Annual report pursuant to Section 13 and 15(d)

Summary of significant accounting policies - Revenue (Details)

v3.24.1
Summary of significant accounting policies - Revenue (Details) - USD ($)
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Disaggregation of Revenue [Line Items]    
Revenue $ 25,139,419 $ 25,002,614
Payment Term on Energy Production Contract Invoices 30 days  
Revenue billed that was recognized in previous periods $ 16,428  
Deferred revenue recognized 837,571  
Remaining performance obligations $ 2,016,817  
Performance obligation recognized over next 24 months (percent) 95.00%  
Performance obligation recognized over next 12 months (percent) 13.00%  
Performance obligation recognized in subsequent 12 months (percent) 82.00%  
Products    
Disaggregation of Revenue [Line Items]    
Revenue $ 8,859,946 11,156,099
Products Segment    
Disaggregation of Revenue [Line Items]    
Revenue 8,859,946 11,156,099
Products Segment | Cogeneration    
Disaggregation of Revenue [Line Items]    
Revenue 2,761,667 5,279,569
Products Segment | Chiller    
Disaggregation of Revenue [Line Items]    
Revenue 5,303,978 5,034,633
Products Segment | Engineered Accessories    
Disaggregation of Revenue [Line Items]    
Revenue 794,301 841,897
Services Segment    
Disaggregation of Revenue [Line Items]    
Revenue 25,139,419 25,002,614
Services Segment | Installation Services [Member]    
Disaggregation of Revenue [Line Items]    
Revenue 14,523,054 12,060,661
Services Segment | Energy Production    
Disaggregation of Revenue [Line Items]    
Revenue 1,756,419 1,785,854
Energy Production    
Disaggregation of Revenue [Line Items]    
Revenue 1,756,419 1,785,854
General and Administrative Expense    
Disaggregation of Revenue [Line Items]    
Shipping and handling expenses 427,880 563,482
Operating Segments    
Disaggregation of Revenue [Line Items]    
Revenue 25,139,419 25,002,614
Operating Segments | Products Segment    
Disaggregation of Revenue [Line Items]    
Revenue 8,859,946 11,156,099
Operating Segments | Energy Production    
Disaggregation of Revenue [Line Items]    
Revenue $ 1,756,419 $ 1,785,854