Building Better Power Grids

Wednesday, May 30, 2018

Earthquakes, tornadoes, volcanic eruptions, ice storms, solar storms, brush fires, cyberattacks—these are just some of the events that can disrupt or incapacitate an electric grid. But for many countries in the region, it is the threat of hurricanes that looms the largest, especially with the start of the Atlantic hurricane season on June 1 and last year’s brutal storms still fresh in people’s memories. The challenge is how to make the region’s power grids more resilient, so that they can withstand or recover from increasingly severe storms.

One important fact to remember: It’s impossible to eliminate power outages 100 percent, no matter how much money or effort a country invests in its electric grid. That’s according to a consensus report called “Enhancing the Resilience of the Nation’s Electricity System,” issued last year by the U.S. National Academies of Sciences, Engineering, and Medicine.

“To increase the resilience of the grid,” the report stated, “the nation must not only work to prevent and minimize the size of outages, it must also develop strategies to cope with outages when they happen, recover rapidly afterward, and incorporate lessons learned into future planning and response efforts.”

Dr. Gary Jackson, an independent energy consultant in the Caribbean, framed the issue of resilience this way: “It’s more than just the wires that connect the poles. It’s building a resilient framework so that countries have the ability to recover in the shortest possible time.”

Recovery, in fact, is at the very core of resilience. The Oxford dictionary defines resilience as “the capacity to recover quickly from difficulties; toughness” or, alternatively, “the ability of a substance or object to spring back into shape; elasticity.” Both of those aspects—toughness and elasticity—come into play as countries in the region look to harden their grids against storms and rethink the way they deliver electricity to make the power system more flexible. (See related story in this issue.)

This is hardly a new issue, especially to the Caribbean Community (CARICOM), but it has been gaining steam in recent years, as the effects of climate change have produced more powerful and more frequent storms.

“Last year’s hurricanes caught everybody’s attention,” said Dr. Devon Gardner, who manages the CARICOM Secretariat’s Energy Programme. At a meeting this April in Guyana, the Caribbean countries’ energy ministers decided to form an Energy Resilience Task Force to focus on this aspect of hurricane preparedness. (See sidebar.)

In some countries, electric utilities have already made significant strides in their ability to restore power after a storm. Since Hurricane Ivan hit Jamaica in 2004, for example, the local utility—Jamaica Public Service Ltd. (JPS)—has been able to reduce its restoration rate from six weeks to a week and a half, according to Gardner. That’s the estimated time it would take to restore power to the vast majority of customers after extensive damage.

Unfortunately, some of the utility’s progress on this front has come at the cost of extensive experience. According to Gardner, tropical storms and hurricanes have hit Jamaica often enough that individuals at JPS have been able to repeatedly study the power system’s shortcomings and vulnerabilities and make corrections and adjustments after each storm. The utility does thorough disaster planning, including drills and simulations, to anticipate different scenarios. (JPS shared some of its experiences with other member states during a roundtable discussion last October, Gardner said.)

Strong yet Vulnerable

Traditional power grids are complex networks made up of many interconnected components, ranging from rock-solid centralized power plants to overhead electric lines that can snap in a high wind.

“A large diesel or heavy fuel oil power plant is resilient,” said Christopher Burgess of the Rocky Mountain Institute (RMI). However, he added, that system cannot deliver electricity without transmission and distribution lines, “which are completely vulnerable.”

“Maybe your power station is fine, but is it really resilient if you have to wait months to get back on line fully?” asked Burgess, project director for RMI’s Islands Energy Program, which works in 13 Caribbean island countries to advance the transition to renewable energy. Another point of grid vulnerability, Burgess said: the fuel supply. If that gets cut off, as happened in Puerto Rico in the wake of Irma and Maria last year, even undamaged generators simply cannot operate.

Today, discussions about grid resilience often focus on making electric power systems less centralized and more modular with microgrids providing an additional level of protection. (See related story.) But back in the 1980s and even the 1990s, the emphasis was on expanding access to electricity, and large centralized power plants were the most cost-effectiveway to go, according to CARICOM’s Devon Gardner.

In a phone interview, Gardner talked about how priorities have evolved over the years. Once access to electricity had been achieved, the next steps were to improve reliability, stability, and quality, such as by reducing brownouts and flickering lights. In the early 2000s, with climate change taking on a higher profile, clean energy became an important new goal; then, with prices for indigenous sources of energy dropping, demands grew for cheaper clean energy. Now, at a time of better technology and urgent climate challenges, more attention is turning to making power grids more resilient.

While that’s starting to happen in some places, significant resources will be needed to accomplish that on a large scale, according to Gardner. For example, he said, as sensible as underground cables might seem, they can cost 14 times as much as overhead wires.

The costs of maintaining an electric power system already tend to be disproportionately high in small island states because they are unable to achieve economies of scale, Gardner noted. And every country, no matter how small, needs to generate enough power to meet baseload and peak demand, in addition to having backup generation and “spinning reserves” on tap to compensate immediately for power interruptions.

Power grids should be considered a public service obligation akin to roads, Gardner said, and strategies to increase resilience should be incorporated into countries’ integrated energy planning. He also stressed that resilience measures should be treated as climate change adaptations, eligible for global climate funding from the countries that bear the most responsibility for the problem.

Instead, according to Gardner, improving grid resilience is typically viewed as part of a utility’s responsibility to invest in modernization. The problem, he said, is that these types of investments will eventually be passed along to customers, and that is a large burden to place on ratepayers who already have some of the highest electricity rates in the world.