The whole Internet hacker bringing down the grid is being wholly overplayed. It is just being touted as an excuse for the potential failings of an old and unfunded and poorly maintained network. Its easy to blame the computer hacker from Ulan Bator sitting in his Yurt for when the US grid falls over. The same situation is being repeated here in the UK.
http://www.guardian.co.uk/business/2009/nov/01/winter-crisis-gas-suppliesThere is a direct relationship between profit, operating cost and safety.
As for the nuclear power station issue, it is unlikely that that a nuclear power station will go bang if an emergency shutdown is called for. But it is not highly unlikely or impossible, the events at 3 mile island and Chernobyl have shown that it is possible. Indeed Chernobyl had shown that testing the emergency shutdown of the reactor to implement a safety procedure eventually led to the reactor going bang.
The 3 mile island event was just a incredulous as Chernobyl, as the operators didn't understand the status of one panel indicator in the control room. Even worse, safety critical engineering systems just simply failed and were known to fail such as the pilot-operated relief valve PORV. Even the primary feedwater pump system failed.
Once the primary feedwater pump system failed, three auxiliary pumps activated automatically. However, because the valves had been closed for routine maintenance, the system was unable to pump any water. The closure of these valves was a violation of a key NRC rule, according to which the reactor must be shut down if all auxiliary feed pumps are closed for maintenance. This failure was later singled out by NRC officials as a key one, without which the course of events would have been very different.[9] The pumps were activated manually eight minutes later, and manually deactivated between 1 and 2 hours later,[9] as per procedure, due to excessive vibration in the pumps.[
A lamp in the control room, designed to light up when electric power was applied to the solenoid that operated the pilot valve of the PORV, went out, as intended, when the power was removed. This was incorrectly interpreted by the operators as meaning that the main relief valve was closed, when in reality it only indicated that power had been removed from the solenoid, not the actual position of the pilot valve or the main relief valve. Because this indicator was not designed to unambiguously indicate the actual position of the main relief valve, the operators did not correctly diagnose the problem for several hours.
Even more telling;
The Kemeny Commission noted that Babcock and Wilcox's PORV valve had previously failed on 11 occasions, 9 of them in the open position, allowing coolant to escape. More disturbing, however, was the fact that virtually the entire sequence of events at TMI had been duplicated 18 months earlier at another Babcock and Wilcox reactor, owned by Davis-Besse. The only difference was that the operators at Davis-Besse identified the valve failure after 20 minutes, where at TMI it took 2 hours and 20 minutes; and the Davis-Besse facility was operating at 9% power, against TMI's 97%. Although Babcock engineers recognised the problem, the company failed to clearly notify its customers of the valve issue
Yet these known issues were not acted on.
All I was suggesting was that a no load situation may result in a catastrophic disaster for a nuclear power station. The emergency shutdown procedure may start a chain of incorrect decision making and the engineering failures of critical safety systems, which may have not even been foreseen. Even as something as simple as the emergency diesel generator set not starting up simply because someone had pilfered the diesel.
An example of something similar was the test firing of a Royal Navy anti shipping guided missile (Harpoon) which failed. A senior ranking RN officer had aquired the then new missile 128Mbyte SDRAM DIMMs for his own personal computer.
