A zero-combustion U.S. electric power scenario: September 1-7, 2021


Hourly & daily U.S. electric power supply if solar & wind electric generation is increased 7X


 

Hourly solar and wind electric generation MegaWatthours across the 48 contiguous U.S. States, September 1-7, 2021. U.S. Energy Information Administration chart. Times are Eastern zone.


  • wind-powered electric energy was greater overnight

  • solar-electric energy ramped-up mornings as wind declined

  • 24-hour daily charts show the effect of replacing all combustion electric generation with solar & wind


Overnight wind electric generation complemented mid’-day solar in the first seven days of September 2021, as shown in the chart above. Texas, the Midwest, Central/Great Plains, California and northwest States are regions of greatest windpower. Solar energy largest contributors are California and Texas.

This report examines the hourly impact of removing all combustion electric supply from the U.S. contiguous 48 States’ three electric transmission grids, and increasing wind and solar electric generating capacity by a factor of seven. Results assume that new wind and solar electric plants at existing sites, and perform the same as older units. Other new sites, such as off-shore windpower, may produce daily or seasonal production patterns which differ from existing sites.

Factors which may affect future bulk electric power transgrid transfers are not considered in this report. See Appendix for a list of these potential conditions.

U.S. States monthly electric generating totals by energy source may be compared at Linecurrents.live link to Energy Information Administration interactive maps and charts.

 

Notes

U.S. Energy Information Administration (EIA) Hourly Electric Grid Monitor is the source for data contained in the following charts. Please read EIA disclaimer in the Appendix.

Hourly charts in this report are based on Eastern time. Compared to local time at generator sites, hourly MWhr results are shifted to later in the day if the generator is not in the Eastern time zone:

1 hour: Central time zone - Midwest, Great Plains, Texas
2 hours: Mountain time zone
3 hours: Pacific time zone - Northwest, California


 

September 1-7, 2021
U.S. hourly electric power supply summary

Natural gas and coal combustion contributed the largest share of electric generation for the September 1-7, 2021 period.

Hourly electric generation from combustion and non-combustion energy sources. U.S. Energy Information Administration chart.


Electric generation from combustion and non-combustion energy sources. Linecurrents.live chart, U.S. Energy Information Administration data.


 

September 1, 2021
U.S. non-combustion & total hourly electric supply

Total U.S. hourly generated electric energy supply is shown by the gray line in the following series of daily charts. Total includes includes wind, solar, hydroelectric and nuclear shown by colored areas, as well as natural gas, coal, petroleum and other. MWhrs imported via electric transmission lines from Canada and Mexico are not included.

 

Linecurrents.live chart, U.S. Energy Information Administration data. Times are Eastern zone.


 

September 1, 2021
7X wind & solar

In the following examples, actual hourly U.S. contiguous 48-States solar and wind electric energy supplies are multiplied by 7.

These non-combustion energy sources, combined with existing nuclear and hydroelectric power generating capacity, would have been adequate to replace combustion generation sources for most hours of September 1. Overnight windpower and mid’-day solar energy oversupplies, if stored in batteries or other systems, could be released during the early-evening shortage.

Linecurrents.live chart, Energy Information Administration data. Times are Eastern zone.

 
 

 

September 2, 2021
7X wind & solar

If U.S. 48 contiguous States’ wind and solar electric energy generation were each increased by 7 times, these sources combined with existing nuclear and hydroelectric power generating capacity would have been adequate to replace combustion generation sources for most hours September 2. Oversupply stored in the afternoon could be released during the early-evening shortage.

 

Linecurrents.live chart, Energy Information Administration data. Times are Eastern zone.


 

September 3, 2021
7X wind & solar

Nuclear, hydroelectric, and 7X wind/solar electric energy would be inadequate to replace combustion electric generation after 4 PM Eastern September 3, 2021. Solar energy oversupply stored late-morning is insufficient to fill the evening electric generation shortage.

Linecurrents.live chart, Energy Information Administration data. Times are Eastern zone.


 

September 4, 2021
7X wind & solar

After strong performance September 1 and 2, windpower declined September 3 and 4. Wind and solar electric supply is unable to replace combustion generation all hours except late morning in the September 4 wind/solar 7X plus existing nuclear and hydroelectric generating scenario.

 

Linecurrents.live chart, Energy Information Administration data. Times are Eastern zone.


 

September 5, 2021
7X wind & solar

Windpower declined for third a straight day, and is unable to supply overnight electric demand. The 7X wind/solar plus existing nuclear and hydroelectric generating scenario is adequate to replace combustion electric generation for only a few late-morning hours.

Linecurrents.live chart, Energy Information Administration data. Times are Eastern zone.


 

September 6, 2021
7X wind & solar

Another low production day for windpower across the U.S. A recovery began late evening.

Linecurrents.live chart, Energy Information Administration data. Times are Eastern zone.

 

 

September 7, 2021
7X wind & solar

Windpower recovered to its September 1-2 strength in the 7X wind/solar plus existing nuclear and hydroelectric generating scenario. Energy storage systems could shift overnight wind and mid’-day solar oversupplies to fill the evening shortfall.

Linecurrents.live chart, Energy Information Administration data. Times are Eastern zone.


 

Regional hourly windpower:
Texas & California have the most consistent daily pattern

- - - - -
Note
: actual hourly electric generation data are used in the next discussion. No multiplier has been applied.
- - - - -

A pattern of greatest wind electric energy generation overnight in Texas and California regions was evident September 1-7, 2021. Charts below illustrate hourly windpower for the highest-producing U.S. windpower regions. Vertical gray lines indicate hour starting 12:00 AM. Times are Eastern zone.


 

Northwest

Windpower generation did not produce a daily high-low cycle in the region designated Northwest by the U.S. Energy Information Administration. The top windpower producing States in this region are Colorado, Washington, Oregon and Wyoming.


California

Strongest windpower generation September 1-7, 2021 occurred late-evening and overnight in California. Lower production September 4-6 is similar to the national trend.


Texas

Texas is the highest windpower producing U.S. State. The late-evening and early A.M. highest-output daily pattern was consistent September 1-7, 2021.


Central

Hourly wind electric generation September 1-7, 2021 did not develop a daily pattern in the Central region.


Midwest

Hourly wind electric generation September 1-7, 2021 did not reveal a daily pattern in the Midwest region.


Appendix

U.S. ENERGY INFORMATION ADMINISTRATION
HOURLY GRID MONITOR
Disclaimer: The information submitted by reporting entities is preliminary data and is made available "as-is" by EIA. Neither EIA nor reporting entities are responsible for reliance on the data for any specific use.


Factors which may affect future electric power transfers among U.S. regions

  1. inadequacy of existing transmission grid to move large amounts of electric power between regions

  2. new transmission line construction right-of-way acquisition and State/local jurisdiction issues

  3. States, Balancing Authorities and regions priorities for use of potential excess variable wind/solar electric energy:

    a) export to other BA’s or regions
    b) store and consume with no export
    c) consume electric energy when produced by electrification of transport, water and indoor space heating, and other fuel-switching to away from fossil fuels

  4. hydroelectric supply reduction due to drought

  5. nuclear electric supply reduction due to plant closures

  6. other