Analysis: Understanding how the power grids in the United States are connected, and how they work is key to understanding how their vulnerabilities can be so devastating. We will take a look at the power grid systems here in the US, as well as learn a bit about what black start facilities, why they are important, and what role they play in a grid down situation.
Areas of Interest: United States
Impact: The first thing we should touch on is how power grids are divided up to run the country. We need to know exactly what is tied to what to fully understand the ramifications of a successful attack on the power grid from one of our enemies. There are actually (4) interconnections that the US depends on, and within those (4) are (8) regional entities. All this is overseen by NERC, North American Electric Reliability Corporation. There are MANY sources that create the power we use, such as wind, solar, and traditional power plants (coal, nuclear, gas, hydro, etc.) The electric power transmission grid of the contiguous United States consists of 190,000 kilometers (120,000 mi) of lines operated by 500 companies. NERC also operates the Electricity Information Sharing and Analysis Center (E-ISAC). The E-ISAC offers security services to bulk power system owners and operators across North America. E-ISAC member services includes specific cyber and physical security threat intelligence, tailored cyber security knowledge and physical security collaboration. The E-ISAC, which NERC established at the request of the U.S. Department of Energy, does real time monitoring of the system. The E-ISAC uses the Cyber Security Risk Information Sharing Program (CRISP), and works with critical asset owners and operators to analyze real-time cyber and physical security data for patterns of incidents with the potential to impact the bulk power system.
Understanding how it all works:
Early electricity systems, such as those installed by George Westinghouse and Thomas Edison, prior to the start of the 20th Century were isolated central stations that served small pockets of customers independently of each other. As these systems grew to cover larger geographic areas, it became possible to connect previously isolated systems, allowing neighboring systems to share generation and voltage stability resources. However, tying power systems together with these early interconnections also introduced the risk that a single significant disturbance could collapse all of the systems tied to the interconnection. Generally, it was decided that the benefits outweighed the risks, and by 1915 interconnections began to flourish and grow in size. By the end of the 1960s, there were virtually no isolated power systems remaining in the lower 48 states and southern Canada; practically all power companies were attached to large interconnections.
Unlike water or gas, electricity cannot be stored in large quantities. It must be generated at the instant it is used, which requires supply be kept in constant balance with demand. Furthermore, electricity flows simultaneously over all transmission lines in the interconnected grid system in inverse proportion to their electrical resistance, so it generally cannot be routed over specific lines. This means generation and transmission operations in North America must be monitored and controlled in real time, 24-hours-a-day, to ensure a reliable and continuous supply of electricity to homes and businesses. System disturbances that result in the unplanned and/or uncontrolled interruption of customer demand, regardless of cause, fall under the heading of operating reliability. When these interruptions are contained within a localized area, they are considered unplanned interruptions or disturbances. When they spread over a wide area of the grid, they are referred to as cascading outages — the uncontrolled successive loss of system elements triggered by an incident at any location. Cascading results in widespread service interruption. So, as you can see, being interconnected makes sense, and has allowed us to become the superpower that we are, but it also has its caveats.
Electrical power starts at the power plant. In almost all cases, the power plant consists of a spinning electrical generator. Something has to spin that generator — it might be a water wheel in a hydroelectric dam, a large diesel engine or a gas turbine. But in most cases, the thing spinning the generator is a steam turbine. The steam might be created by burning coal, oil or natural gas. Or the steam may come from a nuclear reactor. The power plant produces three phase power (too in depth for this article), and it leaves the generator and enters a transmission substation at the power plant. This substation uses large transformers to convert or “step up” the generator’s voltage to extremely high voltages for long-distance transmission on the transmission grid. Typical voltages for long distance transmission are in the range of 155,000 to 765,000 volts. A typical maximum transmission distance is about 300 miles. For power to be useful in a home or business, it comes off the transmission grid and is stepped-down to the distribution grid. This may happen in several phases. The place where the conversion from “transmission” to “distribution” occurs is in a power substation (very vulnerable much of the time – soft target). The power goes from the transformer to the distribution bus. The bus distributes power to local distribution lines. The bus has its own transformers that can also step down or step up voltage according to local energy needs.
- Eastern Interconnect – The Eastern Interconnection covers most of eastern North America, extending from the foot of the Rocky Mountains to the Atlantic seaboard, excluding most of Texas. The Eastern Interconnection is tied to the Western Interconnection via high voltage DC transmission facilities and also has ties to non-NERC systems in northern Canada.
- Western Interconnect – The Western Interconnection covers most of western North America, from the Rocky Mountains to the Pacific coast. It is tied to the Eastern Interconnection at six points, and also has ties to non-NERC systems in northern Canada and Northwestern Mexico.
- Texas Interconnect – The Texas Interconnection covers most of the state of Texas. It is tied to the Eastern Interconnection at two points, and also has ties to non-NERC systems in Mexico. Parts of East Texas as well as the Panhandle belong to the Eastern Interconnect.
- Quebec Interconnect – The Quebec Interconnection covers the province of Quebec and is tied to the Eastern Interconnection at two points. About one third of Canada’s installed power (42 GW out of 130) and about one third of Canada’s production (184 TWh out of 567) are in this interconnection. Despite being a functionally separate interconnection, the Quebec Interconnection is often considered to be part of the Eastern Interconnection.
- Florida Reliability Coordinating Council (FRCC)
- Midwest Reliability Organization(MRO)
- Northeast Power Coordinating Council (NPCC)
- ReliabilityFirst (RF)
- SERC Reliability Corporation (SERC)
- Southwest Power Pool, Inc. (SPP RE)
- Texas Reliability Entity (Texas RE)
- Western Electricity Coordinating Council (WECC)
If you want to see what a very small coordinated attack on a section of a grid can do, one only has to look at the PG&E Metcalf Station attack in 2013. Multiple gunmen fired high powered rounds into 17 very large transformers. The transformers leaked 52,000 gallons of oil, overheated, and failed. There were widespread and numerous outages, and the dollar amount of the equipment loss was valued at $15 Million. This was a coordinated attack by a small group of individuals, and has been the most significant attack on our power grid. Our achilles heel in this country right now is our power grid, and if it were to go down it would affect everything that we do in this country. So, what is in place to fix this if it does happen? Our country, as well as others, are depending on what are known as black start facilities.
Black Start Facilities
Just what is meant by black start? How does it work?
Black start is a process of restoring a power station to operation without relying on external energy sources. A typical black start scenario includes black start generating units providing power to start large steam turbine units located close by. It also involves the supply of auxiliary power to nuclear power stations and off-site power to critical service loads, such as hospitals and other public health facilities, and military facilities. Transmission lines must be available to deliver cranking power to non-black-start (NBS) units or large motor loads, and transformer units, including step-up transformers of black start units and steam turbine units, and auxiliary transformers serving motor control centers at the steam plant. Following an outage of the power system, power stations usually rely on power provided from the station’s own generators. For example, small diesel generators can provide electric power to start larger generators (of several MW capacity), which in turn can be used to start the main power station generators. There are several different units that are required for different plants, as well as well as several different methods of procurement of black start services, all of which are outside the scope of this document, but can readily be found on the internet.
In a nutshell, black start is the procedure to recover from a total or partial shutdown of the transmission system which has caused an extensive loss of supplies. This entails isolated power stations being started individually and gradually being reconnected to each other in order to form an interconnected system again. Often hydroelectric power plants are designated as the black-start sources to restore network interconnections. A hydroelectric station needs very little initial power to start (just enough to open the intake gates and provide excitation current to the generator field coils), and can put a large block of power on line very quickly to allow start-up of fossil-fuel or nuclear stations.
One of the main concerns in this country is the electrical grid. Without it we will be back in the 19th century, and millions will die. The government knows that the electrical grid is currently a soft target, and needs to be hardened. The industry has had people working on the hardening of the grid, but it is a very expensive and arduous task that will take a very long time if it is not put at the forefront of things we need to change immediately in this country. There have been some steps taken by individual groups within the matrix that makes up all the interconnects, but time and again it is proven that we are still vulnerable. The reason that black start facilities are so important is because they are the last line of defense. If they cannot come online and do their job, there will be no restoration. You don’t hear much about the idea of a black start or the facilities, but I assure you that our enemies know about them. Information on procedures, locations, equipment being used, etc. can all be found online by a savvy user. If terrorists were to stage an attack on the national power grid via Cyber attacks, as well as physical attacks, we would be fools to think that they would not attack the black start plants first, or surely have a plan to attack them as secondary targets. We have also seen reports where energy providers are talking about the recovery times due to a lack of replacement parts. There are many areas that need to be looked at when it comes to the national power plan and the grid. Black start facilities are going to play a critical role, and really need to be hardened immediately. Our grid will only be as strong as its weakest link. When we hear the media talk about the security of the grid, it is always a discussion driven by cyber security. While that is also important, we have seen our enemies in the middle east resort to guerilla tactics, and often the simplest and most devastating methods of attack. Often, the simplest answer is the best one.