Power grid

Power grid
United States Department of Energy, SVG version by User:J JMesserly · Public domain · source
Name	Power grid
Type	Infrastructure
Location	Global
Established	1880s

Power grid

A power grid is an interconnected system for delivering electricity from generators to consumers through transmission and distribution networks. It links Edison Electric Light Company, General Electric, Westinghouse Electric Company, Siemens, and Mitsubishi Electric era technologies with modern assets from Schneider Electric, ABB Group, Toshiba, Hitachi, and GE Vernova. Modern grids integrate legacy frameworks such as the Alternating current systems championed in the War of Currents with digital platforms used by operators like National Grid plc, PJM Interconnection, California Independent System Operator, Electric Reliability Council of Texas, and China Southern Power Grid.

Overview

A grid couples large centralized plants—historically dominated by entities including Tennessee Valley Authority, Bonneville Power Administration, Drax Group, and Électricité de France—with regional suppliers and urban networks run by utilities like Consolidated Edison, Tokyo Electric Power Company, State Grid Corporation of China, and Enel. Transmission arteries operate at voltages developed from experiments by Nikola Tesla, George Westinghouse, and Charles Proteus Steinmetz; distribution systems adopt standards promoted by institutions such as the Institute of Electrical and Electronics Engineers and International Electrotechnical Commission. Interconnection projects such as the North American Electric Reliability Corporation coordination and the European Network of Transmission System Operators for Electricity shape cross-border operations involving nations like United States, Germany, France, China, and India.

History and Development

Early systems trace to pioneers: Thomas Edison built the Pearl Street Station, while Nikola Tesla and George Westinghouse advanced AC transmission during the War of Currents. The growth of hydroelectric projects by James Francis and the rise of thermal fleets by companies like Commonwealth Edison and British Coal accelerated grid expansion through the 20th century. Postwar reconstruction, exemplified by programs such as the Marshall Plan, financed regional interconnections like the Soviet GOELRO plan and national utilities including Soviet Union state schemes. Deregulation waves in the 1990s led by actors including Enron and policy changes influenced by legislators in United Kingdom and United States transformed market structures and spawned independent system operators such as PJM Interconnection.

Components and Architecture

Key components include generation resources—thermal plants operated by firms like ExxonMobil subsidiaries, nuclear stations exemplified by Siemens, Areva projects, and renewables driven by developers such as Ørsted, Vestas, First Solar, and Goldwind—plus bulk transformers, high-voltage transmission lines, substations, distribution feeders, meters, and customer connections. Control centers use supervisory control and data acquisition platforms from vendors like Siemens, Schneider Electric, and ABB Group to manage assets originally influenced by technologies from Edison General Electric Company. Grid topologies range from radial urban networks used in city systems like New York City to meshed continental interconnections such as ENTSO-E across European Union member states and the multi-area North American grid interconnected via nodes managed by NERC regions.

Operation and Management

Real-time balancing of generation and load employs procedures and protocols codified by North American Electric Reliability Corporation and regional transmission organizations including California ISO and ERCOT. Market operations include day-ahead and real-time auctions conducted by exchanges such as Nord Pool, PJM Interconnection, and New York Independent System Operator. Grid operators rely on forecasting models developed in collaboration with research institutions like Massachusetts Institute of Technology, Imperial College London, and national labs including Lawrence Berkeley National Laboratory and National Renewable Energy Laboratory. Protection schemes reference standards from IEEE and IEC, while workforce training often involves programs at universities such as Georgia Institute of Technology and Tsinghua University.

Reliability, Resilience, and Security

Reliability frameworks are overseen by organizations like NERC and enforced through standards similar to those adopted by FERC. Resilience planning references events such as the Northeast blackout of 1965 and the Northeast blackout of 2003 to bolster redundancy, hardening, and islanding strategies used by utilities including Consolidated Edison and Pacific Gas and Electric Company. Cybersecurity draws on guidelines from National Institute of Standards and Technology and coordination with agencies such as Department of Homeland Security and European Commission cyber divisions, while physical security responses coordinate with entities like Federal Emergency Management Agency and national militaries during major disturbances.

Regulation, Economics, and Market Structure

Regulatory regimes vary: vertically integrated monopolies persisted under frameworks shaped by commissions such as the Federal Energy Regulatory Commission and the Office of Gas and Electricity Markets, while liberalized markets emerged under policy shifts in jurisdictions like United Kingdom and parts of Australia. Market designs—capacity markets, energy-only markets, ancillary service markets—are administered by bodies including PJM Interconnection, ISO New England, and Nord Pool. Financing models involve institutions such as the World Bank, European Investment Bank, and development banks like Asian Development Bank funding projects led by conglomerates including General Electric and Siemens.

Environmental and Technological Challenges

Decarbonization targets set by accords such as the Paris Agreement and national policies in Germany (Energiewende), China (Five-Year Plans), and United States impact generation mixes, driving rapid deployment of wind, solar, and storage from companies like Vestas, First Solar, and Tesla, Inc. Batteries, hydrogen initiatives from firms such as Air Liquide and grid-scale projects promoted by research centers like National Renewable Energy Laboratory address intermittency. Grid modernization features smart meters from vendors like Itron and advanced inverter standards influenced by IEEE 1547, while transmission expansion confronts siting disputes involving local governments and environmental NGOs like Greenpeace and World Wildlife Fund.

Category:Electric power infrastructure