Discontinued operations - Mexico project development (Details) - Discontinued Operations - Mexico Project Development - USD ($)	Sep. 30, 2025	Dec. 31, 2024
Discontinued operations - Mexico project development
Cash	$ 26,115	$ 127,859
Prepaid expenses and other current assets	110,813	144,626
Total assets of discontinued operations	136,928	272,485
Total liabilities of discontinued operations	$ 271,143	$ 509,745

Amount classified as assets attributable to disposal group held for sale or disposed of.

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