not sure if you meant to link a different chart - that chart is the electricity component of CPI-U (an inflation measure) meaning it's by definition not inflation adjusted - you'd probably want to find a chart of nominal values for electricity spending and adjust for inflation to see whether or not it's at an all time high. Which, recently it's run ahead of inflation because of the overall surge in demand and investment in upgrading aging infrastructure/adding new capacity, but long term it's pretty flat/down