Electricity in the 1970s

Electricity generation in the 1970s showed an interesting pattern of changing generation sources.

With increased air quality and smog concerns (Clean Air Act of 1970) and relatively low oil prices electricity was increasingly generated using petroleum during the late 1960s through the 1970s.  This meant that the proportion of electricity generated using coal dropped considerably during this time period.

The Oil Crisis of 1979 and rising oil prices put an abrupt stop to this pattern.  Amid the fears of oil price shocks and supply disruptions there was an intentional shift to electricity generation from coal and a build-up of coal-fired power plants.  Since this time petroleum has constituted a small and declining share of electricity generation.

This pattern can be clearly identified in the Washington & Jefferson College Energy Index.

• In 1965 coal accounted for 21.5 percent of primary energy consumption while petroleum accounted for 43 percent in the same year.  
• By 1978 coal had fallen to 17.2 percent of all energy consumed while petroleum had climbed to 47.6 percent of usage.  
• In 1985 (following the 1979 oil crisis) coal had rebounded to account for 23 percent of primary energy consumption and petroleum had fallen to 40.5 percent of energy used.

The energy index values from this time period are telling.

• In 1965 the value was 90 as domestic coal was used to produce electricity.
• In 1978 the value had fallen to 77.5 as oil that was increasingly used for electricity production was sourced outside the US.
• In 1985 the value was back to 85.6 with the shift back to domestic coal usage.

In later posts we will cover a similar situation that is occurring now as electricity is increasingly generated using natural gas as the primary energy source.