Solar panels with storage keep a lunar polar site powered through a whole year

Near the Moon's poles, a few ridges and crater rims are in sunlight most of the time, because the Sun circles low along the horizon there. Tall solar masts on such a ridge, with batteries or fuel cells for the short dark spells, can keep a site powered without a reactor. The US space agency has funded tall-mast solar designs for this purpose, and it is the route most likely to arrive first if the lunar reactor keeps slipping.

The test: what counts as it having happened

A solar power system with energy storage, at a lunar site within ten degrees of latitude of either pole, makes at least forty kilowatts of net electrical output available to external loads for at least ninety percent of a twelve-month period, with no nuclear source contributing, confirmed by the responsible agency's or company's mission record.

Settled by: The responsible agency's or company's mission record

The odds, by how long I live

baselineto 2071 ± 8	moderateto 2080	strongto 2095	radicalto 2136	openno deadline
65%	76%	86%	92%	94%

Each column is a different guess at how long I live, from current trends (baseline) to open-ended. The number is the chance this happens before that deadline, assuming everything it depends on happens first. As of 2026-10-02.

Why these numbers: First estimate of 2026-09-25 raised at John's ruling on 2026-10-02: every south-pole base plan starts on solar, so sitting fifteen points under the reactor was too cautious; it stays below the reactor because the reactor is the planned answer. The reasoning of the first estimate follows. The panels, masts and storage are ordinary engineering and every south-pole base plan starts on solar, but forty kilowatts (this route's own bar, the same as the reactor's; the step up to a hundred kilowatts is priced separately in the step above) held through a full year of dark spells and dust has not been attempted, and a programme that gets its reactor may never build a solar plant this size. Set below the reactor because the reactor is the planned answer.

What this one is worth

If this happened tomorrow and nothing else changed, the chance that I live and work off Earth by 2071 goes from 0.5% to 0.4% (too small to tell apart from chance). If it turned out no, the same number goes to 0.5% (too small to tell apart from chance).

Longevity scenario	baseline2071 ± 8	moderate2080	strong2095	radical2136	openno deadline
The headline as it stands	0.5%	1.2%	3.8%	11%	15%
If this settled yes now	0.4%	1.2%	3.9%	11%	15%
If this settled no now	0.5%	1.3%	3.7%	11%	15%

This is what the site says in advance, before the thing happens. When it does, the ledger entry that records it quotes this figure beside what actually followed, so a reader can see whether the prediction held. Worked out at the run 2026-10-11-scan by holding this step at each outcome in turn and playing the whole tree out again, 20,000 times per scenario. That is a throw of the dice, so a move smaller than about 0.10 points is inside the noise rather than a finding.

What the ledger says about this step

• Solar panels with storage keeping a lunar polar site powered for a year was raised at John's ruling: every south-pole base plan starts on solar 2026-10-02 Changed my mind

The last check

Once a week the tree is read against the news, node by node, against the test above. Open a line to see what that week held. Every check ever made on this node is on the Radar page.

• 2026-10-04 Nothing new

  No polar solar-plus-storage system has operated on the Moon; Astrobotic's LunaGrid and VOLT remain in ground testing with an operational target of 2028.

Revisions

Date	Field	From	To	Why
2026-10-02	probability	0.55 / 0.68 / 0.82 / 0.90 / 0.93	0.65 / 0.76 / 0.86 / 0.92 / 0.94	Ruling on the first estimates of the function-over-route pass (pull request 29). Claude, reviewing the first estimate, proposed 0.65 by 2071 on the ground that every south-pole base plan starts on solar while the reactor stands at 0.70; John accepted on 2026-10-02. The figures for the four longer windows are Claude's, scaled to keep the same shape and to stay below the reactor in every window.

Notes

Added 2026-09-25 as a route under E-power-through-the-lunar-night-at-a-surface-site (candidate 1 of docs/proposal-function-over-route-2026-09-25.md, approved by John 2026-09-25). The forty-kilowatt threshold and the ninety-percent-of-a-year test match the reactor route, so the routes are like for like. Solar with storage was the alternative logged against the reactor link at step 27, item 61 (2026-09-19).

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Think this is wrong, missing something it depends on, or badly estimated? Open an issue about it, or read how feedback gets folded into the tree. The record itself is data/E-energy.toml in the public repository.