Annual report pursuant to Section 13 and 15(d)

Summary of significant accounting policies - Revenue by Product Line and Services (Details)

v2.4.1.9
Summary of significant accounting policies - Revenue by Product Line and Services (Details) (USD $)
 12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Revenue by Producks and Services [Line Items]    
Products $ 8,625,034us-gaap_SalesRevenueGoodsNet $ 6,346,050us-gaap_SalesRevenueGoodsNet
Services 10,717,630us-gaap_SalesRevenueServicesNet 9,503,819us-gaap_SalesRevenueServicesNet
Total revenues 19,342,664us-gaap_SalesRevenueNet 15,849,869us-gaap_SalesRevenueNet
Cogeneration    
Revenue by Producks and Services [Line Items]    
Products 5,364,810us-gaap_SalesRevenueGoodsNet
/ us-gaap_ProductOrServiceAxis
= tcgn_CogenerationMember 		5,199,649us-gaap_SalesRevenueGoodsNet
/ us-gaap_ProductOrServiceAxis
= tcgn_CogenerationMember
Chiller    
Revenue by Producks and Services [Line Items]    
Products 3,260,224us-gaap_SalesRevenueGoodsNet
/ us-gaap_ProductOrServiceAxis
= tcgn_ChillerMember 		1,146,401us-gaap_SalesRevenueGoodsNet
/ us-gaap_ProductOrServiceAxis
= tcgn_ChillerMember
Service contracts    
Revenue by Producks and Services [Line Items]    
Services 7,438,125us-gaap_SalesRevenueServicesNet
/ us-gaap_ProductOrServiceAxis
= tcgn_ServiceContractsMember 		7,071,388us-gaap_SalesRevenueServicesNet
/ us-gaap_ProductOrServiceAxis
= tcgn_ServiceContractsMember
installations    
Revenue by Producks and Services [Line Items]    
Services $ 3,279,505us-gaap_SalesRevenueServicesNet
/ us-gaap_ProductOrServiceAxis
= tcgn_InstallationsMember 		$ 2,432,431us-gaap_SalesRevenueServicesNet
/ us-gaap_ProductOrServiceAxis
= tcgn_InstallationsMember