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The technology by which we receive our electrical power is the first place to look, as breakthroughs in production of electricity directly from renewable wind and solar resources—without requiring combustion of fuels—have provided a lowest-cost option for instantaneous production of electricity in many instances.

The U.S. Energy Information Administration reports (Figure ET-14) that between 2018 and 2024, addition of new instantaneous power generation capacity by renewable wind and solar has far outpaced additions from natural gas.

Capacity refers to the ability to produce power at the maximum sunlight or wind speed for which the solar panels or wind turbines are designed, or for the maximum burn rate for a gas turbine supplied with natural gas. Generation by source (Figure ET-15) shows how much of our electricity in the U.S. was actually generated by renewable wind and solar power versus natural gas and other fossil resources.

This plot shows strong and similar growth in both natural gas and renewable wind and solar power over the last 5–10 years. Natural gas is backing out coal as a source of power, often due to reduced costs. Solar and wind are increasing, while other renewables such as hydroelectric are reducing.

Comparison of increases in capacity additions versus actual amount of power generated over the period 2018–2023 indicates that wind and solar can only produce at about 25% of rated capacity—which is fully expected, because the sun does not shine at 100% intensity during the night or due to clouds during the day. Similarly, wind speeds vary due to weather and seasons.

In managing the electrical grid, renewable wind and solar are generally used as the source of electricity when they are available, as once built they do not require consumption of purchased fuel. Sunlight and wind are free. When available production of electricity exceeds the demand from the grid, some sources of power generation must be turned off, or curtailed, to prevent overload which would damage the grid.

Coal plants are large combustion furnaces which are difficult to turn down or turn off, whereas power from sunlight or wind can stop in less than one second due to weather conditions. Battery or other forms of electrical energy storage is expensive (Figure ET-16), especially for durations larger than 2–4 hours.

Natural gas can be used in large power plants that are not easy to turn down but would be most amenable to addition of carbon capture and storage, or in smaller peaker plant gas turbines which can be turned on and off more rapidly to provide the makeup power needed to augment the intermittency of wind and solar power. Natural gas is available 24/7 from pipelines, except in the event of a hard freeze if protections were not enacted. Hard freeze can also stall wind turbines via their lubricants.

Generation of electrical power by natural gas has thus ramped up in proportion to wind and solar in order to balance grid production over the last 5 years.

So yes, there are many signs of energy transitions as we look to optimally use low-cost instantaneous electrical power from wind and solar resources when they are available, but also look to optimally supply the 24/7 demand for all forms of energy that U.S. consumers require—which has led to growth also in energy provided by natural gas.

Looking at total energy and not only electricity, renewables now supply up to 9% of total U.S. energy (Figure ET-17), with fossil resources comprising 83%.

Figure ET-14:     US Energy Information  Administration ( www.eia.gov ) 

  
Figure ET-15:  US Energy Information  Administration ( www.eia.gov ) 

Figure ET-16:  Cost of backup power from natural gas versus use of Long Duration Energy Storage (batteries or compressed air, etc).      
Reference:  McKinsey (2024).  

 
  
Figure ET-17:  US Energy Information  Administration ( www.eia.gov )