International Public Partnerships (INPP) said it has taken a "key step" with the Lincs offshore transmission project following an announcement by Ofgem.INPP is part of a consortium that was selected by the regulator to own and operate the high voltage transmission link to the 250 megawatt offshore wind farm.The group said that the consortium has moved closed to reaching financial close on its expected investment, which is now expected to be made in November.The consortium anticipates making an investment of around £170m, which will not exposure INPP to electricity production or price risk and will be paid via a pre-agreed, availability-based revenue stream over 20 years which is fully linked to UK inflation based on the retail price index.It will be the FTSE 250-listed group's fifth offshore transmission owners project.Shares were lifted 1.38% to 132.50p by 11:38 on Thursday.