Authoritarian regimes and financial giants with stakes in the fossil fuel industry are among investors who would benefit from plans to use hydrogen heating.
Oil giant Shell is trying to get a staff member elected to the board of Scotland's renewable energy body, leading to concerns.
As many as 43 members of the House of Lords have investments totalling millions of pounds and senior roles in oil and gas companies.
The Science Based Targets initiative (SBTi), which aims to “independently assess" corporate climate pledges, is developing its guidance alongside fossil fuel polluters.
Registers of Scotland data shows 3,237 Scottish properties were owned by companies based outside of the UK in 2019.