If you survived the bug of the "2000 year problem", Y2K, then you may remember this hype almost without any consequences. With the transition of the calendar from 1999 to 2000, many predicted an autopsy of catastrophic errors in the software of machines that controlled our banks and infrastructures. A potential catastrophe did not meet expectations, but at the beginning of the new millennium another serious infrastructure disaster occurred, leading to massive blackouts (blackouts) in North America. In terms of the scale of the tragedy, it might seem that the belated consequences of Y2K worked, but the actual cause of the outages was simply the organizational problems of the network itself.
Built-in protective equipment
Although the scale offsets of those that occurred in the early 2000s are quite rare, small local outages almost always occur sooner or later. Although power plants are motivated to maximize protection from these incidents (there is no energy – meters do not spin), there is no guaranteed way to protect against lightning striking the power line or expensive equipment, or from indecipherable electricians, overloading panels and damaging transformers, or from birds, The nests of the substations.
In theory, if there is any problem (failure of the electrical system), there are a great many protective devices designed to minimize downtime to a minimum. Most of the problems are short-term failures, self-eliminating rather quickly. A lightning stroke may strike the line, or a branch may fall on it. Instead of disabling the safety interrupter, which will then need to be turned on manually, small devices for automatic reclosing (reclosing) can re-apply voltage to the network sections that experienced a temporary failure (unstable damage). In the case of permanent damage, a larger interrupter will operate, but it will have to be turned on manually, after the damage has been eliminated by the electricians. In the electrical network, one-time fuses are often found, which, in contrast to automatic reclosers and circuit breakers, must then be replaced.
Toronto during a massive power outage
But all this protective equipment has its drawbacks, and under certain conditions it can start behaving badly, which can lead to unusual consequences. This was the case during the northeastern trip of 2003, when the Ohio transmission line touched the tree. Usually such a case would be quickly resolved with the help of protective equipment and network operators. But it was a summer day, and the contact was due to the fact that the line sagged more than usual, transmitting current close to the maximum possible. More current means more thermal expansion of the wires, and more chances to come in contact with what is not needed.
Since it was a summer day, after disabling the first transmission line, the entire normal load plus the entire peak load should have been distributed over other circuits to To avoid lack of energy. And usually it would be easy to do, but the other circuits were also under peak load, and after they were suddenly transferred to additional energy, they turned off, causing more lines to become overloaded, and more circuits went out. As a result, more than 50 million people in the US and Canada were left without electricity. At that time, it was the second most common power outage [крупнейшее за всю историю отключение случилось в Индии в 2012 году и затронуло 620 млн чел. – прим. перев.]and led to such simple circumstances as a hot day and a small bug in the computer that allowed cascading outages to quickly get out of hand.
Times Square during shutdown in 2003
It should be noted that energy companies are commercial organizations, therefore building a power grid that is more durable than necessary does not have a commercial meaning. Of course, it always makes sense to have additional safety capacity, and the company from Ohio at some point could really act disdainfully, but at least they were not completely negligent. In addition, the rear mind is always easy to find guilty.
Shutdowns as a business model
On the other hand, there were such outages that were specially organized by companies seeking to profit from it . The California energy crisis of 2000-2001 is an almost elementary example of a conflict of interest, when an energy seller like Enron, which controls the supply of energy to the state, also trades energy futures. This practice has already been banned, but it required that this company, known today for corruption, dubious business practices and bankruptcy, catalyze changes in laws that allowed such a lack of regulation in the energy market. California during this crisis was constantly subjected to cascading inclusions, despite the fact that the power transmission system was reliable enough to withstand all the requests, and the generating capacity was sufficient to meet the needs of the entire staff without any disconnections.
New York during the shutdown of 1977
We start the power station by "lighting up"
Despite Enron's increased regulatory powers in North America, which is able to cope with such problems, energy companies are obliged to restore power after shutdown. Although damage to the network must be repaired, it must not be fed from the nuclear power plant or from a gas turbine – it's not as easy as clicking the switch. If the power plant ceases to generate power, it needs either external power or a so-called power supply to start it. System of "black start" (generators), launching larger diesel generators, giving the necessary energy. It is necessary to run steam boilers, move control rods, supply fuel – and for all this, energy is required. Hydropower stations are usually used for the "black start" of the company, but other technologies are used in places where it is impossible to block the river.
Small energy outages can happen anywhere, and large ones occur relatively rarely, despite the aging infrastructure and negligent companies. Of course, in the scale of an entire network, energy transfer can go on a very complex scheme. In the following articles of the series, we will consider smart networks: modern modernization of the power grid and how modern technologies help to improve it.