2005 年，美国国会通过了《2005年能源政策法案》，该法案授权在2021年之前建造和运行一个高温气冷堆(HTGR)。在美国国内专家对未来核技术发展方向进行了多年的研究后，该法案才得以通过。作为该法案的结果，美国国会设立了名为'下一代核电站'的项目，这是一种为制氢提供工艺用热的HTGR。尽管HTGR被寄予了很高的期望，但其现状仅限于完成关于先进燃料、石墨和其他材料的研究计划，并不是如国会在2005年提出的建造一个示范电站。HTGR 发展目标降低背后有许多原因，包括：用于研究的政府资金不足，对反应堆不切实际的高温要求，对'氢'经 济需求的延迟，来自轻水冷却的小型模块反应堆的竞争，业主公司对新技术的兴趣较低，美国天然气价格过低，以及美国对非水冷反应堆许可证申请的具有挑战性的流程等。

In 2005, the US passed the Energy Policy Act of 2005 mandating the construction and operation of a high-temperature gas reactor (HTGR) by 2021. This law was passed after a multiyear study by national experts on what future nuclear technologies should be developed. As a result of the Act, the US Congress chose to develop the so-called Next-Generation Nuclear Plant, which was to be an HTGR designed to produce process heat for hydrogen production. Despite high hopes and expectations, the current status is that high temperature reactors have been relegated to completing research programs on advanced fuels, graphite and materials with no plans to build a demonstration plant as required by the US Congress in 2005. There are many reasons behind this diminution of HTGR development, including but not limited to insufficient government funding requirements for research, unrealistically high temperature requirements for the reactor, the delay in the need for a 'hydrogen' economy, competition from light water small modular light water reactors, little utility interest in new technologies, very low natural gas prices in the US, and a challenging licensing process in the US for non-water reactors.