Con Ed Study Details Projected Climate Impacts on Energy Systems

December 20, 2019

By Earth Institute

Extreme heat, coastal storm surge, inland flooding, and more violent storms will have significant impacts on the energy systems of the New York City area in the 21st century, according to a report issued today by the utility Con Edison. The report, developed in collaboration with Columbia University’s Lamont-Doherty Earth Observatory and the consulting firm ICF, evaluates the effects that expected climate change will have on current infrastructure, design specifications, and procedures. It says the company’s electric, gas, and steam systems will all be subject to increased flooding; the electric system will also be challenged by periods of sustained heat. Among the study’s findings: an increase in days when the heat index will reach or exceed 103 degrees, from two days a year now to anywhere from seven to 26 days a year by 2050.

The 36-month study, authorized by the New York State Public Service Commission as part of a collaborative venture created after Superstorm Sandy, describes historical and projected climate changes across Con Edison’s service area in New York City and Westchester County.

con edison worker

A new report explores climate-driven hazards that New York City area utility Con Edison will face in coming years. (Image courtesy Con Edison)

Lamont-Doherty climatologist Radley Horton, a coauthor of the study, said, “Con Edison took on some of the most vexing and pressing questions in climate science. They include how different climate variables like heat and humidity will interact in the future; how sequences of extreme weather might change; and how can we go beyond climate models to ask what a plausible worst-case scenario looks like for underappreciated hazards like extreme heat and extreme precipitation.”

To account for uncertainties in climate projections, the study considered a range of potential futures, reflecting both unabated and reduced greenhouse gas concentrations through time. It also evaluated extreme “stress test” scenarios. The analysis identified the most significant as sea level rise, coastal storm surge, inland flooding from intense rainfall, hurricane-strength winds, and extreme heat.

While Con Edison already uses a range of measures to deal with bad weather, the study is designed to guide the company’s strategies to strengthen its systems against the increasingly harsh events expected in the future. The report estimates the company might need to invest between $1.8 billion and $5.2 billion by 2050 on targeted programs to protect its electric, gas, and steam delivery systems against such events. The company will further evaluate future strategies and costs by developing 5-, 10-, and 20-year plans. Con Edison typically invests approximately $3 billion every year overall in its energy infrastructure.

Following Superstorm Sandy, the company invested $1 billion over four years on upgrades meant to prevent repetition of the failures during that storm. The measures have included stronger, tree-branch-resistant overhead cables and utility poles; reinforced entrances to tunnels carrying steam and gas mains to prevent flooding; and reconfiguration of electric grids in lower Manhattan so that areas with the greatest risk of flooding can be turned off without affecting surrounding blocks. After a pair of severe storms struck in quick succession in March 2018, it coordinated with Westchester County to spend an additional $100 million to fortify the electric delivery system in the areas that suffered the most devastation. As a next step, Con Edison will develop a detailed plan to implement the recommendations from the study.

Michael Gerrard, director of Columbia University’s Sabin Center for Climate Change Law, said the study “will provide a template for other utilities to undertake similar work, as they should.” Shortly after Superstorm Sandy, Gerrard and the Sabin Center pressed the Public Service Commission to require all utilities in the state to prepare for extreme weather events that could be worsened by climate change. Then, when Con Edison filed for a rate increase, the center intervened and negotiated an agreement for the company to hire outside experts to refine future climate scenarios and prepare plans to cope. The new study is the result.

“We recognize the global scientific consensus that climate change is occurring at an accelerating rate,” said Tim Cawley, president of Con Edison. “While climate change’s exact pace and effects are uncertain, the study provides a strong foundation upon which to plan, design, and invest in our energy delivery systems to better protect them and serve our customers.”

Media Inquiries: 
Marie DeNoia Aronsohn
marieda@ldeo.columbia.edu
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