Electrical infrastructure

The Importance of Electrical Infrastructure

Until the 1960s, the electric system was a largely disconnected network of isolated generators. Today, utilities link their generating plants to provide power to a wide range of customers. Increasingly, this type of network has become a valuable resource for the economy and reliability of the electric system. The interregional "grid" replaced the isolated generators. Throughout history, electrical infrastructure has been vital to the growth and development of civilization.

Transmission network

Managing the reliability of the transmission network of the electrical infrastructure is an ongoing challenge. As millions of consumers turn on and off appliances and industrial equipment, the demand for electricity fluctuates constantly. To address this problem, 140 balancing authorities work to balance the supply and demand of electricity. They must maintain voltages within a specific range to prevent system collapse. Variations in voltage and frequency can cause equipment damage or even collapse. Therefore, balancing authorities play an important role in the reliability of the bulk electric system.

Electricity networks in Australia are typically thin and long, running from the north of Queensland and south of Tasmania, eastward through South Australia. In the early 20th century, electricity networks were primarily built by state governments, but interstate transmission interconnectors were constructed to share resources more efficiently. The NEM was formally formed in the late 1990s. Today, the NEM is composed of three large interconnected systems. Each is comprised of a number of smaller grids that are connected to each other through a network of interstate wires.

To achieve these goals, the distribution network must be modernized. This requires more investment than the transmission network. New generation technologies will enable consumers to generate and sell power on their own. An advanced grid will enable two-way power flow in the distribution system, as well as the development of self-generation opportunities for end users. But if modernization is to be successful, the transmission and distribution network must be upgraded, not just expanded. This requires extensive planning and coordination across multiple systems.

In addition to electricity distribution, the transmission network of electrical infrastructure must also include the right of way. These corridors are essentially tall poles that carry multiple wires. Transmission lines are necessary to move bulk electricity over long distances. These high-voltage lines are impractical to deliver directly to homes, as the power that is transmitted is very high. The voltage of the transmission lines is typically between 100,000 and 100 kV.

Substations

There are different types of transmission substations, ranging from simple "switching stations" with only a few circuit breakers to large facilities that cover a large area. Transmission substations can include several voltage levels and an extensive array of protection and control equipment. Modern transmission substations may be built using IEC Standards 61850. Read on to learn more about these important pieces of infrastructure. Described below are the different types of transmission substations and their functions.

When choosing a location for a substation, many factors must be considered, including sufficient land area, clearances for electrical safety, and access for large apparatus. Substations are sometimes built using gas-insulated switchgear, which saves on space but is often more expensive. Substations built in coastal areas may require an elevated structure to protect sensitive equipment and provide additional space for expansion. In addition, environmental effects must be considered.

Moreover, as the world continues to move toward a sustainable energy future, the role of substations in the power grid must change. As the role of electrical infrastructures shifts to renewable resources, utility managers must adapt to new technologies to ensure continued service. For instance, introducing fibre-based IEC 61850 communications is an excellent way to extend the life of an existing substation. However, the need for a new generations within the distribution grid may also force substation construction.

Another important role for substations is in the management of voltage. When a voltage exceeds its capacity, a switch will trip and disconnect the load from the feeding point. In some cases, the circuit breaker will also trip in such a situation, which isolates the fault point from the rest of the system. Because switching in substations requires high-voltage equipment, maintenance is essential to maintain the integrity of the system.

Transmission lines

In the field of electrical infrastructure, transmission lines refer to a single or multiphase cable that carries electric power. These cables are typically higher in voltage, ranging from 69,000 volts to more than 40,000 volts. Distribution lines, on the other hand, carry lower voltages to consumers, including homes and businesses. The voltage and current of electricity carried by transmission lines determine the type of tower and conducting wires used, as well as the visibility of the entire system.

The conductors of transmission lines are generally electrically insulated, as are the transmission structures themselves. Transmission line engineers' primary concern is to reduce voltage drop over long distances, and a higher voltage requires more insulation between conductors and the ground. In order to achieve this goal, transmission lines often feature stranded conductors, which are known as "silks."

Subtransmission lines carry a lower voltage and are typically overhead. They may also be buried underground if space is limited. The right-of-way for these lines is very important. Trees growing in close proximity to transmission lines can short out the cable, causing a dangerous electrical current to flow through the ground. These outages can affect hundreds of thousands of customers, so PSE&G actively maintains the area around transmission lines to prevent any potential hazards.

New applications for transmission lines usually include a detailed analysis of the electric and magnetic fields present on the line. The utility or electrical engineering consultants perform these analyses with the use of modelling software. Some state public utility commissions access software provided by the Bonneville Power Administration that analyses electric and magnetic field levels in transmission lines. These reports, however, usually do not comment on the impact of magnetic or electric fields on human health. They may refer you to state health departments for more information.

Bulk-power transmission network

The term bulk-power system refers to the facilities and control systems for the operation of an interconnected electric-energy transmission network. It includes electric energy from generation facilities that are needed to maintain transmission reliability. It does not include local distribution. A bulk-power transmission network must balance supply and demand, and it must be monitored around the clock to ensure system reliability. This type of network is an essential component of an integrated electric energy transmission network.

The bulk power system relies on long supply chains, with many non-domestic sources and links. These long supply chains have increased reliance on overseas manufacturers and foreign suppliers. The bulk of power, which flows through the network, is concentrated in the National Assembly, which has 90 members. The bulk of power is transferred across international boundaries to reach wholesale customers. The system is also linked to distant bulk power generation facilities. In the US, bulk-power transmission networks are monitored by the North American Electric Reliability Corporation (NERC).

A transmission network also consists of distribution lines and high-voltage distribution lines. A transmission network carries large volumes of high-voltage electricity across long distances. These transmission lines are connected to high-voltage substations and customers. The combined network is referred to as an electrical grid. Further, it connects electric generating facilities, a utility, and a customer. A transmission network is the key component in delivering electricity.

The Western Interconnection is composed of two primary interchange voltages of 500 kV AC at 60 Hz. A third network, the Texas Interconnection, is used for power interchange between grids. The two network infrastructures serve the western United States, but little electricity is exchanged between them. The Western Interconnection is comprised of high-voltage transmission equipment and generating resources. It does not include local distribution systems, which typically operate at lower voltages.

Energy storage methods

As renewable energy sources become more prevalent, energy storage on a large scale has become a hot topic. While pumped storage is an established technology, other megawatt-scale technologies are under development. These technologies are intended to provide dispatchable capacity as demand dictates. In order for storage to be an effective complement to renewable energy sources, it must be able to meet the demand for several days. Batteries are increasingly marketed as an effective way to store excess solar power during the day, helping to reduce peak demand in the evenings.

In the United States, over 30 gigawatts of pumped storage capacity is currently operational. In the United Kingdom, 900 MW of utility-scale battery storage capacity has been installed, with the potential for further growth. Utility-scale battery storage costs are expected to fall to $200 per kWh by 2023. By 2040, there will be an average of four GW of battery storage capacity installed in the U.S., with most installed in Europe and Japan.

California and Oregon have set targets for energy storage, with utilities there required to install at least five megawatt-hours (MWh) of battery storage by 2020. PGE is proposing to install up to 39 gigawatt-hours of storage at multiple locations. This project will cost between $50 million and $100 million. In Massachusetts, meanwhile, utilities have issued a target of 200 MWh by 2020. Finally, New York resolved to install 550 MWh of battery storage by 2030.

The capital costs of electric energy storage technologies are higher than those of natural gas generators, but batteries are significantly cheaper and are now affordable. This type of energy storage may be beneficial for utilities in deregulated electricity markets, where ownership of energy storage facilities is limited to transmission companies. The lack of decoupling between transmission companies and electricity production limits their market penetration. In some states, utility rates are tied to the volume of energy sold. As such, investing in energy storage could reduce the costs of building new transmission lines.