In the last couple of years environmental advocates have vilified peaking power plants in their endless quest for zero risk to Environmental Justice (EJ) communities. There is no benign way to generate and distribute electricity so every option has drawbacks. I do not believe that the advocates understand that replacing a fossil-fired peaking power plant with their preference for “clean” energy and battery energy storage has risks that are potentially worse.
Everyone wants to do right by the environment to the extent that they can afford to and not be unduly burdened by the effects of environmental policies. This requires a pragmatic approach. The purpose of this blog is to describe the environmental tradeoffs associated with energy production and use in New York. I am motivated to write this article because I have been intimately involved with New York’s peaking power plants for a couple of decades. I believe the State’s policy appeasement of the environmental advocacy organizations is ill-founded and dangerous. 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.
Peaking Power Plants
Peaking power plants are used to balance generation and load. I recently described a paper that explains that electric load varies substantially: “Variations in demand profiles and the existence of demand peaks are caused by variation in weather, end-use technology stock, and, ultimately, consumer preferences and behavior”. Developing an electric system that reliably provides power for these demand peaks has always been part of the planning process for electric power systems. While on the face of it, for example as described in Wikipedia, the use of peaking power plants seems to be simple the reality is much different.
In 2020 the PEAK Coalition released a report entitled: “Dirty Energy, Big Money” that vilified peaking power plants in New York City. The PEAK coalition’s goal is to “come together to end the long-standing pollution burden from power plants on the city’s most climate-vulnerable people”. They claim their efforts are the first comprehensive effort in the US to reduce the negative and racially disproportionate health impacts of a city’s peaker plants by replacing them with renewable energy and storage solutions.
At the time I evaluated the technical analysis for the PEAK Coalition report by Physicians, Scientists, and Engineers (PSE) for Healthy Energy. I described my evaluation in three detailed technical posts. The first post provided information on the primary air quality problem associated with these facilities, the organizations behind the report, the State’s response to date, the underlying issue of environmental justice and addressed the motivation for the analysis. The second post addressed the rationale and feasibility of the Coalition’s proposed plan relative to environmental effects, affordability, and reliability. Finally, I discussed the Physicians, Scientists, and Engineers (PSE) for Healthy Energy report Opportunities for Replacing Peaker Plants with Energy Storage in New York State that provided technical information used by the PEAK Coalition. Because those were technically oriented and long, I also prepared a simpler summary post that addressed all my concerns.
I concluded that the claims that peaking power plants are dangers to neighboring environmental justice communities are based on emotion. In the evaluation I did of the PSE analysis and the PEAK Coalition report, I found that the alleged impacts of the existing peaking power plants over-estimates impact on local communities relative to other sources. The primary air quality health impacts claimed are associated with ozone and inhalable particulates that are secondary pollutants. While some inhalable particulates are emitted directly, most of the particulates and all of the ozone form after they are emitted and transported away from the disadvantaged communities peaking power plant closure is supposed to protect.
In my previous work I discussed feasibility challenges associated with the solar plus energy storage “solution” advocated by PSE and the PEAK Coalition. I believe that it will markedly increase costs significantly and it may not even work because solar and energy storage is not a proven technology on the scale necessary to provide New York City’s peaking power requirements. Until such time that the state’s organizations responsible for reliability confirm that those technologies are adequate it simply is not safe to rely on them. This post is going to address another pragmatic tradeoff – the relative potential environmental and health impacts of the so-called “zero-emissions” solar plus energy storage alternative.
New York Peaking Power Plant Environmental Policy
In order to address the peak load power requirements, New York utilities have relied on two types of generating resources: purpose-built units and existing but aging and inefficient units. The primary peaking power plant issue is in New York City where generating units are necessarily close to residential neighborhoods. Around 1970 Consolidated Edison of New York installed about 100 simple cycle combustion turbines to provide peaking power and also maintain reliability in specific regions of New York City and Long Island – known as load pockets. Load pockets represent transmission-constrained geographic areas where energy needs in that area can only be served by local generators, due to the inability to import energy over the transmission system during certain high-demand conditions. These units were cheap but not particularly efficient or clean. After de-regulation they were sold to several generating companies who considered replacement with efficient modern and clean units but despite the fact that permits to build replacements were approved no one ever built one. I believe this occurred because the developers did not think that they could recover the costs of building the replacements. I think that reflects the difficulty financing a facility that only operates infrequently.
However, the continued operation of the purpose built inefficient and dirty peaking turbines is coming to an end due to the New York Department of Environmental Conservation’s (DEC) “Peaker Rule”. The rule sets new limits on nitrogen oxides emissions from simple-cycle combustion turbines in a phased implementation from 2023 to 2025 that effectively forces them to install controls or be retired. Importantly, the rule included an electric system reliability subpart that ensured that the units would not retire until replacement power was available as determined by the “New York Independent System Operator (NYISO), the local transmission/distribution owner, or the New York State Public Service Commission”. This rule sets a good precedent for how electric generating units should be retired due to environmental policy.
The other source of peaking generation is older units that are no longer efficient enough to compete for normal operations. New York State has quite a few large steam boilers that were designed to burn residual oil. Over time the cost differential between oil and gas has shifted such that residual oil is rarely a cost-effective fuel to burn. Consequently, those steam boilers run very little and survive primarily to provide peaking power support. In addition, New York City has specific reliability requirements for in-city generation that mean that despite their low operating times those large steam boilers are paid for their ability to provide that service. The reliability requirements also mean that any replacement options for these facilities also have to be located in New York City.
At this time DEC is proposing guidance changes to the permitting process that will address the eventual retirement of these units to meet Climate Act mandates. It is worrisome that the lessons learned from the successful Peaker Rule don’t appear to be incorporated. Moreover, DEC is modifying its regulations for public participation in the Uniform Procedures Act apparently to appease the environmental advocates. I am convinced that the common theme in any public comments will be shut down the boilers and replace them with clean energy and battery energy storage without acknowledging the issues described in the next section.
Advocacy Replacement Proposal Issues
The crux of the problem is that environmental advocacy organizations and the PSE Opportunities for Replacing Peaker Plants with Energy Storage in New York State propose similar solutions for the purpose built turbines as the steam boilers. In 2019 the Department of Public Service released a report that studied the potential replacement of peaking units with energy storage that was adopted as proof that energy storage technology could be used for all the peaking power plants even though that report was concerned primarily with the peaking turbines. The PSE report did not differentiate between small peaking turbines and much larger steam boilers. In addition to the local air quality impact concerns, the Climate Leadership and Community Protection Act includes a mandate to make the electric grid zero-emissions by 2040. As a result, environmental advocacy groups are lobbying hard to shut down any remaining units, including the steam boilers, that operate infrequently enough to be classified as peaking units. Their plan is to phase out fossil fuel peaker power plants and replace them with clean renewables and battery energy storage system (BESS) technologies.
I believe PSE has misled the advocacy groups that their control alternative is a viable option for large boilers. There are two problems with large boiler replacement. The first is the size of the boilers. The following table lists the remaining New York City steam electric boiler units. They are all old and some run under 5% of the time. Next year the majority of the operating (Title V) permits for the boilers will expire. In New York City, the smallest boiler is 146 MW, there is a total of 2,095 MW of boilers that operated less than 5% of the time in 2021 a total of 3,555 MW of boilers whose operating permits expire next year, and total of 3,887 MW of steam boiler capacity in New York City. The cost of replacing that amount of capability will be very high at a time of increasing energy costs.
New York City Steam-Electric Boilers
The second boiler replacement problem is the space necessary for a battery array that can provide the energy equivalent to any of the electric-steam boilers still operating in New York City. I was unable to find spatial requirements on the web so I base my estimates on the Elkhorn Battery facility at Moss Landing in California. Elkhorn Battery consists of a total of 256 Tesla Megapacks, the total energy capacity is 730 MWh, and power output is up to 182.5 MW, As shown in the following view there are 132 cubical structures that apparently hold two Megapacks each. I estimate that one third (in the 4 by 11 configuration) of the Megapacks are rated at 60.8 MW and produce 243 MWh cover an area of 240 by 280 feet which works out to around 1.5 acres.
Google Maps view of the Elkhorn Battery array at Moss Landing, California
Using that estimate of spatial requirements I estimated the New York City acreage necessary to replace steam electric boilers with the clean energy and battery storage option. Replacing the smallest boiler would require 3.6 acres. Replacing the 2,095 MW of boilers that operated less than 5% of the time in 2021 would require 52 acres. Replacing the total of 3,555 MW of boilers whose operating permits expire next year would require 88 acres. Finally, replacing all the steam boiler capacity in New York City would require 95.9 acres. Space in New York City is at a premium so the area needed may not be available.
One other point is that these spatial estimates are based on power (MW) capabilities. At this time battery energy storage systems only provide energy for four hours. Because peak load requirements can be greater than four hours and these steam boilers can run throughout a load peak, the number of batteries necessary to provide that energy is significantly greater than shown here. I believe that when the full energy requirements necessary to replace the steam boilers is calculated it will be determined that there is insufficient room available in New York City to provide equivalent capabilities.
Energy Storage System Environmental Risks
In addition to logistical implementation issues, there are environmental tradeoffs and safety risks. The Tesla Megapack lithium-ion batteries are similar to the ones in electric vehicles. Michael Mills explains that there is no such thing as a “zero-emissions” vehicle. He points out that you don’t eliminate emissions you export them. This also applies to BESS components but I am not going to discuss this hypocrisy anymore in this post.
Instead, I am going to focus on the potential risks of BESS thermal runaway fires and explosions. Paul Christensen, Professor of Pure and Applied Electrochemistry at Newcastle University in the United Kingdom gave a presentation at PV magazine’s Insight Australia event in 2021 that describes the risks. He is one of the world’s leading experts on battery fires and safety and said global uptake of lithium-ion battery technology has “outstripped” our knowledge of the risks. I recommend the entire presentation as a good overview of this issue.
His primary concern about battery fires is described in the presentation. Once a battery is abused the chemistry can become unstable. If it does that generates gases and heat, the heat creates more gases and the potential exists for a thermal runaway reaction. The following slide illustrates the relationship.
Christensen explains that:
In thermal runaway and prior to ignition, lithium- ion batteries produce a white vapour which consists of: hydrogen (ca. 30-50%), carbon monoxide, carbon dioxide, hydrogen fluoride, hydrogen chloride, hydrogen cyanide, small droplets of the organic solvents, ethane, methane and other hydrocarbons, sulphur dioxide and nitrogen oxides, i.e. a vapour cloud.
He explains that thermal runaway runaways should be prevented by safety systems, but he points out that fires and explosions are still occurring on land, sea, and in the air. His presentation included the following slide that lists Lithium Ion Battery Energy Storage System (LiBESS) events. The acronym VCE stands for vapor cloud explosion on the list. Also note that since the presentation, the Moss Landing facility had another fire incident on September 20, 2022 that shut down traffic and resulted in a shelter in place advisory.
Christensen explained that the Korean government is leading the world in LiBESS developments and the presentation included a description of a translation of the official South Korean government report on LiBESS fires:
It is likely that these safety flaws are not unique to battery systems and BESS made in Korea. It is more likely that the large amount of BESS installed in Korea has made the flaws evident earlier. These flaws are also likely to exist in BESS and battery systems that were not made by Korean manufacturers.
BESS safety can only be fully assessed on the system level. A safe battery cell is the foundation for a safe BESS, but not a guarantee. The historical strong focus on cell safety only has led to avoidable slips in the technical risk management of BESS projects as a whole. Therefore, the safety assessment of the BESS should cover all hazards, not just the electrochemical related hazards.
The LG Chem report on SK incidents blames:
- Inadequate design of the electrical protection system
- Inadequate control of the operating environment within system enclosures
- Careless installation practices that degraded system integrity
- Inadequate ESS system control and protection
Failures could only be reproduced with multiple stresses, e.g.: High humidity + Common Mode Voltage (CMV) aka Common Mode Noise.
Christensen describes the characteristics of the thermal runaway plume and then he shows frightening examples of tests of vapor cloud fires and explosions. The intensity of the fires and the toxic gases mean that fire fighters cannot put the fires out safely. They just have to let them burn themselves out and hope that the fires don’t destroy anything other than the batteries and their enclosures.
The peaking power plant issue is a poster child example of the dangers of environmental advocacy organizations misplaced focus on one issue. Disparaging ugly peaking power plants in neighborhoods makes for a great sound bite rallying call to stir up action. However, the argument that those facilities are the root cause of significant health issues rings hollow because the primary air quality effects are from secondary pollutants that form after the emitted pollution has been transported away from the neighborhood. Moreover, my bet if an air quality monitoring attribution analysis was done in the so-called “asthma alley” that advocates mention in their press releases, is that fossil-fired power plants would not be the dominant component.
Nonetheless, the Hochul Administration is pushing for closure of power plants in New York City. According to the LS Power website:
On October 17, 2019, the PSC granted a Certificate of Public Convenience and Necessity (CPCN) for LS Power’s proposed 316-megawatt battery energy storage project at the Ravenswood Generating Station in Long Island City. Additionally, the Ravenswood storage project was accepted in the New York Independent System Operator (NYISO) 2019 interconnection facility study process, and is therefore well positioned to be able to meet a 2022 in-service requirement.
A trade press article about the Ravenswood renewable redevelopment plans states:
Energy asset developer Rise Light & Power will redevelop its 2,480MW Ravenswood Generating Station – New York City’s biggest power plant – as a new renewable energy hub including on-site energy storage.
The 27-acre site in Queens will be turned into a hub integrating various clean energy sources, although the press release is not clear on when the fossil fuel units will be retired nor exactly what renewable capacity will be built on-site.
It does make clear that large-scale battery energy storage will be deployed directly on the facility site, which currently powers 20% of New York City’s needs.
The redevelopment will repurpose existing infrastructure to connect thousands of megawatts of offshore wind and onshore wind, solar, and other clean energy resources from Upstate New York to the City’s grid, a press release said. Ravenswood’s river water intake system will also be repurposed to provide zero-emission thermal energy to nearby communities.
LS Power is proposing a 316 MW BESS on a 27-acre site in New York City. According to my estimates that requires 7.8 acres for equivalent battery energy storage. I could not find any details of the proposed plan but they necessarily must pack the batteries closer together than the battery array at the Elkhorn Battery in Moss Landing, CA. Given that facility has had two fires since it began operating a little over a year ago and the Christensen presentation shows how dangerous those fires can be, my impression that is not such a good idea. Dr. Christensen’s remark that he is “astounded and appalled that if there is no appreciation of the safety issues involved” certainly should prompt an extensive safety review before this facility is permitted and constructed.
I conclude that until you have a viable alternative, and I submit that the renewable energy battery storage option is not viable, then it is premature to shut down the existing fossil fired peaking generation in New York City and the state. Not only will the closures have minimal effect on health impacts but closure could affect reliability. Given the impacts of New York City blackouts I don’t believe any threats to current reliability standards should be accepted.
Furthermore, the proposed alternative of renewable energy and energy storage systems has to overcome space constraint issues and is not proven technology. When a leading expert on batteries says “Everybody has to be educated how to use these batteries safely”, I think the best course of action is to follow his advice. It is not appropriate to make the residents of the disadvantage communities near a BESS become unwilling lab rats to test whether a technology that can generate toxic gases, fires, and explosions is appropriate in an urban setting.
Another unrecognized constraint by the environmental advocacy organizations is the financing model for a necessary resource that only operates a few times a year. Purpose-built peaking generation resources to this point have relied on the cheapest resource available such as simple-cycle combustion turbines. While an argument may be made that some renewable generation resources are competitive with simple cycle turbines the requirement in New York City is for a dedicated resource capable of providing peaking power on demand. That means that the renewable resources, the transmission to get that power to New York City, and the BESS to provide that power have to be dedicated to this requirement. I believe those costs will be several multiples greater than any fossil-fired alternative so financing and operation costs will be a problem.
Of course, the environmental advocate argument is that it is necessary to address climate change. Paraphrasing Tom Shepstone, my ultimate concern is “It is profound climate misinformation to suppose global warming is such a threat that any action, no matter how risky, is somehow preferable to a fossil fuel alternative without those risks”.