Terra Praxis, a nonprofit focused on accelerating advanced nuclear deployment, has published a discussion paper called “REPOWER New York.” This post summarizes what the paper argues, what I found when I used Perplexity AI to check its numbers, and where I agree and disagree with its bottom line.
I am convinced that implementation of the Climate Leadership & Community Protection Act (Climate Act) net-zero mandates will do more harm than good if the future electric system relies only on wind, solar, and energy storage because of reliability and affordability risks. The opinions expressed in this article do not reflect the position of any of my previous employers or any other organization I have been associated with, these comments are mine alone. I acknowledge the use of Perplexity AI to research and organize the material summarized in this article.
What the paper argues
The core idea is straightforward: instead of building new nuclear plants one at a time as tailored, site-specific projects — which is how the U.S. nuclear industry has approached every reactor built in the last twenty years — New York should commit to a repeat-build program that puts the same reactor design on multiple sites in sequence. The paper argues the best sites are New York’s retired and at-risk fossil and industrial locations: former coal and oil plant sites and the state’s remaining single-unit nuclear plants, where transmission interconnections, water rights, and a trained workforce already exist. Reusing that infrastructure, the paper argues, avoids years of new transmission siting and permitting that a greenfield project would need.
The paper’s other central argument is about what it calls “Dispatchable Emissions-Free Resources,” or DEFRs — a term NYSERDA’s own Zero by 40 study uses for resources that produce no emissions, can be dispatched on demand, and can operate reliably through extended periods of low wind and solar output. The Zero by 40 study evaluated seven DEFR candidates: hydrogen combustion, renewable natural gas, advanced nuclear, carbon capture, geothermal, long-duration storage, and virtual power plants. The paper’s argument, and one that I have long also argued, is that nuclear is the only one of those seven that is commercially proven at scale, can be built to a firm schedule once a design is chosen, and does not depend on a fuel supply chain, storage duration breakthrough, or geologic accident of location the way the other six do. Hydrogen and RNG combustion depend on fuel volumes and delivery infrastructure that don’t yet exist at the needed scale. Geothermal in New York is site-limited. Long-duration storage and carbon capture are not commercially deployed at the scale this problem requires. Nuclear is the one DEFR you can actually plan to build, in a specific quantity, on a specific schedule, if you’re willing to pay for it and manage the program well.
That is the paper’s real argument, and it is the argument I want to spend the rest of this post on, because I think it is largely right, with one important caveat.
Where I agree: nuclear power is the DEFR you can develo as needed
New York’s own planning documents already say we need a lot more dispatchable, emissions-free capacity than we currently have. The Joint Utilities’ CGPP Cycle 1 Report filed with the PSC models a scenario with roughly 5.5 GW of nuclear-like DEFR capacity available by 2042 against a scenario without it, and finds the difference is stark: total system capacity of about 100,000 MW with that DEFR resource in the mix, versus about 130,000 MW without it, to serve the identical peak load. Put another way: every megawatt of firm, dispatchable capacity you don’t build gets replaced by roughly five to six megawatts of wind, solar, and storage nameplate capacity, because those resources aren’t available when you need them most. That 30,000 MW gap is the entire argument for DEFRs in one number, and it is New York’s own modeling, not Terra Praxis’s.
The Options Paper adds the piece that actually matters for a decision-maker: it prices out what that capacity costs to build. Under NYSERDA’s own analysis, a repeat-build fleet — its “Option 3: Multiple Sequential Pipeline Procurements” — carries an all-in price of roughly $12,800 to $13,400 per kilowatt in the Base Case, once the state provides financing support that gets private capital comfortable with the schedule risk. That is a real number I would not have expected NYSERDA to publish so plainly, and it is meaningfully lower than what the same paper shows for financing the same reactors with no state support at all — where the price nearly doubles, largely because private capital demands a much higher return to bear all the construction schedule risk itself. The point the paper is making, correctly, is that most of what makes nuclear expensive in the U.S. is not the reactor hardware. It is financing risk stacked on top of one-off procurement. That is consistent with what happened at Vogtle, where a program that started at roughly $14 billion for two units ended up above $30 billion, largely from schedule slip rather than design changes.
I have spent years arguing that New York’s decarbonization mandates keep underpricing the cost of firm capacity and overselling the reliability of wind and solar. If the state is serious about replacing fossil generation without wrecking reliability, a resource you can order in a known quantity, on a plannable schedule, at a knowable cost — using a design that has already been licensed and built elsewhere — is the only thing on that list of seven DEFRs that meets that bar today. I support developing enough nuclear capacity to cover the state’s baseload needs precisely because it is the viable alternative to the current plan, which is to keep building utility-scale wind and solar and hope storage and transmission catch up in time. They haven’t, and there’s no evidence in the state’s own filings that they will on the current timeline. A large, planned nuclear buildout is the one path I’ve seen that gets New York to a genuinely low-emissions grid without requiring tens of thousands of additional acres of utility-scale renewables and the transmission to move that power from where the wind blows to where the load is. Moreover, the cumulative environmental impact of that development is frightening.
Where I part ways with the paper: nuclear powr is a baseload solution, not an everything solution
Here is where I think the paper, and a lot of nuclear advocacy generally, overreaches. Nuclear is excellent at running flat out, all the time, for decades. That is exactly what baseload means, and it’s exactly why it’s the right tool for the DEFR problem: New York needs a large, firm floor of generation that doesn’t disappear when the wind stops or the sun sets. But the state’s electricity demand isn’t flat. There’s a large gap between the baseload floor and the peak load on the hottest afternoon of the summer, and that gap changes hour to hour and season to season. Nuclear plants are not economical, and are not designed, to ramp up and down to chase that kind of load — you don’t want a billion-dollar asset with decade-long payback economics cycling on and off to follow a few hours of afternoon peak demand a few dozen days a year.
That’s the role I think natural gas still should play, and I don’t think the paper’s framing — where the endgame is nuclear covering essentially all of the state’s electric energy — grapples with this. Peaking capacity and some intermediate load are jobs gas turbines already do well, at low capital cost, with fast start times, exactly because they only need to run a fraction of the year. Trying to cover that same peaking and intermediate role with more nuclear capacity means building reactors sized for the worst afternoon of the year and then running them well below capacity factor the rest of the time — which is the opposite of the economics that make repeat-build nuclear affordable in the first place. The paper’s own numbers show why: the value of a nuclear asset comes from running it as close to full output as possible for as many hours as possible. Ask it to load-follow like a gas peaker and you’ve thrown away the cost advantage the whole paper is built around.
Where I’d like to see more natural gas going forward isn’t in new electric generation, though — it’s in two other uses the paper doesn’t mention at all. The first is transportation combustion substitution: natural gas in place of diesel in trucks and other heavy vehicles does something wind, solar, and battery storage cannot do on any realistic timeline, which is cut inhalable particulate emissions from diesel exhaust at the tailpipe, immediately, in the communities where those trucks operate. That’s a real, measurable air-quality benefit — the kind I spent a career studying — and it doesn’t show up in the grid-decarbonization accounting either the state’s Energy Plan or this paper cares about, because it isn’t a grid benefit at all. The second is on-site use in homes and businesses, where high-efficiency gas furnaces and other direct-combustion appliances remain the cheapest and most energy-efficient option for space heating and process heat, out-performing electric-resistance and heat-pump alternatives on delivered cost and, in cold-climate operation, on efficiency as well. There is one other advantage of residential gas use – resiliency. I have lived in my home for 45 years and survived two major electric blackouts related to weather in no small part because natural gas provided heat, hot water, and cooking support during the multi-day electrical outage. I have never had a natural gas service outage.
A serious New York energy strategy should treat nuclear and gas as doing different jobs for different reasons: nuclear for the emissions-free baseload floor so we don’t have to keep chasing utility-scale renewable buildout, and gas for electric grid support, the transportation and on-site combustion roles where it beats the alternatives on cost, efficiency, or public health today. Trying to make nuclear substitute for those roles, or forcing electrification onto them by mandate, is asking one resource to solve problems it wasn’t built to solve, at a cost the repeat-build economics in this paper’s own tables were never meant to carry.
The fine print: what I’d flag on the numbers
I did not have time to check all the numbers in the report, so I used Perplexity AI for that purpose. With the caveat that I did not check all the Perplexity results I agree with the AI response that did not find anything fabricated in the paper — every figure checked traces back to a real NYSERDA filing, PSC proceeding, DOE study, or nuclear project cost record, and in most cases to the specific page or table cited. That’s a high bar for a 32-page advocacy paper with 94 endnotes to clear, and it did.
Bottom Line
New York’s own modeling says the state needs a large amount of dispatchable, emissions-free capacity that wind, solar, and storage cannot reliably provide, and nuclear is the only one of the seven DEFR candidates NYSERDA itself evaluated that is proven, buildable at scale, and priceable today. I support building enough nuclear power to cover the state’s baseload precisely because it is the one path that lets New York stop chasing an ever-larger buildout of utility-scale renewables and the transmission needed to move that power around. But baseload is not the whole grid, and it’s certainly not the whole energy economy.
Natural gas should still have a legitimate future role in peaking and intermediate generation that nuclear economics were never designed to serve. I believe that it is even more valuable to directly displace diesel in vehicle applications, where it cuts the inhalable particulate emissions that diesel exhaust puts directly into the air people breathe. In addition, I think natural gas provides on-site services cheaper and with better resiliency than electric alternatives so it should remain an acceptable option. A nuclear buildout that solves the baseload problem, alongside a gas fleet doing the jobs it’s actually good at, is a more honest — and more affordable — energy strategy than relying on wind, solar, and energy storage to provide electricity to do everything.
Pragmatic Environmentalist of New York 