Open Questions

The energy atlas's own register of unresolved or contested points: disputed founding dates, unsettled attributions, and figures still argued over by historians of the field. It flags where the record itself is not settled, rather than presenting one claim as fact, and excludes the ordinary status caveats already attached to individual facts elsewhere on the site.

Open Questions

How much long-duration grid-scale energy storage will be needed, and at what cost, as the share of renewable generation grows?

What exact date in 1712 did Thomas Newcomen's first practical steam engine begin operating?

What exact date in July 1887 did James Blyth's wind turbine at Marykirk first generate electricity?

What was the exact date in 1712 that Newcomen's engine at Conygree began operating?

What was the exact date in July 1887 that Blyth first ran his wind turbine at Marykirk?

What year did the first commercial landfill gas energy recovery facility begin operating?

When did biomass energy first become a commercial power source, as distinct from its individual fuels?

When did commercial charcoal production and trade begin?

When did commercial trade in dried dung as a fuel begin?

When did commercial trade in firewood as a fuel begin?

When was Henry J. Rogers born and when did he die?

When was the Aswan High Dam completed?

When was the solid oxide electrolyzer cell first developed?

When will deep geological disposal of high-level nuclear waste become operational at scale?

When, and by whom, was the term "just transition" first used?

When, if ever, will methane hydrates become an economically viable commercial energy source?

When, if ever, will nuclear fusion reach its first commercial year of electricity generation?

When, if ever, will nuclear fusion reach sustained, commercial electricity generation?

When, if ever, will the first fusion power plant begin generating electricity commercially?

Will methane hydrates ever become a commercially extracted energy source?