In the 1970s, American researchers estimated that getting fusion power on the grid would demand investment of $2-3 billion annually in research and development until anywhere from 1990 to 2005 (depending on the amount of effort applied). They also estimated a minimum level of investment, below which funding would never be sufficient to build a fusion power plant.
20世纪70年代，美国研究人员曾预计实现核聚变发电并网需要在1990到2005年间每年20-30亿美元的研发投入（具体投资规模取决于工作量情况）。他们还估算了最低投资水平（低于该水平永远不可能建立聚变电厂）。30年来核聚变研究预算一直处于该水平之下。