A Startup Wants to Power Data Centers With ‘Supercritical’ Carbon Dioxide
A Startup Wants to Power Data Centers With ‘Supercritical’ Carbon Dioxide
一家初创公司计划利用“超临界”二氧化碳为数据中心供电
A new company has a plan to make the dirty gas turbines powering data centers more efficient: liquid carbon dioxide. American Supercritical came out of stealth Wednesday, announcing $8 million in funding. It wants to retrofit inefficient gas turbines that many data centers rely on for power with units that can generate more power, without adding more emissions (though the gas-fired turbines will continue to emit carbon pollution). The technology can also theoretically be used on a wide variety of energy sources at a time when power demand is skyrocketing. “We want to start with gas turbines but eventually expand beyond that,” says cofounder Simon Shuham.
一家新公司计划通过液态二氧化碳，提高为数据中心供电的“脏”燃气轮机的效率。American Supercritical 公司周三结束隐身状态，宣布获得 800 万美元融资。该公司希望对许多数据中心所依赖的高能耗燃气轮机进行改造，加装能够产生更多电力的装置，且不会增加额外排放（尽管燃气轮机本身仍会排放碳污染物）。在电力需求激增的当下，该技术理论上还可应用于多种能源。联合创始人 Simon Shuham 表示：“我们想从燃气轮机开始，但最终会扩展到其他领域。”
Most large gas-fired power plants in the United States use an array of heat engines in what’s known as a combined-cycle process: First, turbines generate electricity from burning compressed air and natural gas, then a separate engine uses the hot exhaust to make steam and create additional energy. But for a variety of reasons, data centers across the US have opted to power their operations with what are known as simple-cycle turbines, and exclude the steam component.
美国大多数大型燃气发电厂使用一系列热机，采用所谓的“联合循环”工艺：首先，涡轮机通过燃烧压缩空气和天然气发电，然后由另一台发动机利用高温废气产生蒸汽，从而创造额外的能量。然而，由于各种原因，美国各地的数据中心选择使用所谓的“简单循环”涡轮机来为其运营供电，并排除了蒸汽循环部分。
These turbines are much less efficient than combined-cycle plants. Usually, only about 35 percent of the energy from simple-cycle turbines is converted to electricity, while the rest escapes as exhaust. (In combined-cycle plants, that figure hovers closer to 60 to 65 percent.) That exhaust includes greenhouse gases, making plants that run on simple-cycle turbines a much worse choice for the environment than combined-cycle plants.
这些涡轮机的效率远低于联合循环电厂。通常，简单循环涡轮机中只有约 35% 的能量转化为电能，其余部分则作为废气流失。（在联合循环电厂中，这一比例接近 60% 到 65%。）这些废气中含有温室气体，使得运行简单循环涡轮机的电厂对环境的影响远比联合循环电厂严重。
The size of some of these plants combined with their inefficiency is a recipe for climate disaster. A massive data-center power plant in Texas that Amazon is building with just simple-cycle turbines, for instance, is permitted to emit more than 33 million tons of greenhouse gases per year—more than the annual total of some small countries.
其中一些电厂的规模加上其低效性，简直是气候灾难的温床。例如，亚马逊在德克萨斯州正在建设的一座仅使用简单循环涡轮机的大型数据中心发电厂，其获准每年排放超过 3300 万吨温室气体——这比一些小国家的年度排放总量还要多。
But all these small, inefficient turbines could be a great match for supercritical CO2 technology, American Supercritical’s founders say. Carbon dioxide becomes supercritical when it’s pressurized and held at a certain temperature. In this state, it gets the density of liquid but still behaves like a gas, meaning it can move energy more efficiently through much smaller amounts of equipment.
但 American Supercritical 的创始人表示，所有这些小型、低效的涡轮机可能与超临界二氧化碳技术非常契合。二氧化碳在加压并保持在特定温度下时会变成“超临界”状态。在这种状态下，它既具有液体的密度，又表现得像气体，这意味着它可以通过更小型的设备更高效地传输能量。
American Supercritical wants to attach its units to small gas turbines and help generate more energy. While the turbines themselves would still use gas, the supercritical CO2 unit can use the hot exhaust generated from those turbines to create additional electricity. Instead of using that heat to boil water and create steam, the heat is transferred directly by the pressurized CO2 to generate additional energy with no additional emissions. “We’re essentially building miniature combined-cycle plants,” says Shuham.
American Supercritical 希望将其装置安装在小型燃气轮机上以帮助产生更多能源。虽然涡轮机本身仍使用天然气，但超临界二氧化碳装置可以利用这些涡轮机产生的高温废气来制造额外的电力。该技术不再利用热量烧水产生蒸汽，而是通过加压的二氧化碳直接传递热量，从而在不增加额外排放的情况下产生额外能量。Shuham 说：“我们本质上是在建造微型联合循环电厂。”
Using supercritical CO2 also can eliminate or greatly reduce water use in the power generation process—something that’s drawn intense scrutiny when it comes to data centers. Importantly, the CO2 involved operates in a closed-loop system, meaning that it doesn’t have to be refilled. Cofounder Matthew Carlson, who researched supercritical CO2 for more than a decade, likens it to refrigeration systems that circulate CO2 to facilitate cooling.
使用超临界二氧化碳还可以消除或大幅减少发电过程中的用水量——这在数据中心领域一直受到密切关注。重要的是，所涉及的二氧化碳在闭环系统中运行，这意味着无需补充。联合创始人 Matthew Carlson 研究超临界二氧化碳已超过十年，他将其比作通过循环二氧化碳来辅助冷却的制冷系统。
The company plans to initially sell a 10-megawatt unit—relatively small by gas plant standards. By American Supercritical’s math, adding supercritical CO2 units could increase turbines’ efficiency by up to 50 percent without adding any more greenhouse gas emissions or water use.
该公司计划初期销售 10 兆瓦的装置，按燃气电厂的标准来看相对较小。根据 American Supercritical 的计算，增加超临界二氧化碳装置可以将涡轮机的效率提高多达 50%，且不会增加任何温室气体排放或用水量。
But retrofitting all of the country’s inefficient gas turbines powering data centers with supercritical CO2 units won’t reduce emissions to zero. Natural gas production and use, even with efficient turbines, warms the planet. Data centers also represent a massive new source of pollution—right at a time when the world needs to be scaling back on its use.
但是，用超临界二氧化碳装置改造全国所有为数据中心供电的低效燃气轮机，并不能将排放量降至零。即使使用高效涡轮机，天然气的生产和使用仍会使地球变暖。数据中心也代表了一个巨大的新污染源——而这正值全球需要减少污染排放的关键时刻。
Using supercritical CO2 for power has been studied for more than 50 years in US national labs. Over the past two decades, research has moved away from theory toward trying out practical applications, assisted by technological breakthroughs that help with the pressurization process. Doug Hofer, an adviser to American Supercritical who spent two decades at GE as a turbine engineer, says that one important innovation has been the development of more compact and more affordable heat exchangers—devices that help both heat and cool the CO2.
在美国国家实验室，利用超临界二氧化碳发电的研究已经进行了 50 多年。在过去二十年中，研究已从理论转向实际应用尝试，并得益于有助于加压过程的技术突破。曾担任通用电气（GE）涡轮机工程师二十年的 American Supercritical 顾问 Doug Hofer 表示，一项重要的创新是开发出了更紧凑、更经济的热交换器——这种设备有助于对二氧化碳进行加热和冷却。
American Supercritical isn’t the only company trying to bring this technology to market, says Subith Vasu, a professor of engineering at the University of Central Florida, who runs a lab at the school’s Center for Advanced Turbomachinery and Energy Research. The companies still have hurdles to overcome to achieve commercial success. “Whenever you are venturing into new technologies, you need to have all the associated components, the supply chain,” in place, he says. Technical challenges also abound, he adds, “and cost has been a huge issue.”
中佛罗里达大学工程学教授、该校先进涡轮机械与能源研究中心实验室负责人 Subith Vasu 表示，American Supercritical 并不是唯一一家试图将该技术推向市场的公司。这些公司要实现商业成功仍有障碍需要克服。他说：“每当你涉足新技术时，都需要具备所有相关的组件和供应链。”他补充道，技术挑战也比比皆是，“而且成本一直是一个巨大的问题。”
Hofer says that part of the delay has also simply been because larger companies are satisfied with the performance of traditional power plants and unwilling to invest in different technologies—and turbine makers are not interested in funding potential competitors. “It’s the innovator’s dilemma, right?” he says. “Getting this [technology] out there needs to have an outside influence.”
Hofer 表示，进展缓慢的部分原因仅仅是因为大公司对传统发电厂的性能感到满意，不愿投资于不同的技术，而涡轮机制造商也不愿资助潜在的竞争对手。“这就是创新者的窘境，对吧？”他说，“要让这项技术推广开来，需要外部力量的影响。”
The $7 trillion set to be invested in data centers globally by 2030 has helped open up a whole new potential market, especially for an industry racing to get as much power on the grid as it possibly can to come out ahead in the AI race. “There’s this incredible willingness to pay [for power], but they’re bottlenecked,” says Shuham. “The goal is to come in here, retrofit their existing systems, and give them the ability to build additional data centers—or get rid of some of the gas turbines.”
到 2030 年，全球预计将有 7 万亿美元投入到数据中心，这有助于打开一个全新的潜在市场，特别是对于那些竞相在电网上获取尽可能多电力以在人工智能竞赛中领先的行业而言。Shuham 说：“他们有极强的支付意愿（购买电力），但受到了瓶颈限制。我们的目标是介入其中，改造他们现有的系统，使他们有能力建设更多的数据中心——或者淘汰掉一些燃气轮机。”
Earlier this year, China announced that operations started at the world’s first geothermal plant using supercri…
今年早些时候，中国宣布全球首个使用超临界…（注：原文此处截断）