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The Electrical Grid:
America’s Funnest Crisis
History of the Power Grid: Overview
Historical Perspective Materials Capacity Regulations
Early Transmission: 1900-1935
Electrification was largely a project of private industry
Due to transmission expenses, early electrification was confined to cities
1917: American Gas and Electric created first long-distance high-voltage transmission line
By 1930s, 90% of urban America had electricity
Transmission Takes Off: The 1930s
• Early 1930s: 90% of rural America without electricity
• 1935: Roosevelt creates Rural Electric Administration
• 1937: REA helps bring electricity to 1.5 million farms
• 1939; Price of one mile of rural line dropped from $2000 to $600. 25% increase in rural homes with electricity
REA Success
1942: 50% of rural areas had electricity
By the 1950s, electrification was brought to virtually 100% of rural areas
Materials: Early Transmission
Initially, transmission lines were supported by porcelain pin-and-sleeve insulators
Insulators were similar to those used for telegraph and telephone lines
Low practical capacity limit of 40 kV
Materials: 1900-1950
1907: Harold W. Buck invents a new disc insulator
Buck's invention allows practical insulators of any length to be constructed
These insulators allow for the use of higher voltages
Materials: 1900-1950
Side note: Increasingly present hydroelectric power is transmitted via power transmission lines
First US hydroelectric generator to supply the grid: Niagra Falls
Voltages increase throughout the 20th century to support the increasing hydroelectric supply
Materials: 1950-present
The trend toward flexibility - connected cap and pin insulator strings - began to distinguish Hi-Lines as we know them today. Insulators appeared in many forms as higher line voltages, heavier conductors, and wider tower spacing became common practice.
Underground Innovations: Literally!
Half of the capital expenditures for new transmission and distribution wires between 1993-2002 has been invested in underground wires
BUT: Underground transmission lines account for only .2% of total transmission lines installed in 2001
Underground lines cost approximately $1 million per mile
Capacity Factors:
1. Capacity of individual transmission lines
2. Capacity of the national grid
High-voltage transmission technology has improved
High-voltage transmission lines in the 20th century
0
200
400
600
800
1000
1200
1400
1900 1920 1940 1960 1980 2000
kV
Source: www.wikipedia.org, “Electrical Power Transmission”
Transmission capacity has grown in the last three decades
Source: Edison Electric Institute (www.eei.org)
But not as fast as demand
Source: Edison Electric Institute (www.eei.org)
Transmission Investment, 1975-2003
Source: Edison Electric Institute (www.eei.org)
Regulatory History
1935: Public Utility Holding Company Act
(PUHCA) 1978 – Public Utility
Regulatory Policy Act (PURPA)
1992 – Energy Policy Act (EPACT)
1935: Public Utility Holding Company Act (PUHCA)
The Problem:
-Huge holding companies control nation’s electricity
-Stock watering, fraudulent accounting
The Solution:
-Allow SEC to break up huge interstate companies
-Promoted smaller, vertically integrated companies in single geographic areas
1978: Public Utility Regulatory Policies Act (PURPA)
Helps non-utilities enter energy markets– Co-generators
– Small renewable energy facilities
1992: Energy Policy Act (EPACT)
Federal Energy Regulatory Commission (FERC) can order utilities to provide access to their transmission lines
This power expanded in 1996, so that utilities provide a fair rate for all users of transmission lines
The future - ?
Can we update the grid?
How will it be regulated?