How 5G Can be Used to Combat Sustainability Challenges

06 December 2021

I wrote this piece for my Telecommunications class (ECE 4450). This research paper discusses how 5G technologies can be used in a sustainable way.

How 5G Can be Used to Combat Sustainability Challenges by Ariana Haghighi

The fifth generation of cellular broadband networks (5G) has become a buzzword in recent years. AT&T, Sprint, and Verizon have started to implement it across the US and heavily advertised 5G-compatible products. What’s the big deal about 5G? Compared to the fourth generation of cellular (4G), 5G promises speeds up to twenty times faster along with many other upgrades. One of 5G’s main distinctions from 4G is its ultra-low latency. This feature is crucial for real-time data analytics like self-driving cars. Where 4G networks could have a minimum of 100 ms of latency, 5G can get as low as 1 ms, which is nearly instantaneous. In terms of bandwidth, current 4G technologies provide a maximum of 200 Mbps, whereas 5G is projected to provide 1 Gbps. Additionally, 5G allows for much denser connections; it can connect ten times more devices in one square-kilometer than 4G. This feature will become incredibly important as more devices are added to the network. Since 5G can handle more devices in a given area, it is much less likely to drop a connection, making it incredibly reliable. While 5G is currently being rolled out in massive urban centers, it will take several years for it to be widely used across the US. In the meantime, researchers have been exploring possible uses for 5G, especially in terms of sustainability. Mitigating the effects of climate change is undeniably one of the most important issues the world is facing. Embedded in the Paris Agreement, 195 countries are working towards a carbon neutral world by 2050 (“Paris”). 5G can be used to help achieve this goal as well as build a more sustainable future in terms of water use, transportation, agricultural practices, and smart grids. That said, many are wary of how 5G will negatively affect efforts to mitigate climate change. Manufacturing new 5G-compatible devices and building 5G cells are not insignificant to the environment (Curran). I will also explore how these concerns about 5G’s carbon footprint will be addressed.

One cannot address sustainability efforts without addressing water consumption. By as soon as 2025, “two-thirds of the world will face water shortages with our current water consumption” according to Phillip Tracy, a writer on water management (West). Clearly, these shortages will cause massive humanitarian and economic crises. However, 5G can be used to reduce and monitor water consumption and mitigate these shortages. According to The American Society for Civil Engineers, there are 240,000 water main breaks per year which accounts for at least one trillion gallons of water being wasted per year (West). These leaks could be quickly detected and fixed with a mesh network of sensors connected to a 5G network. These sensors would monitor the water flow at specific intervals along the water line. They could alert someone when a leak is detected before significant damage is done and large quantities of potable water is wasted. While wireless sensor networks could be used with 4G, they are far better suited for 5G. The key difference is connectivity and real-time updates. Similar sensor networks could be used to monitor leaks within individual homes. Beyond reducing water usage, these sensors could detect water pollution in both drinking water to the home and runoff from manufacturing plants which could harm both people and water life. A key example that could have been avoided is the Flint, Michigan Water Crisis where unsafe drinking water was found in at least 5,000 homes causing severe rashes and in some cases death (West). If simple, inexpensive chemical sensors had been installed and connected via 5G, repairs could have been done before so many people were affected. 5G mesh networks could be used to connect cheap sensors together to reduce water use, fix leaks, and detect water pollution.

Another key difference with 5G is its ability to work in rural areas. Even in 2021, rural areas in the United States have poor 4G cell tower coverage. However, since 5G uses more radio spectrum than other generations of cellular, it would be much easier to increase rural area coverage (Milanesi). Increased rural connectivity allows 5G to have some agricultural use cases including irrigation and pesticide use. Agricultural irrigation is responsible for 80% of water usage in the United States (West). The majority of these irrigation systems are highly inefficient and date back to the twentieth century; they dispense the same amount of water everyday regardless of the weather and current soil moisture levels. Using 5G, a mesh network of cheap sensors could be installed to monitor soil moisture and compile the current weather to determine how much to water crops at a given time on a given day. One company, Arable, has already developed these sensors and they use simple weather metrics like precipitation, temperature, humidity, and the UV index to significantly decrease the amount of water used (Cho). Arable’s sensors also monitor plant stress, soil nutrients, and pests to plan harvest, ultimately reducing the amount of food that is wasted and optimizing farmers’ profits. Another agricultural use case for 5G is pesticide reduction. While more and more farms have stopped using pesticides altogether, the majority of farms use pesticides to increase crop yields. Currently, 5.1 billion pounds of pesticides are used per year. Reducing pesticide usage decreases the cost of food, the amount of runoff into fresh water which affects wildlife, and the amount of pesticides consumed by humans from food. 5G-enabled drones can both reduce pesticide usage and protect farmers from harmful pesticides ("Environmental"). The drones take high resolution pictures of the crops and send them to a computer that assesses how much pesticide needs to be applied and where. The computer relays this information to the drone which then sprays the pesticide. This technique can reduce pesticide usage by 50% ("Environmental"). Beyond reducing the amount of pesticide used, the drones are faster than farmers’ manually applying the spray and the drones can access steeply sloping cultivated areas that are difficult to access from the ground. 5G’s coverage of rural areas has huge implications for farming, making it cheaper, safer, and more sustainable.

Beyond rural use cases, 5G also has many applications in an urban setting, notably transportation. One of 5G’s most-hyped use cases is autonomous vehicles. Its ability to connect so many devices in a small area and its ultra-low latency is perfect for connecting a fleet of self-driving cars in real time. While self-driving cars increase sustainability and safety, we are still quite far away from exclusively having self-driving cars on the streets. However, researchers at Huawei claim that “56% of passenger cars worldwide will have either an embedded or an aftermarket [5G] connection by 2027,” (“Green”). These devices could help manage speed, gear selection, engine idling, and acceleration to reduce the amount of fuel used while driving as well as regularly detect traffic patterns and suggest the best route to reduce emissions ("Environmental," Cho). 30% of transportation-related emissions are created from circling around city blocks looking for parking (West). Sensors detecting open parking spots could be connected to cars using 5G and alert drivers of open spots. This would reduce emissions produced from cars in traffic and improve air quality. Another way to reduce traffic could be improving stop lights. It is estimated that 23% to 45% of urban traffic congestion occurs around traffic intersections (West). Today, traffic lights and stops are highly inefficient since they are static devices. 5G traffic sensors could account for traffic flow rather than changing lights at set intervals, reducing traffic and emissions. Emissions from transportation could be largely reduced in the future with a combination of a fleet of self-driving cars, fully electric vehicles, and a smart grid. The smart grid could efficiently distribute electricity and charge electric vehicles while avoiding power outages (blackouts) and voltage fluctuations (brownouts) (“Environmental”). The fully electric cars would not produce emissions, especially if they are being charged from renewable energy sources. The fleet of self-driving cars would significantly reduce traffic and eliminate the need for stoplights altogether. While this is many years from becoming a reality, 5G could make this possible. Even in the next few years, 5G can reduce traffic and transportation-related emissions with smarter traffic lights, parking-finding tools, and 5G-enabled devices in cars.

While 5G can increase sustainability, many have doubts. Researchers at Columbia think that implementing 5G globally may do more harm than good. They claim: “small cell base stations may devour three times as much power as 4G base stations.” If 5G base stations are powered using fossil fuel (like the majority of 4G stations today), then this would hinder 5G’s sustainability. However, if the base stations are powered using renewable energy, they would significantly decrease emissions. Beyond decarbonizing base stations, they could be more efficiently cool using liquid-based cooling rather than air-based cooling. Nokia experimented with this technique and found it consumed a tenth of the energy (Cho). The researchers also have qualms about e-waste. Every device and much of the infrastructure would need to be updated in order to be compatible with 5G and reap its benefits. For example, everyone would need a new phone. Each phone produces 45kg of CO2 during its lifetime, and the majority of those emissions are produced during the production process rather than when it is being used (Cho). When these devices are not properly recycled, metals and other components are released into the environment which is toxic for wildlife. A possible solution to this problem is a diligent and well-advertised recycling program where metals from old phones are used to manufacture new ones, which would decrease the footprint of new phones while avoiding pollution (Cho). If 5G is implemented with a focus on renewable energy and recycling, then it can help sustainability efforts.

5G promises massive improvements from 4G including faster speeds, ultra-low latency, and greater connectivity. It has a myriad of applications including edge-computing, virtual reality, and remote surgery. However, many of its uses can also be applied to combat sustainability challenges in terms of water waste, agricultural inefficiencies, and vehicle emissions among many other uses. While it may take many years to be fully rolled out, it is undeniably a revolutionary technology. Some question its ability to be sustainable considering the increase in energy usage and need for new devices and infrastructure, however if done correctly, it could still be sustainable.