v3.25.1
Summary of significant accounting policies (Details Narrative)
12 Months Ended
Dec. 31, 2024
USD ($)
shares
Dec. 31, 2024
CNY (¥)
Dec. 31, 2023
USD ($)
shares
Dec. 31, 2023
CNY (¥)
Dec. 31, 2022
USD ($)
Dec. 31, 2022
CNY (¥)
Mar. 03, 2021
shares
Oct. 08, 2019
shares
Research and development costs $ 0   $ 0   $ 0      
Advertising and promotional expenses $ 41,000   $ 29,000   $ 9,000      
Common stock, issued | shares 7,899,832   7,899,832       2,061,900 1,030,950
Remaining performance obligation $ 4,022,000   $ 3,839,000          
Revenue from Contract with Customer, Increase (Decrease) $ 183,000              
Revenue                
Concentration percentage 47.00% 47.00% 41.00% 41.00% 33.00% 33.00%    
ZHEJIANG TIANLAN                
Research and development costs | ¥   ¥ 27,371,000   ¥ 20,452,000   ¥ 29,115,000    
Impairment of long-lived assets $ 0     ¥ 0 $ 0      
Common stock, issued | shares 82,572,000   82,572,000          
ZHEJIANG TIANLAN | Revenue                
Concentration percentage 42.00% 42.00% 38.00% 38.00% 35.00% 35.00%    
ZHEJIANG TIANLAN | Revenue | Customer One                
Concentration percentage 16.00% 16.00% 22.00% 22.00% 14.00% 14.00%