Are blackouts contagious

Six blackouts within six weeks affected about 112 million people in the US, UK, Denmark, Sweden and Italy. People started to ask: is it a coincidence; is liberalisation to blame; who is next? There is one difference between the blackouts in the US and continental Europe and those in the UK: in the former, the blackouts started at the interconnections between neighbouring networks and spread across boundaries. In the UK, the two blackouts were very similar to each other but were both within the control area of a single control centre managed by National Grid. In the case of US and Italy, the events spread due to insufficient co-ordination between system operators. Is liberalisation (called deregulation in the US) to blame? The author discusses this issue. It is not liberalisation to blame as such, rather that the system operators did not seem to have adjusted to the new situation. Although the current investment in US grid lags behind historical numbers, it is not the level of investment that determines whether a grid is vulnerable to blackouts, but rather, operational rules.