Nationalise infrastructure?

Was presenting at an interesting Oxera conference today. Amazing suggestion - not quite a proposal - from one famous speaker... when the government stands behind the main networks, as it always will.... electricity, gas, water etc. why does the consumer pay market interest rates (as the government ultimately bears the risks)? In other words, why not give these operations quasi-public sector status and let them borrow at the Treasury rate, making it cheaper for the consumer?

A most unexpected place to find the incubation of the coming era of 'new' socialism...