Discontinued operations - Mexico project development (Details) - USD ($)	Jun. 30, 2024	Dec. 31, 2023
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total assets of discontinued operations	$ 1,503,473	$ 21,340,805
Discontinued Operations. | Mexico Project Development
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash	1,355,104	91,283
Prepaid expenses and other current assets	148,369	120,234
Land		21,126,898
Other assets		2,390
Total assets of discontinued operations	1,503,473	21,340,805
Total liabilities of discontinued operations	$ 393,237	$ 364,665