My Lords, I agree with my noble friend that the degree of disruption that was caused was considerable. It is intolerable to have such disruption to surface rail, Underground, street lighting and traffic systems. That is why we immediately called for reports.

The reports suggest that the problems were not to do with investment levels but with operator failure in the two situations. We think that, because of the seriousness of the situation, things should not be left at that, which is why my colleague, Stephen Timms, has set in motion two further pieces of work. Ofgem and DTI will jointly commission consultants to do some initial fact-finding. Those findings will be made public. Secondly, the DTI engineering inspectorate will conduct a full, independent investigation to establish whether the companies involved in the interruptions complied with the relevant technical requirements.