How much more can nuclear power plants give?

EXECUTIVE SUMMARY In this age of rising electricity demand, people are trying to squeeze every last bit of power out of every power plant possible. Over the past few weeks, there’s been big news about nuclear power plants trying to do just that. Constellation, the largest nuclear operator in the US, announced plans to add nearly a gigawatt of new capacity across 11 existing nuclear reactors at six plants. And on October 5, the Department of Energy awarded a $4.2 billion loan to Vistra for previously announced upgrades at three plants. Pushing existing reactors to produce more could help provide more clean power for data centers, quickly. But just how much additional power can we count on?

执行摘要：在这个电力需求不断增长的时代，人们正试图从每一座发电厂中榨取每一分电力。在过去几周里，关于核电站试图实现这一目标的消息层出不穷。美国最大的核电运营商 Constellation 宣布计划在六座电厂的 11 个现有核反应堆中增加近 1 吉瓦的新产能。10 月 5 日，美国能源部向 Vistra 公司提供了 42 亿美元的贷款，用于其此前宣布的三座电厂的升级改造。推动现有反应堆提高产量可以帮助数据中心快速获得更多清洁能源。但我们究竟能指望增加多少电力呢？

Upgrading equipment at existing nuclear power plants can allow them to reach a higher capacity; the process is called a power uprate. Operators have been doing this since the 1970s in the US, but it’s been less common in recent years as demand for electricity plateaued and cheap natural gas put financial pressure on nuclear power plants. Some plants closed, and putting in more money to produce more electricity didn’t make much sense at others. Between 2001 and 2010, the US Nuclear Regulatory Commission approved over 80 uprates. Between 2011 and 2020, the number was 33.

升级现有核电站的设备可以使其达到更高的容量；这一过程被称为“功率提升”（power uprate）。自 20 世纪 70 年代以来，美国的运营商一直在进行此类操作，但近年来由于电力需求趋于平稳，且廉价天然气给核电站带来了财务压力，这种做法变得不那么普遍了。一些电厂关闭了，而对其他电厂投入更多资金以生产更多电力在当时看来并不划算。2001 年至 2010 年间，美国核管理委员会批准了 80 多项功率提升计划。而在 2011 年至 2020 年间，这一数字为 33 项。

But with the rise of AI and the related boom in electricity demand, there’s been a shift. We’re seeing shuttered plants like Palisades and Three Mile Island race to reopen. And existing plants are looking to uprate again. Some uprates are minor, involving changes to instrument setpoints or calculations at the plant. But more major overhauls, which can boost reactor power by as much as 20%, require replacing plant equipment. Generally, uprates involve using fuel that’s more highly enriched, or a higher volume of fresh fuel, in the nuclear reactor. That helps produce more steam, which is used to turn a turbine and generate electricity. To handle that additional energy, the main turbines and equipment such as pumps, motors, generators, and transformers are upgraded.

但随着人工智能的兴起以及由此带来的电力需求激增，情况发生了转变。我们看到像 Palisades 和三哩岛（Three Mile Island）这样曾经关闭的电厂正竞相重新开放。现有的电厂也正在寻求再次进行功率提升。一些提升幅度较小，仅涉及电厂仪表设定点或计算方式的调整。但更重大的改造（可将反应堆功率提高多达 20%）则需要更换电厂设备。通常，功率提升涉及在核反应堆中使用富集度更高或数量更多的新鲜燃料。这有助于产生更多的蒸汽，进而驱动涡轮机发电。为了处理这些额外的能量，主涡轮机以及泵、电机、发电机和变压器等设备都需要进行升级。

The most recent major uprate approved in the US was for three reactors at the Browns Ferry nuclear power plant in Alabama. A $475 million project saw that plant expand its power capacity by 14% between 2018 and 2019. Things could pick up soon, though. Constellation announced plans this week to spend more than $4.3 billion on uprates to 11 reactors. The additional electricity will be enough to power roughly 700,000 US homes. Behind it all? Big Tech money. Google agreed to buy electricity from these plants, and the 20-year agreement was a major factor in making the uprates happen. As Joe Dominguez, Constellation’s CEO, told the New York Times: “These are capital intensive, labor intensive projects that require a different price point than the market trades at, frankly.”

美国最近批准的一项重大功率提升项目是针对阿拉巴马州布朗斯费里（Browns Ferry）核电站的三座反应堆。该项目耗资 4.75 亿美元，使该电厂在 2018 年至 2019 年间将发电能力提高了 14%。不过，这种情况很快可能会加速。Constellation 本周宣布计划斥资超过 43 亿美元对 11 座反应堆进行功率提升。增加的电力将足以满足约 70 万户美国家庭的用电需求。这一切背后的推手是什么？是大型科技公司的资金。谷歌同意从这些电厂购买电力，这份为期 20 年的协议是促成此次功率提升的关键因素。正如 Constellation 首席执行官乔·多明格斯（Joe Dominguez）告诉《纽约时报》的那样：“坦率地说，这些都是资本密集型和劳动密集型项目，它们需要的价格点与市场交易价格不同。”

Also in the last few weeks, the US Department of Energy shared that it will commit over $4 billion to help finance upgrades and modernization for Vistra nuclear power plants across Pennsylvania and Ohio. Those projects will add 433 megawatts of power capacity, and Meta has already signed on to buy electricity from the plants in a long-term deal. A note about cost: On a per-kilowatt basis, that Constellation project is less expensive than building a new reactor, but it’s still more expensive than building a new utility-scale solar farm with energy storage or a combined-cycle natural-gas plant. Even at this high cost, uprates are in high demand.

同样在过去几周，美国能源部表示将投入超过 40 亿美元，用于资助宾夕法尼亚州和俄亥俄州 Vistra 核电站的升级和现代化改造。这些项目将增加 433 兆瓦的发电能力，Meta 公司已经签署了一项长期协议，购买这些电厂的电力。关于成本的说明：按每千瓦计算，Constellation 的项目比建造一座新反应堆要便宜，但仍然比建造一座配备储能设施的新型公用事业规模太阳能电站或联合循环天然气电厂要昂贵。尽管成本高昂，但功率提升的需求依然旺盛。

Today, the US nuclear fleet has roughly 98 gigawatts of total power capacity. Depending on who you ask, there’s somewhere between three and eight additional gigawatts on the table from uprates. A pretty significant chunk of the potential uprates in the US are already accounted for—the NRC already expects applications to add 2.4 gigawatts of power to reactors through 2032. It’s crucial to put these plans (and the total potential for uprates in the US) in perspective, though. PJM, the grid operator that covers much of the East Coast, expects about 30 gigawatts of additional peak demand because of AI by 2030. All the possible nationwide nuclear uprates would cover just a fraction of that.

目前，美国核电总装机容量约为 98 吉瓦。根据不同来源的估计，通过功率提升，还有 3 到 8 吉瓦的额外潜力。美国大部分潜在的功率提升项目已经有了着落——美国核管理委员会预计到 2032 年，通过反应堆功率提升申请增加的电力将达到 2.4 吉瓦。然而，必须客观地看待这些计划（以及美国功率提升的总潜力）。覆盖美国东海岸大部分地区的电网运营商 PJM 预计，到 2030 年，人工智能将带来约 30 吉瓦的额外峰值需求。全国所有可能的核电功率提升总量仅能覆盖其中的一小部分。

Making the most of existing nuclear reactors is a relatively easy win at a time when we need all the zero-emissions power we can get. But there’s still a lot of demand, and if we want more nuclear power to meet it, eventually that will require actually building new reactors. This article is from The Spark, MIT Technology Review’s weekly climate newsletter. To receive it in your inbox every Wednesday, sign up here.

在我们需要尽可能多地获取零排放电力的当下，充分利用现有的核反应堆是一个相对容易实现的胜利。但需求依然巨大，如果我们想要更多的核电来满足需求，最终将需要真正建造新的反应堆。本文摘自《麻省理工科技评论》的每周气候通讯《The Spark》。如需每周三在收件箱中接收，请点击此处注册。