of a reliable system in 2040.  NYISO’s Grid in Transition (GIT) study also produced two cases with different generation (notably including natural gas power plants) and transmission infrastructure resources.  Importantly, “Each case includes in the resource sets a generic resource, the role of which is to identify the attributes of any additional resources that may be needed to avoid or reduce Loss of Load Occurrences (LOLO)”. The report labels them as dispatchable and emissions-free resources (DE Resources).  Note that they “may include technologies under development or yet to be developed”.

The analysis considers the location of generation and the transmission needed to get that energy to where it is needed.  The GIT resource sets did not include any expansion of the Transmission System except for the two projects already on the books.  The Analysis Group cases included significant transmission increases to relieve 90% of transmission constraints”.

Hourly Load and Generation Balance

The presentation included a graph of the hourly load and generation balance for the winter wind lull physical disruption case.  (For a discussion of the Analysis Group physical disruption cases see my previous post.)  The graph shows the output from each generating resource against the predicted load for 30 days in the winter that includes a period of low wind resources.  While I don’t believe this is necessarily the worst case it does show a seven-day period when the projected nuclear, hydro, renewable resources, imports, price responsive demand and battery storage resources are insufficient to meet load demand.  In that period DE resources are needed to meet load.

The generation capacity resource mix for the climate change phase II (CCP2), CLCPA case is extraordinary.  Consider the changes from current levels for renewables.  At the end of 2019 the total New York State wind nameplate capacity was 1,985 MW but this case projects that 35,200 MW will be needed which is the National Renewable Energy Lab (NREL) projected total technical potential land-based capacity.  Governor Cuomo has announced offshore wind targets totaling 9,000 MW by 2035 but this case projects a need for 21,063 MW by 2040 which is another technical potential estimate limit.  There are 6,000 MW of solar by 2025 in the CLCPA targets but this projection estimates that 10,878 MW of behind-the-meter solar and 29,262 MW of grid connected solar will be needed.  New York’s target for energy storage is 3,000 megawatts deployed by 2030 and the case calls for 15,600 MW.  There is no specific goal for demand response but the plan calls for winter price responsive demand to equal 3,412 MW.  Even with all those mind-boggling projected capacities the DE resources capacity needed is 32,136.6 MW.

Dispatchable & Emissions Free Characteristics

Ultimately the problem is that no amount of additional renewable energy will provide electricity when the sun isn’t shining and the wind isn’t blowing.  In order to provide electrical energy during those periods NYISO has DE resources.  DePugh’s presentation lists the following characteristics of this resource:

      • Large quantity of DE Resource generation are needed in a small number of hours
      • DE Resource has low capacity factor (~12%) during the winter
      • DE Resource has only a 3.7% capacity factor in the summer
      • DE Resource is not needed at all during spring and fall
      • Substantial quantity of DE Resource capacity is needed, the energy need is minimal
      • DE Resource must be able to come on line quickly, and be flexible enough to meet rapid, steep ramping need
      • On an average day, storage can meet evening peaks, but the DE Resource must generate if storage is depleted and renewable generation is low
      • In the Winter CLCPA scenario, the DE Resource output across the state must increase from 362 MW (1.1% of DE Resource nameplate capacity) to27,434 MW (85.4% of name plate capacity) in six hours of the most stressed day

The Analysis Group and NYISO have not offered any examples of a resource that meets these characteristics.  In their presentation to the Power Generation Advisory Panel on September 16, 2020 Energy and Environmental Economics (E3) included a slide titled Electricity Supply – Firm Capacity that says: “As the share of intermittent resources like wind and solar grows substantially, some studies suggest that complementing with firm, zero emission resources, such as bioenergy, synthesized fuels such as hydrogen, hydropower, carbon capture and sequestration, and nuclear generation could provide a number of benefits”.    I believe the E3 firm, zero emission resource is the same as the NYISO DE resource so these are potential sources of dispatchable, emissions free energy.  E3 stated that: “New York can reliably meet growing electricity loads with 100% zero-emissions electricity by relying on a diverse mix of resources, including:

      • Onshore and offshore wind
      • Large-scale and distributed solar
      • In-state hydro and existing and new hydro imports from Quebec
      • Existing nuclear capacity
      • Existing and new combined cycles (CC) and combustion turbines (CT) utilizing zero-emissions biogas
      • New natural gas-fired combined cycles with carbon capture and sequestration (CC-CCS)”

I will leave a discussion of the likelihood of these resources for another time.


The DePugh presentation on the climate change studies makes the following observations (with my italicized comments).

      • Climate disruption scenarios involving storms and/or reductions in renewable resource output (e.g., due to wind lulls) can lead to loss of load occurrences. No comment.
      • The variability of meteorological conditions that govern the output from wind and solar resources presents a fundamental challenge to relying on those resources to meet electricity demand. As a result, it seems to me that a study specifically addresses this variability by looking at historical data is appropriate.
      • Battery storage resources help to fill in voids created by reduced output from renewable resources, but periods of reduced renewable generation rapidly deplete battery storage resource capabilities. Long-term energy storage is necessary for the transition but pumped storage hydro is the only proven technology available.
      • The DE resources needed to balance the system in many months must be significant in capacity, be able to come on line quickly, and be flexible enough to meet rapid, steep ramping needs. This is an instance where proven technology is unavailable.
      • The assumed increase in inter-zonal transfer capability in the CCP2 resource sets enables a renewables-heavy resource mix and improves reliability, but also increases vulnerability to certain climate disruption scenarios. I don’t worry as much about climate disruption affecting the transmission system as their concern that so much transmission will be needed that any weather-related interruptions will be a problem for the system.
      • Cross-seasonal differences in load and renewable generation could provide opportunities for renewable fuel production. I believe this is a suggestion that a wind and solar could be used to generate synthetic fuel in the shoulder months which is another unproven technology.
      • The current system is heavily dependent on existing fossil-fueled resources to maintain reliability, and eliminating these resources from the mix will require an unprecedented level of investment in new and replacement infrastructure, and/or the emergence of a zero-carbon fuel source for thermal generating resources. This conclusion should be the fundamental concern of everyone involved with CLCPA implementation.
      • Overall, the key reliability challenges identified in this study are associated with both how the resource mix evolves between now and 2040 in compliance with the CLCPA, and the impact of climate change on meteorological conditions and events that introduce additional reliability risks. This is another conclusion that should be at the forefront of those implementing the CLCPA even if the primary concern should be weather extremes not the tweaking effect of climate change in the next 20 years.
      • Comparing the CCP2 resource sets to the GIT resource sets reveals key differences in how the system makeup in 2040 can affect reliability outcomes. The differences are the result of the GIT resources using fossil-fired resources.


The CLCPA presumes that there is nothing aside from political will holding back implementation of an energy transition to clean, affordable, reliable, and resilient electric power by 2040.  However, the NYISO presentation says that eliminating existing fossil-fueled resources will “require an unprecedented level of investment in new and replacement infrastructure, and/or the emergence of a zero-carbon fuel source for thermal generating resources”.  It also notes that DE resources “include technologies under development or yet to be developed”.  The International Energy Agency recently published “Special Report on Clean Energy Innovation” that concludes that innovation is necessary for jurisdictions and companies to fulfill their de-carbonization targets.  Obviously, the CLCPA implementation plans should define a minimum acceptable technological readiness level for their recommended implementation strategies.

I don’t know what kind of reality slap will be needed to wake up those charged with developing the CLCPA scoping plan that the proposed energy transition is not simple or easy.  At the latest Climate Action Council meeting members were arguing that the CLCPA should not count bio-fuels as accepted renewables.  On the basis of these studies I think it is premature to reject any dispatchable emissions free resources, especially one that has some history of success.

Finally, note that the NYISO studies and the E3 pathways study do not mention cost or the expected lifetimes of the renewable technologies.


Author: rogercaiazza

I am a meteorologist (BS and MS degrees), was certified as a consulting meteorologist and have worked in the air quality industry for over 40 years. I author two blogs. Environmental staff in any industry have to be pragmatic balancing risks and benefits and ( reflects that outlook. The second blog addresses the New York State Reforming the Energy Vision initiative ( Any of my comments on the web or posts on my blogs are my opinion only. In no way do they reflect the position of any of my past employers or any company I was associated with.

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