Two devastating blows were dealt to the Caribbean Islands in September 2017, in the form of Category 5 hurricanes that caused massive human and economic losses.
What does it mean for infrastructure to be resilient? The most critical element is to lower its chance of failure. Also, should failure occur, resilient infrastructure is planned and implemented in a way that keeps negative consequences at a minimum, with the ability to recover rapidly from failure.
Based on this definition, the traditional, centralized electrical grid and water treatment and supply systems are far from resilient. Their hierarchically networked nature means disruptions in one area can take down a significantly larger part of the system, amplifying the human and economic loss during and after disasters. When failure does occur in the typical electrical grid, the standard approach is to rely on backup diesel generators, and since centralized water treatment and supply systems depend on the electrical grid,these systems are dependent on the same generators.
The lesson we learned with Katrina and now Irma and Maria is that this is not a backup plan conducive to rapid recovery. While we had millions of gallons of diesel fuel, there was often no electricity to pump the fuel out of centralized storage tanks. Even when one managed to extract the fuel out of the tanks, there was limited capability to transport it. In many cases, the generators themselves were water logged, old, or otherwise non operational. Battery systems were utilized in some cases, but these tend to be of short-term duration, ranging from 30 minutes to a maximum of three hours.
Figure 1: Key to infrastructure resilience is providing as many fallback plans as possible to prevent system failure by diversifying the sources and technologies for providing energy and water. Rebuilding centralized systems with single points for system is not the answer.
Resilient infrastructure minimizes the chance of service interruptions by having multiple interlinked yet independent fallback options to guard against failures that can otherwise lead to service interruptions. Having localized sources of energy and water that are close to or at the sites where they are needed also contributes to infrastructure resilience by improving efficiency and accessibility. Rebuilding the energy and water infrastructure using locally-available energy sources removes the dependency on a central point for energy and water access forever. For example, a localized, distributed system for energy, called “on-site hybrid distributed renewable energy generation,” utilizes multiple technologies (e.g., solar, wind, geothermal, hydropower) that can work together or independently. It cannot be remotely controlled, so it is cyber-secure. No fuel delivery is needed, so a compromised supply chain no longer becomes a problem. The generators can be combined with other renewables and battery storage, or even small propane generators or fuel cells. Larger electric generators from waste biomass, moving water, and geothermal can provide 24-hour power indefinitely. This makes these systems completely operational at all times under all conditions, ensuring people’s access to energy and clean water from treatment plants during and after disasters.
Tackling the loss of energy and water access on a local level through careful planning of resources that are available on site, in particular renewable energy and water, for the right uses can speed up the recovery process. By rebuilding the energy and water infrastructure against extreme weather events, reconstructing post-disaster can not only serve in the short-term but also set up communities for long-term sustainability and growth.
In looking at reconstructing these island communities, it is important to remember immediate relief efforts, when hastily implemented, can create unintended obstacles to long-term growth and sustainability. With that in mind, the first order of business for island communities is to assess what needs to be in operation at all times during extreme weather events. This critical water and energy infrastructure can often be supported with on-site hybrid distributed renewable energy generation.
One of the most essential functions during emergencies is communications – from cellular towers, government communications, to cameras. Another is overall functionality for first responders, including police, fire, and emergency health support. Other needs include pipelines and pumps for water, sewage, and fuels, as well as core functions at water and sewage treatment plants. Roadway signals and street lighting and signage are also critical to preventing gridlock and expeditiously moving first responders, and reconstruction and service crews. The same applies to railroad, seaport, and airport lighting and communications. While data centers have layered backup, many go down because diesel fuel suppliers cannot arrive in time to refill back-up diesel generator tanks.
In buildings, critical functions include WIFI, phone, security, and at least one elevator shaft. Operating rooms in hospitals, data centers within buildings, and sump pumps that prevent flooding must be able to function during disasters. In southern and northern climates where extreme temperatures may occur, functioning heating and cooling systems are essential to ensure minimally acceptable thermal comfort and to protect the health of vulnerable populations.
On a community level, powering selected strip malls that are geographically dispersed with ATM machines, refrigeration for food, and gasoline pump islands can help keep civil society functioning. In an effort to unburden local hospitals, critical power for health care facilities (i.e., primary, vision, and dental care) located in these strip malls can help ensure only the most critical health problems are seen at hospitals. On-site power generation at local schools can serve as convergence points for first responders or for displaced people in a community. For schools, independently powering the office, computer lab, kitchen, and gymnasium, which take about a third of the overall energy, can make the facility usable in the worst situations. When the times are good, they contribute to significant reductions in utility costs.
Considering the importance of water for human sustenance–most humans perish without water in three to four days–it is crucial for all these critical convergence points to have water reserves for people to access. These reserves can be treated and reused on site with backup filtration solutions, many of which are available off the shelf and can function even without an on-site energy supply.
In the Caribbean, rainwater harvesting can capitalize on the amount of precipitation during rainy months to curb demand during dry periods, while granting communities and individuals localized access to clean water even during disasters. Making better use of available water resources, such as rainwater, not only improves access to clean water but also reduces the need for energy-intensive and waste-producing extraction and treatment processes such as desalination. Recycling wastewater for uses that do not require drinking-quality water, such as irrigation and toilet flushing, can further alleviate water demands. Stormwater management tools, such as bioswales, green roofs, rain gardens, and retention ponds, can improve water quality and mitigate flood risks. They offer additional benefits to communities as well, including the creation of outdoor spaces that people can enjoy for various recreational purposes. These measures, coupled with water-efficient fixtures inside buildings, can dramatically reduce the demand for fresh water or groundwater. Establishing community-based water treatment and supply systems can also help decrease the amount of water loss during conveyance due to leakage, which wastes 46 billion liters of drinking-quality water a day globally.
The approaches discussed here not only help prevent and mitigate the consequences of disasters, but can also provide benefits year-round. Decrease in public energy demands on the central electrical grid improves energy efficiency, which is more cost-effective and reduces distribution line congestion. In island communities such as the Caribbean, this significantly improves the resilience of the electric grid itself during unforeseen events, which can include disasters and other unexpected changes in supply and demand. Resilient energy infrastructure in turn increases the resilience of the public water, sewage, and communications infrastructure. Along similar lines, improving reliable water access through the efficient use of existing water resources reduces the substantial energy demands required for treatment and conveyance. Further, it allows even remote communities to have access to clean water at all times, including during and after disasters when lack of clean water and sanitation can result in the spread of waterborne diseases and other public health threats.
For electricity, rather than focusing on one technology, the entire portfolio of renewable energy and advanced hybrid distributed generation needs to be deployed in modular, standardized systems that are interoperable with web-enabled diagnostics. Instead of re-connecting lots of wires, electricity can be delivered through segmented, self-healing grids, similar to those that cellular communications and the internet have adopted. Grid planning and critical infrastructure seem to be evolving on autopilot. Now is the time to re-think and re-orient our options in a more practical and resilient profile where grids are segmented and each segment is composed of several microgrids, which blend and manage on-site generation, energy storage and electric load reduction seamlessly. In buildings, solar water heating, solar daylighting, and geothermal heat pumps can produce energy on-site reliably and cost-effectively, and additional high-value energy efficiency measures can dramatically reduce electric costs. When a portion of the electric system is harmed, the remaining segments and microgrids can isolate themselves and remain functioning.
For water, it is time to stop the practice of treating the different scales and uses of water as separate and unrelated entities and adopt an integrated management plan that incorporates the entire water system. This means taking a holistic look at drinking water, wastewater, groundwater, surface water, flood control measures, and other factors related to the water system, as they are interrelated and cannot be managed properly in isolation. For example, water extraction methods such as well-drilling, done without considering the larger hydrological network, can affect freshwater availability in lakes, rivers, and other surface waterbodies that are connected. Considering the interrelations before jumping into action can help formulate solutions that tackle multiple issues at once, including water quality and availability, flood risk management, biodiversity, energy, place-making, and community development.
While these proven, cost-effective options are used today throughout the United States and many places around the world, they now need to be optimally integrated into wider regional systems. Practical education for engineers, architects, urban planners, and energy and water systems procurement personnel needs to start now.
Short-term relief and long-term resilience in post-disaster reconstruction address the importance of energy and water independence, especially from extreme weather and other unforeseen risks. There are other long-term considerations specific to the Caribbean, and a major one is tourism. The Caribbean’s natural assets–the pristine beaches and mountains, and the plentiful sunshine–continue to draw many visitors and to play a key role in sustaining island economies. Balancing the resource demands of the visitors and the need to maintain these natural assets, which help attract the visitors in the first place, has been a challenge in the past. While tourists and residents do not share the same stake in resource use, there is a strong and growing interest among tourists in eco-tourism. In addition to increasing resilience, a decentralized and distributed energy and water infrastructure based on locally available resources and clean technology can be an opportunity for island communities not only to conserve their resources and to reduce their operating costs and pollution, but also to signal their leadership in sustainable tourism. As a result, short-term relief activities can present opportunities to enhance the hospitality industry for growth and resilience, by playing a larger role in disaster planning, which can dramatically reduce their operating costs while ensuring the preservation of natural assets for the attraction of visitors for years to come.
The technologies to make this happen exist and are economical in an extremely wide-range of applications. They are not being utilized and integrated due to a lack of general knowledge of system integration and modern procurement guidelines, as well as a lack of practical regional and land use planning tools and generalized and specific education. Localities need to amp up training and education at a variety of levels so that governmental, financial, and corporate decision-makers can ask the right questions, and be open to embracing next generation technologies to drive resilient growth that is right for individual communities.
Scott Sklar has run The Stella Group, Ltd for 17 years, which is a clean technology optimization firm, after 15 years running both the solar and biomass industry associations in Washington, DC. He was Political Director of the Solar Lobby for 2 years, after 3 years at the Nat’l Center for Appropriate Technology as both the RD&D and Washington Director. Scott served for 9 years as an energy/military aide to Senator Jacob K Javits (NY). He lives in a zero-energy solar home and has a zero-energy office building – both in Arlington, Virginia. Sklar serves as Steering Committee Chair of the Sustainable Energy Coalition, and sits on the national Boards of Directors of The Solar Foundation and the Business Council for Sustainable Energy. Sklar is an Adjunct Professor at GWU teaching two unique interdisciplinary courses on sustainable energy, and an Affiliated Professor at CATIE, a sustainable graduate university based in Costa Rica. In 2014, Sklar received The Charles Greeley Abbot Award by ASES and the Green Patriot Award by GMU, and serves as Vice Chair of the US Department of Commerce Renewable Energy and Energy Efficiency Advisory Committee through 2018.
Hyon K. Rah, LEED AP, ENV SP, is a resilience planner who designs and implements multi-benefit water and energy management strategies that address multiple risks at once while meeting local communities’ needs. An architect, a water resource manager, and a dot-connector, she has worked in over 30 countries, supporting clients facilitate, plan, and implement community and hospitality development projects in five languages – English, Korean, Japanese, German, and Spanish. Rah instills in future professionals the interrelationship between the built environment and the social, economic, and environmental contexts as an Adjunct Professor at the University of the District of Columbia (UDC), and serves on Metropolitan Washington Council of Governments (MW COG)’ Air and Climate Public Advisory Committee. She is Principal of RAH Solutions, a DC-based consultancy that provides community-based and integrated water and energy solutions for sustainable development.