Quarterly report pursuant to Section 13 or 15(d)

Document and Entity Information Document and Entity Information

v3.19.3
Document and Entity Information Document and Entity Information - shares
9 Months Ended
Sep. 30, 2019
Oct. 31, 2019
Document and Entity Information [Abstract]    
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-Q  
Document Period End Date Sep. 30, 2019  
Document Fiscal Year Focus 2019  
Document Fiscal Period Focus Q3  
Amendment Flag false  
Entity Common Stock, Shares Outstanding   24,843,261
Entity Shell Company false  
Entity Emerging Growth Company false  
Entity Small Business true  
Entity Current Reporting Status Yes