The Argonne concept for the boiling water reactor was said to be promising according to recent experiments, and would be proven by an eventual 20,000 kilowatt thermal experimental BWR which would drive a 5000-kilowatt turbine generator. The sodium graphite concept was under « extensive investigations » by North American, and would result in a 20,000-kw reactor with no turbogenerator. A fast breeder to follow EBR-I was announced under the plan, scaled up from the EBR-I rating of 1400 kilowatts to a core rating of 62,500 kilowatts. The (aqueous) homogeneous design would be built for this five-year program as an upscale of the HRE-I at Oak Ridge; the first reactor produced only 1000 kilowatts, but HRE-2 would produce 5000; this plant would include chemical reprocessing facilities and a turbogenerator.

https://www.ans.org/news/article-1493/eisenhowers-atomic-power-for-peace-the-civilian-application-program-ii/

HRE-2 reactor pressure vessel being installed. « Atoms for Peace USA 1958 » – see sources.