Discontinued operations - Mexico project development (Details) - USD ($)	Mar. 31, 2024	Dec. 31, 2023
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total assets of discontinued operations	$ 21,669,155	$ 21,340,805
Discontinued Operations. | Mexico Project Development
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash	396,525	91,283
Prepaid expenses and other current assets	145,732	120,234
Land	21,126,898	21,126,898
Other assets		2,390
Total assets of discontinued operations	21,669,155	21,340,805
Total liabilities of discontinued operations	$ 453,081	$ 364,665