Annual report pursuant to Section 13 and 15(d)

Document and Entity Information Document and Entity Information

v3.3.1.900
Document and Entity Information Document and Entity Information - USD ($)
12 Months Ended
Dec. 31, 2015
Mar. 29, 2016
Jun. 30, 2015
Entity Information [Line Items]      
Entity Registrant Name Tecogen Inc.    
Entity Central Index Key 0001537435    
Current Fiscal Year End Date --12-31    
Entity Filer Category Smaller Reporting Company    
Document Type 10-K    
Document Period End Date Dec. 31, 2015    
Document Fiscal Year Focus 2015    
Document Fiscal Period Focus FY    
Amendment Flag false    
Entity Common Stock, Shares Outstanding   18,478,990  
Entity Well-known Seasoned Issuer No    
Entity Voluntary Filers No    
Entity Current Reporting Status Yes    
Entity Public Float     $ 24,972,026