Beginning 2020, the fifth generation of wireless technology is expected to be widely implemented throughout the world. The new network, called 5G, promises to give faster speeds and a higher capacity for the use of more devices. However, while companies from countries such as the United States and China are competing to be the first to deliver 5G to the consumer, the environmental impacts of the new network are being overlooked. In a time when the environment is at its most delicate, overlooking these impacts is extremely risky for future generations.
The main environmental issues associated with the implementation of the 5G network come with the manufacturing of the many component parts of the 5G infrastructure. In addition, the proliferation of new devices that will use the 5G network that is tied to the acceleration of demand from consumers for new 5G-dependent devices will have serious environmental consequences.
The 5G network will inevitably cause a large increase in energy usage among consumers, which is already one of the main contributors to climate change. Additionally, the manufacturing and maintenance of the new technologies associated with 5G creates waste and uses important resources that have detrimental consequences for the environment. 5G networks use technology that has harmful effects on birds, which in turn has cascading effects through entire ecosystems. And, while 5G developers are seeking to create a network that has fewer environmental impacts than past networks, there is still room for improvement and the consequences of 5G should be considered before it is widely rolled out.
What is 5G?
5G stands for the fifth generation of wireless technology. It is the wave of wireless technology surpassing the 4G network that is used now. Previous generations brought the first cell phones (1G), text messaging (2G), online capabilities (3G), and faster speed (4G). The fifth generation aims to increase the speed of data movement, be more responsive, and allow for greater connectivity of devices simultaneously. This means that 5G will allow for nearly instantaneous downloading of data that, with the current network, would take hours. For example, downloading a movie using 5G would take mere seconds. These new improvements will allow for self-driving cars, massive expansion of Internet of Things (IoT) device use, and acceleration of new technological advancements used in everyday activities by a much wider range of people.
While 5G is not fully developed, it is expected to consist of at least five new technologies that allow it to perform much more complicated tasks at faster speeds. The new technologies 5G will use are hardware that works with much higher frequencies (millimeter wavelengths), small cells, massive MIMO (multiple input multiple output), beamforming, and full duplex. Working together, these new technologies will expand the potential of many of the devices used today and devices being developed for the future.
Millimeter waves are a higher frequency wavelength than the radio wavelength generally used in wireless transmission today. The use of this portion of the spectrum corresponds to higher frequency and shorter wavelengths, in this case in the millimeter range (vs the lower radio frequencies where the wavelengths can be in the meters to hundreds of kilometers). Higher frequency waves allow for more devices to be connected to the same network at the same time, because there is more space available compared to the radio waves that are used today. The use of this portion of the spectrum has much longer wavelengths than of that anticipated for a portion of the 5G implementation. The waves in use now can measure up to tens of centimeters, while the new 5G waves would be no greater than ten millimeters. The millimeter waves will create more transmission space for the ever-expanding number of people and devices crowding the current networks. The millimeter waves will create more space for devices to be used by consumers, which will increase energy usage, subsequently leading to increased global warming.
Millimeter waves are very weak in their ability to connect two devices, which is why 5G needs something called “small cells” to give full, uninterrupted coverage. Small cells are essentially miniature cell towers that would be placed 250 meters apart throughout cities and other areas needing coverage. The small cells are necessary as emissions [or signals] at this higher frequency/shorter wavelength have more difficulty passing through solid objects and are even easily intercepted by rain. The small cells could be placed on anything from trees to street lights to the sides of businesses and homes to maximize connection and limit “dead zones” (areas where connections are lost).
The next new piece of technology necessary for 5G is massive MIMO, which stands for multiple input multiple output. The MIMO describes the capacity of 5G’s base stations, because those base stations would be able to handle a much higher amount of data at any one moment of time. Currently, 4G base stations have around eight transmitters and four receivers which direct the flow of data between devices. 5G will exceed this capacity with the use of massive MIMO that can handle 22 times more ports. Figure 1 shows how a massive MIMO tower would be able to direct a higher number of connections at once. However, massive MIMO causes signals to be crossed more easily. Crossed signals cause an interruption in the transmission of data from one device to the next due to a clashing of the wavelengths as they travel to their respective destinations. To overcome the cross signals problem, beamforming is needed.
Figure 1. 5G Network of Base Towers, Small Cells, and Stylized Disruptions
To maximize the efficiency of sending data another new technology called beamforming will be used in 5G. For data to be sent to the correct user, a way of directing the wavelengths without interference is necessary. This is done through a technique called beamforming. Beamforming directs where exactly data are being sent by using a variety of antennas to organize signals based on certain characteristics, such as the magnitude of the signal. By directly sending signals to where they need to go, beamforming decreases the chances that a signal is dropped due to the interference of a physical object.
One way that 5G will follow through on its promise of faster data transmission is through sending and receiving data simultaneously. The method that allows for simultaneous input and output of data is called full duplexing. While full duplex capabilities allow for faster transmission of data, there is an issue of signal interference, because of echoes. Full duplexing will cut transmission times in half, because it allows for a response to occur as soon as an input is delivered, eliminating the turnaround time that is seen in transmission today.
Because these technologies are new and untested, it is hard to say how they will impact our environment. This raises another issue: there are impacts that can be anticipated and predicted, but there are also unanticipated impacts because much of the new technologies are untested. Nevertheless, it is possible to anticipate some of detrimental environmental consequences of the new technologies and the 5G network, because we know these technologies will increase exposure to harmful radiation, increase mining of rare minerals, increase waste, and increase energy usage. The main 5G environmental concerns have to do with two of the five new components: the millimeter waves and the small cells.
Increased Energy Usage of the 5G Network
The whole aim of the new 5G network is to allow for more devices to be used by the consumer at faster rates than ever before, because of this goal there will certainly be an increase in energy usage globally. Energy usage is one of the main contributors to climate change today and an increase in energy usage would cause climate change to increase drastically as well. 5G will operate on a higher frequency portion of the spectrum to open new space for more devices. The smaller size of the millimeter waves compared to radio frequency waves allows for more data to be shared more quickly and creates a wide bandwidth that can support much larger tasks. While the idea of more space for devices to be used is great for consumers, this will lead to a spike in energy usage for two reasons – the technology itself is energy demanding and will increase demand for more electronic devices. The ability for more devices to be used on the same network creates more incentive for consumers to buy electronics and use them more often. This will have a harmful impact on the environment through increased energy use.
Climate change has several underlying contributors; however, energy usage is gaining attention in its severity with regards to perpetuating climate change. Before 5G has even been released, about 2% of the world’s greenhouse gas emissions can be attributed to the ICT industry. While 2% may not seem like a very large portion, it translates to around 860 million tons of greenhouse gas emissions. Greenhouse gas emissions are the main contributors to natural disasters, such as flooding and drought, which are increasing severity and occurrence every year. Currently, roughly 85% of the energy used in the United States can be attributed to fossil fuel consumption. The dwindling availability of fossil fuels and the environmental burden of releasing these fossil fuels into our atmosphere signal an immediate need to shift to other energy sources. Without a shift to other forms of energy production and the addition of technology allowed by the implementation of 5G, the strain on our environment will rise and the damage may never be repaired. With an increase in energy usage through technology and the implementation of 5G, it can be expected that the climate change issues faced today will only increase.
The overall contribution of carbon dioxide emissions from the ICT industry has a huge impact on climate change and will continue to have even larger impacts without proper actions. In a European Union report, researchers estimated that in order to keep the increase in global temperature below 2° Celsius a decrease in carbon emissions of around 15-30% is necessary by 2020.
Engineers claim that the small cells used to provide the 5G connection will be energy efficient and powered in a sustainable way; however the maintenance and production of these cells is more of an issue. Supporters of the 5G network advocate that the small cells will use solar or wind energy to stay sustainable and green. These devices, labeled “fuel-cell energy servers” will work as clean energy-based generators for the small cells. While implementing base stations that use sustainable energy to function would be a step in the right direction in environmental conservation, it is not the solution to the main issue caused by 5G, which is the impact that the massive amount of new devices in the hands of consumers will have on the amount of energy required to power these devices.
Consumption Increases and 5G Technologies
The wasteful nature of manufacturing and maintenance of both individual devices and the devices used to deliver 5G connection could become a major contributor of climate change. The promise of 5G technology is to expand the number of devices functioning might be the most troubling aspect of the new technology. Cell phones, computers, and other everyday devices are manufactured in a way that puts stress on the environment. A report by the EPA estimated that in 2010, 25% of the world’s greenhouse gas emissions comes from electricity and heat production making it the largest single source of emissions. The main gas emitted by this sector is carbon dioxide, due to the burning of natural gas, such as coal, to fuel electricity sources. Carbon dioxide is one of the most common greenhouse gases seen in our atmosphere, it traps heat in earth’s atmosphere trying to escape into space, which causes the atmosphere to warm generating climate change.
Increased consumption of devices is taking a toll on the environment. As consumers gain access to more technologies the cycle of consumption only expands. As new devices are developed, the older devices are thrown out even if they are still functional. Often, big companies will purposefully change their products in ways that make certain partner devices (such as chargers or earphones) unusable–creating demand for new products. Economic incentives mean that companies will continue these practices in spite of the environmental impacts.
One of the main issues with the 5G network and the resulting increase in consumption of technological devices is that the production required for these devices is not sustainable. In the case of making new devices, whether they be new smart-phones or the small cells needed for 5G, the use of nonrenewable metals is required. It is extremely difficult to use metals for manufacturing sustainably, because metals are not a renewable resource. Metals used in the manufacturing of the smart devices frequently used today often cannot be recycled in the same way many household items can be recycled. Because these technologies cannot be recycled, they create tons of waste when they are created and tons of waste when they are thrown away.
There are around six billion mobile devices in use today, with this number expected to increase drastically as the global population increases and new devices enter the market. One estimate of the life-time carbon emissions of a single device–not including related accessories and network connection–is that a device produces a total of 45kg of carbon dioxide at a medium level of usage over three years. This amount of emission is comparable to that of driving the average European car for 300km.
But, the most environmentally taxing stage of a mobile device life cycle is during the production stage, where around 68% of total carbon emissions is produced, equating to 30kg of carbon dioxide. To put this into perspective, an iPhone X weighs approximately 0.174kg, so in order to produce the actual device, 172 iPhone X’s worth of carbon dioxide is also created. These emissions vary from person to person and between different devices, but it’s possible to estimate the impact one device has on the environment. 5G grants the capacity for more devices to be used, significantly increase the existing carbon footprint of smart devices today.
Energy usage for the ever-growing number of devices on the market and in homes is another environmental threat that would be greatly increased by the new capabilities brought by the 5G network. Often, energy forecasts overlook the amount of energy that will be consumed by new technologies, which leads to a skewed understanding of the actual amount of energy expected to be used. One example of this is with IoT devices. IoT is one of the main aspects of 5G people in the technology field are most excited about. 5G will allow for a larger expansion of IoT into the everyday household. While some IoT devices promise lower energy usage abilities, the 50 billion new IoT devices expected to be produced and used by consumers will surpass the energy used by today’s electronics.
The small cells required for the 5G network to properly function causes another issue of waste with the new network. Because of the weak nature of the millimeter waves used in the 5G technology, small cells will need to be placed around 250 meters apart to insure continuous connection. The main issue with these small cells is that the manufacturing and maintenance of these cells will create a lot of waste. The manufacturing of technology takes a large toll on the environment, due to the consumption of non-renewable resources to produce devices, and technology ending up in landfills. Implementing these small cells into large cities where they must be placed at such a high density will have a drastic impact on technology waste.
Technology is constantly changing and improving, which is one of the huge reasons it has such high economic value. But, when a technological advancement in small cells happens, the current small cells would have to be replaced. The short lifespan of devices created today makes waste predictable and inevitable. In New York City, where there would have to be at least 3,135,200 small cells, the waste created in just one city when a new advancement in small cells is implemented would have overwhelming consequences on the environment. 5G is just one of many examples of how important it is to look at the consequences of new advancements before their implementation. While it is exciting to see new technology that promises to improve everyday life, the consequences of additional waste and energy usage must be considered to preserve a sustainable environment in the future.
The Impact of 5G on Ecosystems
There is some evidence that the new devices and technologies associated with 5G will be harmful to delicate ecosystems. The main component of the 5G network that will affect the earth’s ecosystems is the millimeter waves. The millimeter waves that are being used in developing the 5G network have never been used at such scale before. This makes it especially difficult to know how they will impact the environment and certain ecosystems. However, studies have found that there are some harms caused by these new technologies.
The millimeter waves, specifically, have been linked to many disturbances in the ecosystems of birds. In a study by the Centre for Environment and Vocational Studies of Punjab University, researchers observed that after exposure to radiation from a cell tower for just 5-30 minutes, the eggs of sparrows were disfigured. The disfiguration of birds exposed for such a short amount of time to these frequencies is significant considering that the new 5G network will have a much higher density of base stations (small cells) throughout areas needing connection. The potential dangers of having so many small cells all over areas where birds live could cause whole populations of birds to have mutations that threaten their population’s survival. Additionally, a study done in Spain showed breeding, nesting, and roosting was negatively affected by microwave radiation emitted by a cell tower. Again, the issue of the increase in the amount of connection conductors in the form of small cells to provide connection with the 5G network is seen to be harmful to species that live around humans.
Additionally, Warnke found that cellular devices had a detrimental impact on bees. In this study, beehives exposed for just ten minutes to 900MHz waves fell victim to colony collapse disorder. Colony collapse disorder is when many of the bees living in the hive abandon the hive leaving the queen, the eggs, and a few worker bees. The worker bees exposed to this radiation also had worsened navigational skills, causing them to stop returning to their original hive after about ten days. Bees are an incredibly important part of the earth’s ecosystem. Around one-third of the food produced today is dependent on bees for pollination, making bees are a vital part of the agricultural system. Bees not only provide pollination for the plant-based food we eat, but they are also important to maintaining the food livestock eats. Without bees, a vast majority of the food eaten today would be lost or at the very least highly limited. Climate change has already caused a large decline in the world’s bee population.
The impact that the cell towers have on birds and bees is important to understand, because all ecosystems of the earth are interconnected. If one component of an ecosystem is disrupted the whole system will be affected. The disturbances of birds with the cell towers of today would only increase, because with 5G a larger number of small cell radio-tower-like devices would be necessary to ensure high quality connection for users. Having a larger number of high concentrations of these millimeter waves in the form of small cells would cause a wider exposure to bees and birds, and possibly other species that are equally important to our environment.
The Importance of a Proactive Approach
As innovation continues, it is important that big mobile companies around the world consider the impact 5G will have on the environment before pushing to have it widely implemented. The companies pushing for the expansion of 5G may stand to make short term economic gains. While the new network will undoubtedly benefit consumers greatly, looking at 5G’s long-term environmental impacts is also very important so that the risks are clearly understood and articulated.
The technology needed to power the new 5G network will inevitably change how mobile devices are used as well as their capabilities. This technological advancement will also change the way technology and the environment interact. The change from using radio waves to using millimeter waves and the new use of small cells in 5G will allow more devices to be used and manufactured, more energy to be used, and have detrimental consequences for important ecosystems.
While it is unrealistic to call for 5G to not become the new network norm, companies, governments, and consumers should be proactive and understand the impact that this new technology will have on the environment. 5G developers should carry out Environmental Impact Assessments that fully estimate the impact that the new technology will have on the environment before rushing to widely implement it. Environmental Impact Assessments are intended to assess the impact new technologies have on the environment, while also maximizing potential benefits to the environment. This process mitigates, prevents, and identifies environmental harm, which is imperative to ensuring that the environment is sustainable and sound in the future.
Additionally, the method of Life Cycle Assessments (LCA) of devices would also be extremely beneficial for understanding the impact that 5G will inevitably have on the environment. An LCA can be used to assess the impact that devices have on carbon emissions throughout their life span, from the manufacturing of the device to the energy required to power the device and ultimately the waste created when the device is discarded into a landfill or other disposal system. By having full awareness of the impact new technology will have on the environment ways to combat the negative impacts can be developed and implemented effectively.
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 Figure taken from Al-Falahy, NFA and Alani, OYK. Potential technologies to 5G network: challenges and opportunities. 2017.
 Sitch, Will. MIMO and Beamforming in the 5G Context: SBrT 2017. Keysight Technologies. 2017.
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 Wang, Li-Chun & Rangapillai, Suresh. A Survey on Green 5G Cellular Networks. National Chiao Tung University. 2012.
 National Academy of Sciences, National Academy of Engineering, and National Research Council. 2009. America’s Energy Future: Technology and Transformation. Washington, DC: The National Academies Press.
 Garg, Saurabh Kumar & Yeo, Chee Shin & Buyya1, Rajkumar. Green Cloud Framework for Improving Carbon Efficiency for Clouds. Department of Computer Science and Software Engineering at The University of Melbourne, Australia. Springer, Berlin, Heidelberg. 2011.
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 Ibid, p1.
 Ibid, p4.
 Patterson, Steven Max. 4 reasons Cisco’s IoT forecast is right, and 2 why it’s wrong. Network World. April 5, 2017.
 Cisco Mobile VNI. Cisco Visual Networking Index: Global Mobile Data Traffic Forecast Update, 2017-2022 White Paper. Updated: February 18, 2019.
 Nordrum, Clark, & IEEE Spectrum Staff, 2017.
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 Warnke, Ulrich. Birds, Bees and Humankind: Destroying Nature by ’Electrosmog’. Competence Initiative for the Protection of Humanity, Environment and Democracy. March 2009.
 Sivani & Sudarsanam, 2013, p206.
 Ibid, p207.
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