Warming up to a New Look at Solar Energy

by Robert Rampani

Photo by Roy Bury. [CC0 1.0]

Flipping on a light switch. Charging a cell phone. Driving to Starbucks. For most of us, especially in the routine-filled world of virtual learning, our everyday actions with power consumption are barely an afterthought. There seem to be so many more pressing issues than a potential energy crisis – after all, is that not for the smartest minds of our generation to worry about? Such apathy towards the world’s tremendous consumption of energy is one of the many reasons the production and use of fossil fuels are so rampant across many parts of the globe. While the ramifications of such use go without saying, continued use of fossil fuels and the limits of those resources has created, albeit gradually, one of the greatest problems science has to face in the twenty-first century. Dr. Gerald Meyer, a Professor of Chemistry at UNCChapel Hill, remembers sitting with his father in a long, tedious line for gasoline during the OPEC oil crisis of the 1970s when the apathy of the reliance on petroleum was turned on its head. Dr. Gerald Meyer, PhD. The strong dependence on the limited supply of fossil fuels, especially gasoline, was increasingly apparent during the peak days of the scare. From that moment forward, Dr. Meyer has dedicated much of his life’s work to discovering novel, renewable ways to meet the energy requirements of the world through his research in inorganic chemistry. According to Dr. Meyer, the limited supply of fos-

Figure 1. Hubbert’s Peak, showing peak oil production during the 2020s. Image courtesy of WikiCommons.

sil fuels should not be news to anyone – including large energy-producing corporations.2 In the 1950s, M. King Hubbert, a groundbreaking geologist who worked for the Shell Oil Company, developed what is now known

as Hubbert’s Peak: an approximation of oil production on a worldwide scale (Figure 1).2 While the approximation has not always been accurate, its data does represent a hard truth. Hubbert’s peak predicts that, while petroleum reserves will last longer than many activists suggest, they will eventually decline until wells dry up.2 Therefore, the next 100-200 years of remaining supply give researchers, including a new research partnership headed by Dr. Meyer, vital time to discover and employ innovative research methods to develop new renewable energy technology. While growing in public favor and implementation, current renewable technology is far from dominating the energy marketplace. Figure 2. CHASE Scientists: A Collaborative Effort Many avenues exist, including hydroelectric dams, gen- vides large amounts of energy in a compact and highly erating power from the tides and ocean currents, digging efficient way, but manipulating molecules and attemptgeothermal wells, and the vast breadth of wind power, ing to understand the complex reactions of the quantum especially across the flat Midwest and coastlines of the world can be hard to grasp and even harder to control. United States. Still, none come close in possible energy The basic principles of chemical reactions are being production to meet the world’s needs other than solar pushed to their limits to react CO2, notoriously stable and energy. A simple walk outside during the hot months of pesky to use, to bond carbon atoms to each other. The the Carolina summer makes it clear that the problem is carbons could build up to common molecules used for not a lack of abundance of solar energy striking the Earth; energy production such as ethanol, butanol, and – in an the problem is the storage of the power.1 The question ideal world – other molecules that make up gasoline and of storage is where Dr. Meyer’s passion for research and natural gas. 1 development in renewable energy comes in. Dr. Meyer hopes he, along with 30 scientists from The newly formed Center for Hybrid Approaches in the various institutions enrolled in the program across the Solar Energy to Liquid Fuels, or CHASE, is an exciting, col- country (Figure 2), can make significant breakthroughs laborative effort between UNC-CH, North Carolina State over the next few years. Those goals include demonstratUniversity, Yale University, the University of Pennsylvania, ing that once-theoretical concepts are possible, which Emory University, and the United States Department of has caught the attention of the United States DepartEnergy’s Brookhaven National Laboratory on Long Island. ment of Energy and has secured $40 million in funding Their goal, while complex and beyond the scope of many for CHASE. undergraduate chemistry classes, is to use the power of Dr. Meyer implores students and faculty of UNC to the sun to create liquid fuels to store solar energy in a investigate the data and come to their own conclusions more efficient way than traditional battery technology. about greenhouse gas emission and climate change. He Chemical bonds can “store” solar energy through urges those of the next generation to take a hard look transferring that radiation into Gibbs free energy, which at the world’s situation and strive for the eventual domican be transformed through various chemical reactions. nance of renewable energy. “These huge problems will By the principles of thermodynamics, everything wants be solved one person at a time through slow and steady to be at the lowest energy state, including atoms that research,” he admitted. It will require each of us to make bond together to form molecules. When creating a bond, incremental advancements that impact the world for the atoms lower their individual energies and – through re- better.1 The task is now ours, and it is up to us to ensure actions completed later on with that molecule – that en- the Earth is available, in all its beauty and splendor, for ergy in the bond can be expressed in a variety of ways. generations to come.CHASE hopes to use simple and abundant molecules, like CO2 and H2O, to achieve its goals. References The concepts of energy storage may sound simple 1.Interview with Gerald Meyer, Ph.D. 09/08/20. enough, but CHASE and Dr. Meyer are heading quickly 2.Hubbert, M. King; Shell Development Company into uncharted territory. “Storage” in chemical bonds pro- Exploration and Production Division 1956, 59

A “Turtle-y” New View By Maya Groff

Almost every month, thousands of olive ridley sea turtles flood the shores of Ostional, Costa Rica, covering the soft, cool sand with their olive colored shells. The turtles travel from all stretches of the ocean and swarm onto the shore for a nesting event called the arribada. Despite the arribada’s grandeur, olive ridley sea turtles, and five other participating species, are listed on the International Union for Conservation of Nature Red List of Threatened Species, primarily as a result of human behavior. This categorization indicates that the sea turtles will become endangered without adequate protection measures. The gravity of many species’ situation highlights the importance of collecting sea turtle population data in order to ensure their survival. With the development of aerial imaging, scientists have recently enlisted unmanned aerial vehicles, or drones, in their efforts to track sea turtles. However, the images captured by drones require tedious analysis in order to determine the number of turtles in each shot. UNC Chapel Hill Professor of Biology Kenneth Lohmann hopes to apply machine-learning technology to expedite this analysis process. His team

Dr. Kenneth Lohmann

utilizes a technique known as convolutional neural networks to analyze photographs taken by drones flown above the ocean during mass sea turtle nesting events. To develop this technique, Dr. Lohmann and his team conducted

Olive ridley sea turtle quantified using machine learning technology.

Photo by C Watts [CC-BY-2.0]

Figure 1. Drone image showing the presence of olive ridley sea turtles. Image courtesty of Dr. Lohmann twenty drone imaging flights. Then, they utilized a selection of the resulting data to train the convolutional neural network. During this training process, a series drone images were uploaded to the network and the team “taught” it to determine which displayed turtles, and which did not. Another set of images could then be analyzed using the trained convolutional neural network to count the number of olive ridley sea turtles present during the arribada. However, the fact that sea turtles are in constant motion poses a significant challenge. As Dr. Lohmann says, “there are complications because you

catch the turtles in different positions – as they’re swimming, they move their flippers down, or you can catch the turtles with their flippers tucked in close.” 1 Therefore, the convolutional neural network must be trained to recognize that a single turtle may exist in a range of different orientations. To address this issue, convolutional neural networks were trained using image samples of turtles in a variety of positions, allowing the technology to account for the movement of each turtle and determine their presence at a specific moment. Despite this challenge, Dr. Lohmann’s study found that convoFigure 3. Drone used to collect aerial images of olive ridley sea turtles. Image courtesy of Dr. Lohmann lutional neural networks represent your machine vision system would killing of many turtles during higha successful method for analyzing automatically analyze all of those for density nesting periods. Therefore, drone imagery of olive ridley sea tur- you,” allowing for immediate detec- regularly scanning for sea turtle dentles. He comments, “It was very excit- tion of animal density in an area. 1 sity near the Costa Rican coast could ing to see that these problems can be The greater significance of Dr. assist locals in the enforcement of overcome — we can create technol- Lohmann’s study lies in the poten- protective measures and the limitaogy with a good counting system in tial for such technology to be imple- tion of harmful activities during periwhich the numbers look pretty simi- mented for the protection of a wide ods of time in which large gatherings lar to what we get if we painstakingly of turtles are present. Similar shifts in go through and count the turtles in “The greater significance human behavior would have a huge the images.” 1 The use of convolutional neural networks drastically reduces of Dr. Lohmann’s study impact on the protection of this spe cies. the time and brainpower required to lies in the potential for The development of machine analyze aerial photographs of marine wildlife; it also improves counting such technology to be learning technology capable of processing images has the potential to accuracy. Machine learning technol- implemented for the be of tremendous benefit to not only ogy positively identified 8-9% more turtles than human analysis, demon- protection of a wide range olive ridley sea turtles, but also to other at-risk wildlife in all environments strating a more accurate and reliable of endangered species.” around the world. Machine learning determination of sea turtle density. 2 lends us a heightened awareness of In regard to future develop- species density and position, which ment of image processing technol- range of endangered species. The allows for the protection of some of ogy, Dr. Lohmann says, “the dream ability to quickly and easily collect the world’s most vulnerable inhabitversion is to send your drone out over wildlife population data allows for the ants. However, the responsibility does the water to collect the video, and identification and limitation of harm- not fall solely on technological adful human actions in order vancements like the methods develto protect those species. oped by Dr. Lohmann’s team. It is up Most behavior that nega- to the rest of the world to implement tively impacts olive ridley his research alongside a commitment sea turtles occurs along to protect endangered species. the shore, including intentional capture of turtles References for their skin and meat 1. Interview with Kenneth Lohmann, as well as accidental en- PhD. 9/18/20 snarement of turtles dur- 2. Gray, P; Fleishman, A; Klein, D; Figure 2. Arribada, mass nesting event of olive ridley sea turtles. Photo by Wikimedia Commons. ing fishing. Shrimp fishing, for example, often results McKown, M; Bézy, V; Lohmann, K; Johnston, D. Methods Ecol and Evol. in inadvertent capture and 2018, 10, 345-355.