Archive for July 19th, 2022

Part 2: Putting the “E” in EVs…

July 19, 2022

So, how much electricity will EVs eventually require?

In Part 1, we looked at current demand for electricity and concluded:

  • The U.S. currently consumes about 4 trillion kWh of electricity per year
  • About 1.5 trillion kWh (about 40% of the total) is consumed in residential use
  • A scant amount of electricity is currently being consumed for “transportation” … and, practically all of that is used by public transit systems.

Of course, EV demand for electricity will increase.

By how much?


Let’s look at our prior ballpark estimate:

A full “incredible transition” to EVs would increase consumer / residential electricity demand in the U.S. by over 40% (640 billion kWh / 1.5 trillion kWh = 43%)

Data, sources & calculations

  • in 2019, “there were almost 229 million Americans who have driving licenses
  • The 229 million collectively drove over 3.2 trillion miles.” Source
  • From what I can ascertain,  on average, a Tesla gets about 5 miles per kWh of stored charge. (e.g. a T3, 50 kwh battery gets 250 miles of range).
  • So, 3.2 trillion miles of driving requires 640 billion kWh of additional electricity.

What do other sources day?


The Energy Institute at the University of Texas analyzed the likely additional energy required by state for a full transition to EVs.


The UT-EI conclusion: On average across states, 30.9% more electricity will be needed to electrify EVs … with wide variability across states.

All States’ Data

The 30.9% translates to over 1.25 trillion kWh of added electricity required … almost equal to all of our current residential consumption of electricity.


In August 2021, the NY Times asserted (without attribution or analysis):

If every American switched over to an electric passenger vehicle, analysts have estimated, the United States could end up using roughly 25% more electricity than it does today.

Working the NYT’s estimate …

Their 25% — apparently based on total U.S. electricity consumption —  implies that we’ll need an additional 1 trillion kWh of electricity

The 1 trillion kWh of electricity is roughly equal to  66% of our current residential electrical consumption, (1 trillion / 1.5 trillion = 66%)


The Brattle Group is a research consultancy that “combines state-of-the-art analytical techniques and practical industry experience to answer complex economic, financial, and regulatory questions”.

Brattle analysts did a detailed “assessment of the investments needed across the electric power sector to support the deployment of 20 million EVs in the U.S. by 2030.

Brattle’s conclusion: 20 million EVs will add 60–95 TWh of annual demand and 10–20 GW of peak load to the system.

Taking the low end of Brattle’s range (60 TWH per 20 million vehicles) and scaling that number up to all 239 million vehicles currently on the roads …  717 billion kWh of additional electricity will be needed for a full “incredible transition” to EVs … with a high estimate of 1.135 trillion kWh of electricity required (equal to about about 75% of current residential electricity consumption).

239 million vehicles / 20 million = 11.95

11.95 x 60 TWH = 717 TWh

One Terawatt Hour is equal to 1 billion  Kilowatt Hours. Reference

So, 717 TWh = 717 billion kWh


So, how much electricity will EVs eventually require?

  • UT Energy Institute: 1.25 trillion kWh
  • Brattle Group (high): 1.135 trillion kWh
  • New York Times: 1 trillion kWh
  • Brattle Group (low): 717 billion kWh
  • HomaFiles estimate: 640 billion kWh

Our back-of-the envelop estimate was on the low side.

Looks like 1 trillion kWh is a reasonable (and easy to remember) estimate of the electricity load that an “a full “incredible transition” will add to the system … a 25% to 30% upper to our current levels.


Next up: So, where’s that electricity going to come from?

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