ARPA-E Awardee Spotlights
In this season of thanksgiving, ARPA-E is highlighting several awardees who are changing our nation’s energy landscape and challenging the status quo by developing entirely new ways to generate, store, and use energy. These two ARPA-E projects, highlighted below, have the potential to radically improve U.S. economic prosperity, national security, and environmental well-being. We’re thankful that these projects are creating long-term impacts in the energy space:
Smart Wires PowerLine GuardianTM
Smart Wires, formerly known as Smart Wire Grid, developed a solution for controlling power flow within the electric grid. Their product named the PowerLine GuardianTM is a device that clamps on to existing transmission line conductors and allows the operator to increase the line impedance on command using wireless communication control. The self-powered controller acts like a valve on the power line; it is capable of redirecting power to underutilized power lines in a meshed network for greater efficiency and overload prevention.
Smart Wires’ power flow control devices are an early success story in demonstrating the potential to increase overall grid transmission capacity use by improving the utilization of existing lines. Field testing and validation of the Smart Wires devices is on-going, and will provide industry context not only for the Smart Wires approach, but also will allow field tests of power flow control as an operational approach.
The final impact on the transmission system will depend on widespread acceptance and adoption of power flow control as a viable planning and operational approach, but the expected benefits include reduced need for expensive new transmission infrastructure, improved grid reliability and resiliency, reduced congestion and ability to integrate higher penetrations of renewable power sources.
Stanford Radiative Cooling
Over the past 50 years, the growing use of air conditioning has resulted in a significant increase in the usage of electricity and water. In the U.S. today, the electricity required to cool residential and commercial buildings accounts for 6 and 8% of total electricity production, respectively. Additionally, standard air conditioners transfer heat from inside to outside a building, exacerbating external heating that can contribute to the urban ‘heat island’ effect, where the outside ambient temperature is higher than surrounding rural areas. Technological innovations in cooling systems are needed to improve energy and water use in buildings, and reduce CO2 and other harmful emissions associated with cooling.
The project team from Stanford University further explored these issues and has since invented a novel coating material that can help cool buildings, even on sunny days, by radiating heat away from the buildings and sending it directly into space. The key to Stanford’s cooling approach is to employ a multilayered coating to reflect nearly all the sunlight across the solar spectrum and also emit energy in the mid infrared frequency range between 8 and 13 micrometers– employing a “window” in the atmosphere that allows a thermal connection to deep space. In this way, waste heat is removed from the local environment.
The Stanford University project team has demonstrated its technology in tests during full solar illumination on a California rooftop and shown that it could lower temperatures between 3 to 5°C. Moreover, the demonstration of this novel, passive cooling technology developed by the Stanford University team has led several separately funded groups to propose similar approaches to passive, radiative cooling as part of ARPA-E’s new program on Advanced Research In Dry-Cooling (ARID). The ARID program addresses the efficiency of thermoelectric power plants where water use for cooling is restricted. Radiative cooling is a promising approach to create a cold-storage reservoir to chill recirculated cooling water.