Accounting policies - Disaggregated revenue (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Total Revenue	$ 49,854,075	$ 25,051,705	$ 126,960,328	$ 65,676,737
Contracts in progress
Increase in net income	$ 1,350,108		$ 2,680,936
Increase in diluted earning	$ 0.08		$ 0.17
Minimum [Member]
Contracts in progress
Number of days after consumption billings are collected			30 days
Maximum [Member]
Contracts in progress
Number of days after consumption billings are collected			45 days
Retail revenue [Member]
Total Revenue	$ 7,216,574	6,274,650	$ 22,560,998	19,114,653
Bulk revenue [Member]
Total Revenue	8,488,615	8,667,931	25,975,483	24,442,324
Services revenue [Member]
Total Revenue	29,427,664	8,731,124	66,243,328	18,530,427
Contracts in progress
Increase in net income	1,787,275		3,549,028
Manufacturing revenue [Member]
Total Revenue	4,721,222	1,378,000	12,180,519	3,589,333
Construction Sevices [Member]
Total Revenue	24,204,446	4,781,613	52,563,822	5,347,023
Operations and Maintenance [Member]
Total Revenue	5,021,081	3,394,142	12,750,902	10,740,623
Design and Consulting Services [Member]
Total Revenue	$ 202,137	$ 555,369	$ 928,604	$ 2,442,781