Salvesen, a leading figure in the UK’s seafood industry who has directorships in a number of businesses, now owns 23.01 per cent of the cleantech firm, up from 22.39 per cent.
New chief operating officer, William Ingram Hill, 35, also bought recently 250,000 shares in the company for 11.5p each.
Helius is developing biomass-fired renewable electricity generation plants at sizes ranging from around seven megawatts to 100MW.
The firm is involved in several projects and its long-term aim is to be an owner/operator of 500MW worth of power plant assets.
The group is focused on a 100MW Avonmouth biomass plant, located on the Bristol Channel; a 7.2MW project in Scotland with the Combination of Rothes Distillers (CoRDe); and another 100MW biomass plant proposed for Southampton.
Helius also developed the 65MW net capacity Stallingborough biomass plant, located on the south side of the Humber estuary in Lincolnshire.
Helius Alpha, a subsidiary that owned the rights to develop and operate the plant, was then sold in its entirety to RWE Innogy.
In early October, Helius raised £6.6 million in a placing priced at 16p pence per share.