Climate change and the electric grid
November 2, 2021

Guest Contributor:
Ernie Hayden,
Founder/Principal at 443 Consulting

​In March 2021 the United States Government Accountability Office (GAO) released a report raising concerns about the impact of climate change and its effect on the electric grid. The GAO wanted to prepare this report to increase awareness of the US Department of Energy (DOE) and Federal Energy Regulatory Commission (FERC) leadership on the plight of the electric grid and risks posed by global climate change. Overall, the theme of this rather grim report is that climate change and its effects will cause problems throughout the US and global electric grid. Below are examples of the impacts caused by climate change that ultimately affect the electric grid.


According to an ABC News report, US hydropower generation is expected to decline 14 percent in 2021 when compared to 2020. The projected drops are concentrated in the Western US with California’s production expected to drop by nearly 50 percent.[1]

In the area of hydroelectric generation, the reduced availability of water makes generating electricity increasingly difficult. For instance, in California’s Lake Oroville reservoir – the state’s second-largest – water levels are rapidly falling. The water levels have fallen to the point where the Edward Hyatt Power Plant was shut down potentially affecting 750,000 households.[2]

An added concern is reservoirs can lose thousands of liters per second due to evaporation losses thus aggravating an already dire predicament.[3] Hence, with increased temperatures caused by climate change, the rate of evaporation and water loss is increased.

Lake Mead – which supplies the Hoover Dam hydrogenators in Nevada – has dropped so low that production is down by 25 percent. At Lake Powell on the Arizona-Utah border, US federal officials recently stated there is a 34 percent chance the Glen Canyon Dam will not be able to produce power at some point in 2023 if extreme drought persists.[4]

Impacts on other power plants

Declines in hydropower production can increase use of other energy resources such as natural gas and coal – with coal making the climate change problem even worse due to its emissions.

Power plants also require cooling water to run. Hence, if there is a lack of water, the plants cannot operate. Additionally, the water is increasingly warmer due to climate change thus reducing the thermal efficiency of the plants and reducing their power supply. This reduction on plant capacity increases the risk of black- and brownouts on the grid.

Transmission and Distribution

Warmer temperatures and heatwaves can negatively reduce the transmission capacity of power lines. Additionally, the increased temperatures can lead to more forest fires and even rapid death and decline of trees which then fall on and damage the transmission and distribution lines and towers themselves.

Climate change could also affect the ability of grid operators to transmit electricity. For example, warmer temperatures in the Southwest are estimated to decrease transmission line capacity by between 1.5 and 2.5 percent, according to a DOE report.[5]

Climate change could affect the ability of utilities to distribute electricity to customers. For example, higher temperatures could increase the likelihood of damage to power transformers on hot days, when electricity demand is at its highest.[6]

Power demand

Increased temperatures will result in increased electricity demand due to rising air conditioning load.

In Texas, the average annual temperature is expected to be 3 degrees warmer by 2036 than the average in the 1950s and the number of 100-degree days is expected to nearly double when compared with 2000-2018 – especially in urban areas. “A hotter Texas will threaten public health, squeeze the state’s water supply, strain the electric grid and push more species toward extinction.”[7]

A conclusion

The effects of climate change could cost billions, including the costs of power outages to utility customers and costs from storm damage, among others. Specifically, three reports reviewed by the GAO estimated that the average annual costs of severe weather-related outages to utility customers in the US totaled billions each year.

An additional impact on the electric grid attributed to climate change is the increase in installing renewable resources such as wind and solar in order to compensate for the shutdown of dams and reduced capacity of the transmission and distribution lines. However, building and bringing these added resources online – especially in geographic areas needing the power replacement – may not be installed on time.

In a word, climate change is with us to stay and the necessary solutions to these challenges are not readily available or inexpensive.

About the author

Ernie Hayden is a highly experienced and seasoned technical consultant, author, speaker, strategist, and thought leader with extensive experience in the power utility industry, critical infrastructure protection/information security domain, industrial controls security (ICS), cybercrime, cyberwarfare, and physical security areas. Hayden is currently the founder and principal of 443 Consulting, LLC. He has held roles as an ICS Lead at both Jacobs Engineering and BBA Engineering; executive consultant at Securicon LLC; and an information security officer/manager at the Port of Seattle, Group Health Cooperative (Seattle), ALSTOM ESCA, and Seattle City Light. Ernie is a frequent author of blogs, opinion pieces and white papers. He has authored a book Critical Infrastructure Risk Assessment – The Definitive Threat Identification and Reduction Handbook (Published by Rothstein) which has been awarded the ASIS International 2021 Security Book of the Year. He is also an accomplished wildlife and landscape photographer. Ernie lives in Anacortes, Washington with his wife Ginny and Cardigan Welsh Corgi, Meghan.



[2] “What water restrictions mean for California’s businesses,” Morning Brew, by Jamie Wilde, October 10, 2021.



[5] Electricity Grid Resilience GAO-21-346, page 16

[6] Electricity Grid Resilience GAO-21-346, page 17

[7] “Climate change is making state hotter, threatening public health, water supply and infrastructure,” Texas Tribune, by Erin Douglas, October 7, 2021.