Discussing current issues in engineering
Wind accounts for the highest percentage of renewable energy generation in the United States. According to the U.S. Energy Information Administration, 8.4% of all electricity produced in the U.S. is derived from wind energy. In 2020, wind accounted for 43% of renewables-based electricity generation—5% more than hydropower and more than ten times the combined electricity yields of biomass, solar, and geothermal energy.
Electricity-generating wind turbines have occupied scattered spaces in the U.S. electricity landscape since their initial conception in the late nineteenth century. When oil shortages in the 1970s forced a reevaluation of the nation’s energy environment, federally funded research and development brought wind turbines into the mainstream.
Despite more than a century of use, the design of electricity-generating wind turbines has remained relatively unchanged. Now, Spain-based tech startup Vortex Bladeless is refreshing the traditional means of wind energy generation with a wind machine that forgoes the defining characteristics of a turbine.
Vortex’s wind machine is a modular, on-site wind energy generator without blades or rotating parts. The machine is comprised of a cylindrical body surrounding a central support that is anchored to the ground. Its ability to generate energy relies on a principle of fluid dynamics called called vortex shedding.
Vortex shedding occurs when fluids (like water or air) flow past a blunt body, creating alternating vortices at the back of the body that detach to form a “vortex street.” When wind passes through the blunt body, the cylinder oscillates toward the alternating low-pressure vortices and subsequently triggers a coil-and-magnet alternator system attached to the central support. Through this process, wind energy becomes mechanical energy becomes electrical energy. In action, the vortex machine resembles one prong of a struck tuning fork rather than the pinwheel shape of a turbine.
Vortex Bladeless launched initial manufacturing with a first series of Vortex Nano devices measuring in at 85 centimeters tall. The company has plans to manufacture generators in a variety of sizes in order to meet site-specific needs. Next on the list is the Vortex Tacoma: a 2.75-meter-tall generator weighing less than 15 kilograms with the capacity to generate 100w. Product features like variable sizing, a light weight, and a low center of gravity hold promise for the wind machine’s ability to occupy a variety of settings, whether rural hilltops or skyscraper railings.
Click here to read more about electricity generation in the United States. For more on the Vortex Bladeless wind machine, click here.
The Navajo Nation retains the largest land area of any indigenous tribe in the United States. Navajo land spans 27,000 square miles—an area larger than West Virginia—and occupies territory in three states: Arizona, Utah, and New Mexico. More than 173,000 of the 298,000 enrolled Navajo members live on Navajo Nation soil.
According to the Indian Health Service (IHS) and the Navajo Tribal Utility Authority, an estimated twenty to thirty percent of the Nation’s residents do not have access to piped water in their homes. Most occupants of homes without piped water rely on hauled water. In some cases, occupants may rely on bottled water for drinking, cooking, cleaning, and bathing.
The COVID-19 pandemic, which has rocked the Navajo Nation with 30,350 cases to date, exacerbated preexisting strains placed on Navajo communities through insufficient and unreliable water access. To combat these deficits, advocates from a variety of sectors—Navajo Nation and federal officials, nonprofits, universities, utility providers—united to form the Navajo Nation COVID-19 Water Access Coordination Group (WACG) which aims to increase tribal homes’ access to safe, quality drinking water.
Last year, in an effort to further WACG's mission, the Indian Health Service and Navajo Engineering & Construction Authority (with the help of Federal CARES Act funds) installed small hydrants connected to piped water throughout the Navajo Nation, creating 58 new transitional water points available to tribal households. This more than doubled the 48 existing water access points in the Navajo Nation. Furthermore, for the duration of the Navajo Nation COVID-19 Public Health Emergency, CARES Act funds enable the WACG to waive water fees and provide water storage containers and disinfection tablets free of charge.
Funding has equipped the WACG to expand water access in the Navajo Nation during the COVID-19 pandemic, but health, human services, and Native justice advocates continue to search for economically feasible infrastructure expansion solutions that will last beyond the current health crisis. As facilities on tribal lands near the end of their life expectancy, more systems need maintenance and replacement, resulting in high estimated construction costs passed on to consumers who may not be able to afford higher utility costs. Rex Kontz, deputy general manager of the Navajo Tribal Utility, says that when it comes to raising utility rates, “all you’ll get is a bunch of people disconnected for nonpayment.”
While there is still an effort to supply homes with piped water, long term solutions to Navajo water inaccessibility may look different from solutions found in many parts of the United States. Navajo officials and utility providers are considering large water loading stations with high flow rates that could serve more residents than the new water access points. WACG members, including the IHS and Johns Hopkins University, are also assessing tech-based solutions like hydropanels and solar powered filters at wellheads.
For more on the Navajo Nation Water Access Coordination Group, click here. To read more about water access points installed in the Navajo Nation, click here.
President Biden’s recent unveiling of the $2 trillion American Jobs Plan renews emphasis on improvements to underperforming infrastructure. As the U.S. enters warmer months, wildfires and wildfire prevention will resume a chief position among infrastructure concerns.
2020 was the worst wildfire season experienced by America’s western states in 70 years. Thousands of Americans evacuated their homes throughout the season, and residents in and around wildfire-stricken areas endured air quality that ranked among the worst in the world.
Last week, the American Society of Civil Engineers (ASCE) hosted an ASCE Interchange interview with Geoff Coleman, a wildfire resilience expert and the vice president of California-based engineering firm BKF Engineers. Coleman spoke with Interchange’s Casey Dinges on key considerations for the future of wildfire-resilient infrastructure in America.
Coleman stressed the importance of public education on wildfire risks and mitigation strategies in fire-prone areas. He recommended that individuals consider evacuation routes and defensible space—the area around a structure designed to reduce fire danger—in home planning and maintenance, and suggested alternatives to traditional grass yards like rock gardens and drought-resistant, high moisture succulents.
More significantly, Coleman stressed the role that civil engineers and appointed officials must play in limiting community fire risks. When fires take hold of a wildland area, entire communication systems, water supplies, electric grids, and transportation networks are threatened. Coordination among emergency responders can be interrupted through the destruction of remotely located communication towers. Burning plastics and industrial materials may contaminate water that is then drawn back into municipal water supplies. An inability to isolate electric services can lead to mass shutdowns.
In order to diminish these possibilities, engineers and community leaders can focus on increasing defensible space around essential structures like water towers, cell towers, and power stations. Better yet, these essential structures can be located outside of fire-prone areas. Roads should be designed with evacuation, response, and reconstruction in mind: paved with compliant turnarounds, multiple points of egress, and widths in excess of forty feet to enable transportation of sufficient water supplies during a fire event and construction equipment in the aftermath.
Lastly, Coleman stressed the importance of introducing fire safety and prevention early into the design process through the involvement of fire code officials. The combined vigilance of engineers and their communities is required to create infrastructure that prioritizes public safety in wildfire-prone areas.
To view ASCE Interchange’s interview with Geoff Coleman, click here.
Colman Engineering, PLC
A professional engineering firm located in Harrisonburg, VA