The deal follows an earlier £4 million investment from the same firm in December 2007. Impax, which invested from its Environmental Markets investment trust and its open-ended Irish fund of the same name, now holds a stake of 16.3 per cent in the company.

The funding will assist with a planned roll-out of waste management facilities across the UK. New Earth, which already has operational facilities in Dorset and Kent, has recently been granted planning permission to build a further plant in Bristol, and is due to begin construction of another in Leicestershire.

Peter Gillat, New Earth’s managing director, says the new funding will help the company ‘take advantage of new opportunities in the waste to energy sector, where the synergies with our established waste treatment business are increasingly compelling’.

In 2007 the company secured £50 million in debt finance from German bank Norddeutsche Landesbank, and since July 2008 it has raised £7 million from UK retail investors through its offshore investment vehicle, New Earth Recycling Facilities Investment Sub-Fund.