Combining Energy Efficiency and Disaster Mitigation Efforts in Residential Properties

Combining Energy Efficiency and Disaster Mitigation Efforts in Residential Properties

Highlights

• In many cases, materials and technologies that enhance a building’s energy efficiency can also make the building more durable and resilient to threats posed by natural disasters.
• Interventions such as the use of cogeneration systems and microgrids can help communities better withstand and recover from natural disasters that threaten their electricity supply.
• Increasing public awareness directly influences the adoption and implementation of energy-efficient and resilient design in postdisaster rebuilding.

Natural disasters are devastating to communities and homes, yet they can also offer an opportunity to integrate energy-efficient and disaster-resilient technologies and materials during the reconstruction process. Understanding how stakeholders make decisions following a disaster can help us learn how to encourage collaboration and eliminate potential barriers to integrating efficiency and mitigation efforts. Although these efforts may incur additional costs or slow construction or rebuilding, high-performance buildings generate significant long-term savings in energy costs, increase the structures’ durability, and reduce the waste produced from damaged or destroyed buildings.

At a 2014 U.S. Department of Energy seminar on disaster recovery, nearly 70 percent of participants indicated that the “lack of a clear response plan or protocol” and the “lack of awareness about energy efficiency” were the biggest barriers to coordinating energy efficiency and disaster recovery in their communities.1 Research, however, tells us that engaging experts in combining these efforts can yield tremendous value, providing long-term benefits to single-family homeowners and communities and contributing to the broader goal of creating strong, sustainable cities.

Combining Energy Efficiency and Disaster Resilience

U.S. families spend, on average, $114 each month on their electric bill.2 Advanced energy-efficient technologies and practices improve home energy performance by making homes more comfortable and increasing their long-term durability. Optimizing energy efficiency when building a new home or extensively remodeling an existing home requires a whole-house systems approach. A whole-system approach to energy efficiency considers all the variables, details, and interactions that affect energy in homes, including appliances and home electronics; insulation and air sealing; lighting and daylighting; space heating and cooling; water heating; and windows, doors, and skylights.

Policies and programs from federal, state, and local governments can reduce energy consumption and help homeowners save money on their energy bills. Energy rebate programs and financing options encourage homeowners to implement energy-efficient technologies and help reduce the cost of making energy efficiency improvements in new or existing homes.

In terms of disaster risk and mitigation, RealtyTrac, a real estate research firm, found that 43 percent of U.S. homes and condominiums — a total of 35.8 million homes — are at a high or very high risk of at least one type of natural disaster, such as a wildfire, hurricane, flood, tornado, or earthquake.3 Natural disasters threaten to displace families from residential properties, but resilient housing can accommodate the stresses of a severe weather event. Resilience refers to “the ability to prepare and plan for, absorb, recover from, and more successfully adapt to adverse events.”4 Put another way, resilience is “the ability not only to bounce back [after a disaster] but also to ‘bounce forward’ — to recover and at the same time to enhance the capacities of the community or organization to better withstand future stresses.”5 Characteristics of resilient homes include the ability to absorb shocks, the use of light-colored materials in sections that are prone to hot temperatures, and the flexibility to expand and adapt when needed. Resilient homes are part of an extensive support system to create and maintain resilient people and communities.6

The initial period after a natural disaster serves as a ripe opportunity for communities to use recovery and rebuilding to enhance resiliency. Many resiliency measures in the built environment overlap with energy-efficiency measures that can further benefit the community through lower operating costs and energy savings that reduce stress on energy infrastructure. Homeowners, architects, and builders can find ways to incorporate energy-efficient elements into their designs while achieving performance goals, including resistance to natural hazards. Sustainable design and construction constitute a cornerstone for developing resilient communities.

A lack of collaboration between those interested in increasing energy efficiency and those seeking improved disaster resilience is a potential source of inefficiency because both groups strive to improve the performance of the same buildings. Developers, homeowners, and community stakeholders involved in new building and renovation efforts do not always have the same goals. Developers are typically profit driven, whereas community stakeholders or homeowners may be more interested in building long-term, durable residential properties. Making communities disaster resilient with high-performance technologies often increases build time and material costs.7

Energy efficiency and disaster management share some benefits and challenges, and integrating these two within public policy and programs would benefit society. Following a natural disaster, however, state and local governments and residents face many decisionmaking challenges that complicate the integration of energy efficiency and resiliency into residential rebuilding. These challenges include “motivating property owners and developers to value energy efficiency and disaster resilience during the rebuilding process; identifying and understanding the various sources of federal, state, and private rebuilding funding and assistance; and working with property insurance providers to allow upgrades of rebuilt homes above the value of the pre-existing structure.”8

Strategies for Effective Disaster Mitigation and Rebuilding Efforts

A lack of awareness is one of the most significant factors limiting the integration of energy efficiency and resilience. Campaigns to increase public awareness should focus on three areas: the value of residential energy efficiency and resilience; available state, utility, and federal programs; and energy-efficient and resilient design and building technologies. Increasing public awareness directly influences the adoption and implementation of energy-efficient and resilient design in post-disaster rebuilding.

Disaster rebuilding coordination is most effective when relationships are in place before a disaster and all stakeholders share the same vision. In an analysis of U.S. public policies addressing energy efficiency and disaster management, Martel finds, “energy efficiency and disaster management have some complementary policies, actors, interest groups, regulatory systems, goals, and desired outcomes… [but] these two fields have not comprehensively converged, missing opportunities for greater positive impact on society.”9 Connecting stakeholders (including state and federal emergency management agencies), utility providers, contractors and homebuilders, financial institutions, public housing agencies and home associations, and large retailers and hardware stores ensures that stakeholders are working toward the same shared vision.10

Certain building technologies advance the goals of both helping homes become more resilient to natural disasters and improving the energy performance of the building. Innovations in resource-efficient and durable residential design and construction have become a reality in several places, from model housing developments in tornado-prone Greensburg, Kansas, to rebuilding efforts in Long Island, New York, following Superstorm Sandy. These strategies include incorporating onsite renewable energy sources to reduce environmental impacts and reliance on the electrical grid as well as elevating buildings and moving mechanical systems to the roof to make buildings more flood resistant.

Disaster-resistant and energy-efficient homes have common structural benefits, such as greater construction durability and performance. Recent technology advancements have helped homeowners more easily invest in elements that make their homes more resilient to natural disasters while also improving their energy efficiency.11

Extreme Heat and Cold. Vulnerable populations, such as children, the elderly, and the economically disadvantaged are at heightened risk of death and illness during periods of extreme heat or cold.12 Building technologies can help prepare residential homes for the potential impacts of extreme heating and cooling events while protecting the health, safety, and welfare of residents.13 Homes with effective air sealing and high insulation have an energy-efficient building envelope that reduces heating and cooling loads. Residential buildings with smaller load demands not only decrease the strain on regional electrical grids during emergencies such as natural disasters but also are more likely to keep occupants safe and minimize the negative effects of extreme heat or cold.14

In regions at risk of extreme cold, water pipes are more likely to freeze, and moisture flow due to air leakage and vapor diffusion from the inside to the outside can cause discomfort. Insulation is an energy-efficient solution that protects residents and buildings from extreme cold. Insulated walls reduce the risk of frozen water lines, keep homes warmer, reduce energy costs, and maintain comfortable indoor temperatures. Elements such as double-paned windows also improve a home’s response to extreme cold while reducing energy consumption.15

Land modifications and building materials that absorb the sun’s heat, especially in urban or metropolitan areas, can raise surrounding air temperatures in a phenomenon known as the urban heat island effect. Design elements for the roof are among the most common and cost-effective solutions to reducing the effects of extreme heat while reducing energy consumption. A garden planted on a rooftop, known as a green roof, reduces the roof’s surface temperature. Similarly, a “cool roof” that reflects sunlight and heat lowers the surface temperature. (See “Green Infrastructure: Revisiting Natural Systems Technology To Meet Present and Future Resilience Needs.”) Strategies such as green and cool roofs lower indoor temperatures, increase occupant comfort, and reduce the amount of air conditioning needed on hot days. 16

A hipped roof, in which the roof slopes on four sides instead of two, with a wide overhang can provide solar shading. To protect against uplift during high-wind events, additional connections are needed to secure the roof to the exterior wall.17

External strategies such as planting trees and vegetation that directly shade homes can also lower surrounding temperatures. Trees provide passive cooling through their shade, reduce the urban heat island effect, and may reduce flooding by slowing down water flow, increasing water absorption into the ground, and preventing soil erosion.18

Seismic Hazard. Earthquakes pose a particular risk for older homes because they often are not adequately anchored to their foundations and were not designed to withstand the shaking and movement typical of an earthquake. Identifying potential hazards in advance allows homeowners to undertake projects that simultaneously target energy efficiency and seismic resilience.

Although building materials and technologies tend to focus on either energy efficiency or seismic resilience, opportunities exist to combine the two elements. Some wood-framed homes use weak bracing materials such as cement plaster or wood siding, which are not strong enough to survive moderate to strong earthquakes, leak heated or cooled air, and risk the home’s longevity. Replacing the bracing materials with plywood or concrete can help reduce the home’s energy consumption and increase its structural strength.19

Wind Hazard. High wind events such as tornadoes, hurricanes, windstorms, and severe winter storms can affect homes in two ways. First, differential pressures act on the building envelope, which includes the roof and walls. Excessive differential pressures caused by wind can deform or dislodge building materials. For example, roof shingles and siding can be broken or lifted off. Second, windborne debris may strike the home.

Expanding the use of certain materials can be a more cost-effective way for new and existing homes to be more resilient and energy efficient. Multipane windows, for example, reduce the risk of breakage during a high-wind event and reduce energy consumption during heating and cooling. Concrete homes and structurally insulated walls both conserve energy used for heating and cooling and are resistant to falling or flying debris.

Crews work to restore electricity in New Jersey following Superstorm Sandy, which caused outages for more than 8.5 million customers. FEMA Photo by Sharon Karr

Flood Hazard. Typically, builders increase residential resilience to flooding through improvements to building codes rather than by using innovative technologies and building materials. But common strategies, such as elevating homes, do not capture energy savings. Researchers, however, are testing new flood-resilient construction materials that are also sustainable. Researchers at the University of Bath are testing the flood resilience and structural integrity of timber walls, which may be used to floodproof future homes.20

Community-Based Technologies

Community-based strategies for improving energy efficiency and flood resilience can also be effective. In Hackbridge, United Kingdom, solar panels, biomass, and heat pumps — renewable energy sources that can operate during a flood — will power new buildings located in the city’s flood zone. Other cities such as Hoboken, New Jersey; New York City; and Washington, DC, are implementing microgrids to improve resilience to coastal flooding.21

Technologies such as cogeneration systems and smart meters are also examples of opportunities that combine resiliency with energy efficiency at the community level. These technologies are most effective when they work concurrently toward achieving those goals.

Cogeneration Systems. Cogeneration, also known as combined heat and power (CHP), refers to multiple technologies that operate concurrently to generate electricity and heat. When incorporated widely within a community, the community can be self-sufficient even if it becomes disconnected from the central utility and can better meet surges in power demand associated with extreme weather or natural disasters.22

South Oaks Hospital in Amityville, New York, for example, used a natural gas-fired CHP system to operate and serve patients despite being disconnected from the Long Island Power Authority grid for 15 days.23

Microgrids. From 2003 to 2012, the United States experienced more than 675 widespread power outages due to extreme weather, costing the U.S. economy an average of $18 billion to $33 billion annually. 24 Major natural disasters result in widespread power outages, leaving thousands without access to heating, cooling, and hot water. Both seismic events and floods associated with tsunamis and hurricanes can damage electricity transmission and distribution systems, and can impede the delivery of fuel to local generators. Other natural disasters, such as ice storms and wildfires, can also affect the delivery of electricity.25

Increased grid resilience in the form of microgrids may help communities maintain power during natural disasters because a microgrid is a localized grid that is able to disconnect and isolate itself from the utility.26 Although microgrids are often seen as a way to encourage the adoption of renewable energy sources and address the challenges of peak demand, they can also contribute significantly to a community’s disaster preparedness and recovery. By relying on multiple generators, a microgrid system avoids the single point of failure of traditional electricity grids. Microgrids may disconnect from the grid during power outages to allow facilities receiving backup power to double as shelter for displaced residents; they can also reduce energy overconsumption and expenses.27

In September 2015, the Butte Fire in California’s Calaveras County burned more than 545 homes and charred nearly 71,000 acres, destroying power lines in its path.28 Although many homes lost power as firefighters battled to control the flames, the lights stayed on at the Miwuk Tribe’s Jackson Rancheria Casino and Hotel Resort. Jackson Rancheria used its microgrid to disconnect from the regional power grid and generate its own electricity. In a time of crisis, Jackson Rancheria served as a haven for firefighters and a temporary home for hundreds of evacuees. After seeing the success at Jackson Rancheria, other Tribes in high-risk wildfire areas are also planning to implement microgrids. Plans for a microgrid at Blue Lake Rancheria estimated savings of at least $75,000 per year in energy expenses.29

Smart Meters. Smart meters, electronic devices that record electricity consumption in intervals of an hour or less, aid both energy efficiency and disaster resilience. During natural disasters, smart meters provide power companies with crucial information on the location of power outages, reducing both emergency response times and the duration of outages.

In October 2012, Superstorm Sandy made landfall on the east coast, damaging more than 650,000 homes and causing power outages for 8.5 million customers. The greatest damage occurred in New York and New Jersey, but smart grid investments in Pennsylvania and Washington, DC, reduced the storm’s impact for thousands of electric customers. With funding from a Smart Grid Investment Grant from the U.S. Department of Energy, Philadelphia implemented roughly 186,000 smart meters before Superstorm Sandy hit. PECO, formerly called the Philadelphia Electric Company, estimates that approximately 50,000 of its customers experienced shorter outages during the storm because of its new smart grid system. Advanced smart meter infrastructure in Washington, DC, allowed the Potomac Electric Power Company to quickly pinpoint outage locations, enabling the utility to respond to customers quickly and effectively.30

Future Research Needs

Energy efficiency is an essential component of any resilience strategy because it aids emergency response and recovery, helps with disaster mitigation, and provides social and economic benefits. In addition, there is strategic value in coupling energy efficiency and hazard mitigation features in homes. These high-performance buildings result in:

• Greater occupant comfort and safety;
• Increased durability of properties, resulting in energy savings over time and reduced waste from damaged or destroyed buildings; and
• Reduced operating costs and increased cost savings for homeowners through lower energy bills and insurance premiums.

Although some concerted research efforts link energy efficiency and disaster resilience, Oluwateniola E. Ladipo notes several remaining gaps in these efforts. In general, stakeholders lack consensus on how to define resilience in the residential building sector and how best to evaluate the performance of resilience-enhancing technologies and strategies for residences, which makes comparing and prioritizing these technologies and communicating outcomes difficult. Because this is a new field, stakeholders are encouraged to further explore and examine design and installation techniques.31

Most resilience research in response to natural disasters has been focused on seismic history at the expense of other natural hazards, such as extreme heat and cold or high winds. As a result, efforts to protect buildings against earthquakes have made the most progress. Future research should focus on making buildings more resilient to these and other natural hazards while also integrating energy-efficient technologies. In addition, research has focused on infrastructure and large commercial buildings, such as hospitals, rather than residences, overlooking the significant economic and social impact of incorporating energy efficiency and disaster resilience technologies into homes.32

Finally, research is limited on the proposed methodologies and decisionmaking processes. Future research should address best practices or provide a framework for stakeholders to use when considering and prioritizing technologies for rebuilding after natural disasters.33

— Caitlin Phillips, Former HUD Intern

Related Information:

Green Infrastructure: Revisiting Natural Systems Technology To Meet Present and Future Resilience Needs
Passivhaus in Austria
Rebuilding in Greensburg, Kansas

1. U.S. Department of Energy. 2014. “Better Buildings Residential Network Program Sustainability Peer Exchange Call Series: Incorporating Energy Efficiency into Disaster Recovery Efforts.”
2. U.S. Energy Information Administration. “2015 Average Monthly Bill: Residential” (www.eia.gov/electricity/sales_revenue_price/pdf/table5_a.pdf). Accessed 13 May 2017.
3. Katy Hill. 2015. “43% of U.S. homes are at high risk of natural disaster,” Marketwatch, 3 September.
4. Committee on Increasing National Resilience to Hazards and Disasters and Committee on Science, Engineering, and Public Policy. 2012. Disaster Resilience: A National Imperative, Washington, DC: National Academies Press, 2.
5. Urban Land Institute. 2013. “After Sandy: Advancing Strategies for Long-Term Resilience and Adaptability,” Urban Land Institute, 7.
6. John McIlwain, Molly Simpson, and Sara Hammerschmidt. 2014. “Housing in America: Integrating Housing, Health, and Resilience in a Changing Environment,” Urban Land Institute, 6.
7. Committee on Increasing National Resilience to Hazards and Disasters, Committee on Science, Engineering, and Public Policy, Policy and Global Affairs.
8. National Association of State Energy Officials. 2015. “Resiliency through Energy Efficiency: Disaster Mitigation and Residential Rebuilding Strategies for and by State Energy Offices,” 6–7.
9. J.C. Martel. 2015. “Exploring the Integration of Energy Efficiency and Disaster Management in Public Policies and Programs,” Energy Efficiency 9:2, 533.
10. National Association of State Energy Officials.
11. Martel, 534.
12. U.S. Environmental Protection Agency and Centers for Disease Control and Prevention. 2016. “Climate Change and Extreme Heat: What You Can Do to Prepare,” 8.
13. Martel, 534.
14. National Association of State Energy Officials.
15. David S. Gromala, Omar Kapur, Vladimir Kochkin, Philip Line, Samantha Passman, Adam Reeder, and Wayne Trusty. 2010. “Natural Hazards and Sustainability for Residential Buildings,” Federal Emergency Management Agency.
16. U.S. Environmental Protection Agency and Centers for Disease Control and Prevention, 16.
17. Gromala et al., 4–6.
18. Sustainable Green Initiative. “How trees help in preventing floods” (www.greening.in/2013/05/how-trees-help-in-preventing-floods.html). Accessed 22 May 2017.
19. City of Portland, Bureau of Development Services. 2016. “Residential Seismic Strengthening: Methods to Reduce Potential Earthquake Damage,” 2–3.
20. University of Bath. 2014. “New sustainable, flood-resilient construction materials put to the test,” press release, 25 September.
21. Jean-Marie Cariolet, Marc Vuillet, Morgane Colombert, and Youssef Diab. 2016. “Building resilient and sustainable: a need to decompartementalise the researches,” E3S Web Conferences, 7, 13012.
22. Oluwateniola Ladipo. 2016. “Making Communities Disaster Resilient with High-Performance Building Technologies,” dissertation, Virginia Polytechnic Institute and State University, 2–3.
23. Anne Hampson, Tom Bourgeois, Gavin Dillingham, and Isaac Panzarella. 2013. “Combined Heat and Power: Enabling Resilient Energy Infrastructure for Critical Facilities,” ICF International, 13.
24. President’s Council of Economic Advisers and U.S. Department of Energy, Office of Electricity and Energy Reliability. 2013. “Economic Benefits of Increasing Electric Grid Resilience to Weather Outages,” 3.
25. International Electrotechnical Commission. 2014. “Microgrids for disaster preparedness and recovery,” 17.
26. Lawrence Berkeley National Laboratory. “Microgrids at Berkeley Lab: About Microgrids” (building-microgrid.lbl.gov/about-microgrids). Accessed 13 May 2017.
27. President’s Council of Economic Advisers and U.S. Department of Energy, Office of Electricity and Energy Reliability, 14–5.
28. California Department of Forestry and Fire Protection. “Incident Information: Butte Fire” (cdfdata.fire.ca.gov/incidents/incidents_details_info?incident_id=1221). Accessed 22 May 2017.
29. Edward Ortiz. 2015. “Microgrids Sustain Power During Natural Disasters,” Sacramento Bee, 20 October.
30. President’s Council of Economic Advisers and U.S. Department of Energy, Office of Electricity and Energy Reliability, 10.
31. Ladipo, 35.
32. Ibid.
33. Ibid.