Electric power transmission

Electric power transmission
Name	Electric power transmission
Uses	Bulk transfer of electrical energy
Related	Electrical grid, Power station, Substation

Electric power transmission is the bulk movement of electrical energy from generating sites, such as power stations, to Electrical substations. This interconnected network, often called the Electrical grid, forms the backbone of modern electrical supply systems. High-voltage transmission allows for efficient transfer over long distances with reduced energy losses, enabling regional power sharing and grid stability.

History

The development of modern systems began with early experiments in the late 19th century, including the work of Nikola Tesla and George Westinghouse in promoting Alternating current over Thomas Edison's Direct current systems. A pivotal demonstration was the War of the Currents, culminating in the success of the Adams Power Plant Transformer House at Niagara Falls powering Buffalo, New York in 1896. The first large-scale, high-voltage Alternating current line was built for the Bavarian Exhibition in 1891 by Mikhail Dolivo-Dobrovolsky and Oskar von Miller. The 20th century saw the rapid expansion of interconnected grids, such as the Tennessee Valley Authority and the UK National Grid, with increasing voltages to improve efficiency and capacity.

Technology

Primary technology involves High-voltage direct current and Alternating current Overhead power lines, supported by Utility poles and Lattice towers. Key components include Electrical transformers to step voltage up for transmission and down for distribution, Circuit breakers for protection, and Capacitors for Reactive-power compensation. Substations, like those managed by National Grid plc, house this equipment. Insulator (electricity)s, often made of Porcelain or Polymer, prevent current leakage from conductors. Underging and Submarine power cables are used in sensitive or aquatic environments, with technologies from companies like ABB Group and Siemens.

Grid operation

System operation ensures stability and reliability, managed by entities like the North American Electric Reliability Corporation and European Network of Transmission System Operators for Electricity. Load balancing (electrical power) matches generation from sources like Nuclear power plants and Wind farms with consumer demand. Frequency must be maintained within strict limits (e.g., 60 Hertz in North America, 50 Hertz in Europe). Operators use Supervisory control and data acquisition systems for real-time monitoring and control, coordinating with Independent system operators such as CAISO and PJM Interconnection. Contingencies for events like the Northeast blackout of 2003 are managed through grid codes and automatic systems.

Environmental impact

Infrastructure affects landscapes and ecosystems, with concerns over Electromagnetic fields, visual impact of towers, and land use. Construction can disrupt habitats, while Corona discharge from lines produces trace gases. Mitigation includes using HVDC for more efficient point-to-point links, as seen in projects like the Pacific DC Intertie, and routing lines carefully to avoid sensitive areas like Yellowstone National Park. There is ongoing research into the effects on wildlife, including birds like the Bald eagle. The shift to renewable sources, such as connecting offshore Wind power in Denmark, also presents new transmission challenges and environmental assessments.

Economics

The sector is capital-intensive, involving major investments by utilities like Électricité de France and American Electric Power. Costs include construction, right-of-way acquisition, maintenance, and transmission losses. Markets and pricing are often regulated by bodies such as the Federal Energy Regulatory Commission in the United States or Ofgem in Great Britain. Economies of scale favor high-capacity lines, while projects like the Itaipu Dam transmission lines demonstrate international investment. The Energy Policy Act of 2005 in the U.S. aimed to improve grid planning and cost allocation.

Future developments

Innovation focuses on increasing capacity, efficiency, and resilience. Smart grid technologies, promoted by initiatives like the European Union's Horizon Europe, integrate digital communication for better control. High-temperature superconductor research at institutions like Massachusetts Institute of Technology aims to reduce losses. Expanding HVDC networks, such as proposed links like EuroAsia Interconnector, will facilitate integration of remote renewable energy from places like the Gansu Wind Farm. Concepts like Global energy grid and advancements in Power electronics from companies like General Electric are also shaping the future landscape.

Category:Electric power