Energy Aperture

Space-based solar power, claim by claim

Governments and companies in the UK, China, Japan and the US are studying whether solar power collected in orbit, where sunlight is almost continuous, could be beamed down as microwaves to supply the grid. The evidence is spread across agency reports, company statements and journal papers, with few places that bring them together.

This site gathers it into one register. Each claim is numbered and dated, graded by the kind of evidence behind it, read against its source and checked by a second reader.

Browse the value chain How the grading works

The 3D explorer: the Earth, the ring of geostationary orbit, and a solar power satellite beaming power to a receiving site.
Open the explorer: a true-scale 3D model of each design, from sunlight on the collectors to power at the receiving site. Every figure in it is cited to a record or marked illustrative. About 13.9 MB; works on a phone. Imagery: NASA Earth Observatory (Blue Marble Next Generation); NASA Goddard Space Flight Center (Black Marble 2016).

Where to start

About the register

Five primary documents name no beam-safety exposure standard

A full-text search of five primary documents on beam safety found no named exposure standard, a limit on how much microwave power people may receive. The documents may rely on assessments published elsewhere (CLM-0006).

UK Phase 1 feasibility Frazer-Nash 2021, full Frazer-Nash 2021, summary CASSIOPeiA paper NASA OTPS 2024 ICNIRP 00000 IEEE C95 00000 exposure limit 00000 exposure guideline 00000 safety standard 00000 regulatory limit 00000 non-ionising 00000 exclusion zone 00000 keep-out 00000 restricted area 00000 controlled area 00000 0 occurrences, of eleven terms 288 pages searched, every page of five 5 primary documents, searched in full, as at 2026-09-12 Absence of a term is not absence of a safety case: these five may rely on an assessment published elsewhere. What it shows is that these five do not name the standard their safety discussion uses. The calculation behind it states it should not be relied on until the text-layer completeness of all five documents is confirmed.
CLM-0006, searched and shown in full at CALC-040. Full text extracted and searched case-insensitively across every page of all five documents. Each zero is a search that ran and found nothing.