Floods, fires, heat waves and storms threaten grid

Severe weather linked to climate change increases the risk of temporary shutdowns of power plants and damage to key infrastructure, including transformers and electricity distribution systems, according to a new Department of Energy (DOE) report.

The DOE released its report, ‘U.S. Energy Sector Vulnerabilities to Climate Change and Extreme Weather,’ on July 11. The report comes on the heels of President Obama’s recently-announced effort to better confront greenhouse gas issues.

The report says 2012 was both the warmest year on record in the contiguous United States and saw the hottest month since the country started keeping records in 1895. The implications for America’s power system include:

•Increased risk of temporary partial or full shutdowns at coal, natural gas, and nuclear power plants because of decreased water availability for cooling and higher ambient and air water temperatures. A study of coal plants, for example, found that roughly 60% of the fleet is located in areas of water stress.

•Reduced power generation from hydroelectric power plants in some regions and seasons due to drought and declining snowpack.

•Risks to energy infrastructure located along the coast from sea level rise, increasing intensity of storms, and higher storm surge and flooding.

•Higher air conditioning costs and risks of blackouts in some regions if the capacity of existing plants does not keep pace with the growth in peak demand.  An Argonne National Laboratory study found that higher peak electricity demand as a result of climate-related temperature increases will require an additional 34 GW of new generation capacity in the western United States alone by 2050, costing consumers $45bn. This is roughly equivalent to more than 100 new power plants, and doesn’t include new power plants needed to accommodate population growth.

Severe weather affects energy in many ways

The DOE report notes that severe weather patterns linked to global warming affect the energy sector in many ways.

“Changes in climate have the potential to significantly impact U.S. energy security by forcing the present aging energy system to operate outside of the ranges for which it was designed,” according to the 80-page report.

In August 2012, Dominion (NYSE:D) temporarily idled one reactor unit at its Millstone station in Connecticut because of the temperature of the intake cooling water.

A similar problem resulted in temporarily reduced output in the summer of 2010 at nuclear plants in Pennsylvania and New Jersey at nuclear plants owned by Public Service Enterprise Group (NYSE:PEG) and Exelon (NYSE:EXC).

Heat waves tend to be tough on power generation. In the summer of 2011 consecutive days of triple-digit heat and record drought in Texas resulted in the Electric Reliability Council of Texas (ERCOT) declaring power emergencies due to a large number of unplanned power plant outages.

Decreasing water availability for concentrating solar power plants could decrease potential generation capacity at those units, the report indicates.

On the hydro front, water levels in Nevada’s Lake Mead in September 2010 dropped to levels not seen since 1956. This prompted the Bureau of Reclamation to reduce Hoover Dam’s generating capacity by 23%.

Also in Nevada, NV Energy (NYSE:NVE) abandoned a proposed plan in 2009 for a 1,500 MW coal-fired power plant (Ely Energy Center) that would have used more than 7.1 million gallons of water per hour.

Also reduced river levels can complicate fuel delivery to certain power plants, such as barge movements of coal. This was the case in the summer of 2012 when low river water depths disrupted barge traffic along the Mississippi River, the report notes.

On the cooling water front, the report urges increased implementation of less water intensive technology and use of non-traditional supplies, such as municipal wastewater or brackish groundwater.

There is also the risk that flood waters can pose to power generation, the DOE report notes. In June of 2011 Missouri River floodwaters surrounded Fort Calhoun Nuclear Power plant in Nebraska. The nuclear reactor had been shut down in April 2011 for scheduled refueling, but the plant remained closed during the summer due to persistent flood waters. It has yet to return to service.

On the wires front, electric transmission and distribution systems carry less current and operate less efficiently when ambient air temperatures are higher. That’s in addition to the increased risk of physical damage associated with severe storms, the report notes.

Wildfires also pose a risk to the transmission grid.

In the summer of 2011, severe drought and record wildfires in Arizona and New Mexico burned more than one million acres and threatened DOE’s Los Alamos National Laboratory as well as two high voltage lines transmitting electricity from Arizona to approximately 400,000 customers in New Mexico and Texas

The report also urges greater data gathering about energy sector vulnerabilities

The report was drafted by the DOE’s Office of Policy and International Affairs (DOE-PI) and the National Renewable Energy Laboratory (NREL). The coordinating lead author and a principal author was Craig Zamuda of DOE-PI. The report draws upon input from other federal agencies including EPA and National Oceanic and Atmospheric Administration (NOAA).

About Wayne Barber 4201 Articles
Wayne Barber, Chief Analyst for the GenerationHub, has been covering power generation, energy and natural resources issues at national publications for more than 20 years. Prior to joining PennWell he was editor of Generation Markets Week at SNL Financial for nine years. He has also worked as a business journalist at both McGraw-Hill and Financial Times Energy. Wayne also worked as a newspaper reporter for several years. During his career has visited nuclear reactors and coal mines as well as coal and natural gas power plants. Wayne can be reached at wayneb@pennwell.com.