Keeping the lights on in a warming world
This post is the second in our Climate Change Adaptation series.
Ensuring the resilience of power grids during extreme events—whether those occurring now or those that are influenced by future climate change—is much on the mind of legislators, regulators and power companies these days. The warning signs are all around us. Record-breaking storms and floods in the UK this winter left more than half-a-million homes without power. This spring, the country’s worst drought in four decades forced the Brazilian government to provide $5 billion worth of aid to their hydropower-dependent electricity sector.
We expect electricity to be available at the flip of a switch, 24/7/365. When momentary local power outages occur, we may be annoyed and inconvenienced. When extreme events like Hurricane Sandy or Typhoon Haiyan strike, entire regions can be put out of business for days, weeks and even months, resulting in massive destruction, loss of life and widespread economic harm.
The effects of extreme weather are already the leading cause of grid disturbances in the United States and other parts of the world, and this is expected to worsen as our global climate changes. In a 2012 special report, Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation, the Intergovernmental Panel on Climate Change (IPCC) noted that “a changing climate leads to changes in the frequency, intensity, spatial extent, duration, and timing of extreme weather and climate events…” Extreme weather events (eg, hurricanes) as well as extreme climate events (eg, long-term drought or heat waves) can and do affect electricity production, transmission, distribution and demand—as well as the supply chains that provide fuels, equipment and other inputs to the electricity enterprise.
How much more extreme will weather get in a changing climate? Last year, in the aftermath of Sandy, we worked with partners including the US National Center on Atmospheric Research and the Long Island Power Authority to analyse the effect that the same storm might have had in a warmer world. What we found was alarming. In 2012, Sandy left some residents of Long Island without power for weeks, Twelve distribution substations were flooded by the 4.5 meters of storm surge. In 2050, according to our models, the same storm against the background of warmer oceans and higher sea levels would cause 7 meters of storm surge. In 2090, we’re looking at 9 meters. The ensuing flooding would more than double the number of substations flooded, affecting more people and requiring longer recovery times.
Defining the costs of implementing measures that increase grid resilience is relatively straightforward. Defining the benefits, however, is much more difficult, especially given the inherent uncertainties about severe weather events. But figures such as the $5 billion Brazil paid show that the costs saved could be substantial indeed.
We need to take a risk management approach in making decisions about how much to invest in enhancing grid resilience, addressing the following questions:
- What storm hazards should we plan for?
- How will a changing climate alter the frequency, intensity and location of extreme weather events?
- How could the electric grid be impacted?
- What are the consequences of those impacts?
- What additional steps can we take to prevent damage to the grid and restore service as quickly as possible?
- How can we minimize the consequences of electric grid failure?
- What are the investments with the greatest return?
DNV GL launched an initiative in 2013 to create a power sector-specific framework for identifying, quantifying and measuring climate change risk to electricity supply, delivery and end uses. The framework informs utility managers and public sector decisionmakers about the costs and benefits of taking measures to enhance grid resilience. Specific actions such as hardening infrastructure to better withstand impacts, smart grids that can detect incipient problems and automatically take actions to keep electricity flowing and installation of microgrids and other redundant supply options are evaluated and then ranked according to their cost-effectiveness in meeting predefined criteria such as maximizing load served by the electricity system.
Improving grid resilience is a necessity, not only in the event of a rise in emissions going forward, but also simply to manage the effects from emissions to date. Even if our global society manages to develop a workable plan to substantially reduce emissions,adaptation will be necessary because we are already committed to a certain amount of climate change due to the long residence time of greenhouse gases in the atmosphere.
We look forward to working with electricity enterprise stakeholders throughout the world to help them understand climate-related risks, and to identify cost-effective investments for avoiding or minimizing risks.