A NERA team led by Director Sean Gammons and Senior Consultant Richard Druce has collaborated with an Imperial College London team led by Professor Goran Strbac on a report for RWE npower in the context of “Project TransmiT,” Ofgem’s fundamental review of electricity transmission charging and access arrangements in Great Britain (GB). The team was commissioned to compare the current system of locational transmission network use of system (TNUoS) charges for GB power generators with a system of uniform generator charges, using simulation models of the power market and the transmission system. Their analysis demonstrates that the removal of locational cost signals from generation TNUoS charges significantly affects the locational decisions of the circa 60GW of new wind and gas-fired generation that is needed in GB over the next two decades. As a result, they find that uniform TNUoS would increase costs to consumers in the period to 2030 by around £20 billion in present value terms. At the same time, they find no difference between the two charging models in terms of meeting the UK government’s targets for reducing CO2 emissions and increasing the use of renewables in power generation.  They therefore conclude that the current system of locational generation TNUoS is economically efficient relative to a uniform charge, and sustainable in terms of meeting the UK government’s green targets.