Related party transactions (Details Narrative) - ZHEJIANG TIANLAN	12 Months Ended
Dec. 31, 2024 USD ($)	Dec. 31, 2023 CNY (¥)	Dec. 31, 2024 CNY (¥)
Investment		¥ 4,469,000	¥ 4,708,000
Engineering Service
Investment	$ 0	0
Remuneration	$ 2,037,000	¥ 1,878,000

Sum of the carrying amounts as of the balance sheet date of all investments.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 944
-SubTopic 80
-Name Accounting Standards Codification
-Section 55
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Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 944
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant