The Coming 5G Revolution: How Will It Affect the Environment?
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Photo: Can Pac Swire
COVID-19 has made one thing crystal clear: Society needs the Internet to function. During the pandemic, the Internet has been critical for buying groceries, working, educating children, getting medical care, accessing news and being entertained. The health and safety of the population depends on the reliability of the network. Since January, the daily broadband use of individual Americans has increased 3 gigabytes —enough capacity to browse the Internet for 90 hours or watch HD movies for an hour. All this demand for fast, reliable and diversified communication has increased pressure on countries to quickly adopt 5G—the latest generation of digital technology.
The promise of 5G
Approximately every ten years, new wireless mobile technology emerges that improves on the previous generation. 1G, which came out in the 1980s, supported only voice calls. 2G, born in the 1990s as cell phones went from analog to digital, enabled messaging and call and text encryption to keep communications secure.
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1G on the left, 3G on the right. Photo: Charles Wiriawan
In 1998, 3G made video calling and mobile Internet access possible. 4G, introduced in 2008, supports HD TV via mobile, video conferencing and gaming. Today most cell phones use 3G and 4G technology.
5G, which began deployment in 2019, can deliver enhanced broadband for cell phones, super fast and reliable communication, and machine-to-machine communication. It promises to be 100 times faster than 4G. But beyond speed and connectivity, 5G also has ultra low latency—latency is any delay in communications—and 1,000 times more capacity because it is expanding into new frequencies of the spectrum. This will eventually make wireless Internet possible everywhere, from smart cars to the Internet of Things (IoT), which can connect all kinds of devices and sensors through the Internet and allow them to communicate without human involvement.
How does 5G work?
The spectrum
To understand what 5G is, it’s important to first understand the spectrum. The electromagnetic spectrum is the range of all types of electromagnetic radiation. The radio spectrum is the part of the spectrum used for telecommunication, broadcast, aircraft communication and more, and ranges from 30 hertz (Hz) to 300 gigahertz (1 GHz is equal to 1 billion hertz). The overall spectrum also includes visible light, gamma rays, x-rays, microwaves, etc. Spectrum on the lower end, called low-band (600 million hertz (MHz) to 900 MHz) has longer waves and can travel farther. As waves range from mid-band (2.5GHz to 4.2GHz) to high-band—also known as millimeter wave (24GHz to 47GHz)—they get shorter and shorter, enabling more bandwidth (the amount of data that can be transmitted in a specific amount of time) but losing the ability to travel as far.
While low-band can penetrate walls well, its speed is limited to 100 megabytes per second (Mbps). Mid-band spectrum speed can reach 1 billion bytes or 1 gigabyte per second (Gbps); it has lower latency than low-band, but it cannot go through buildings as easily. High-band or millimeter wave (mmWave) has very low latency and is super fast, up to 10 Gbps. These high frequency mmWaves also offer increased transmission space so more devices can be connected at once. The drawback is that they are weaker and cannot easily penetrate solids. 5G operates on all three spectrum bands.
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The US radio spectrum. Photo: US Dept. of Commerce
Government agencies in every country control the spectrum and designate who can use which frequencies. In the United States, the Federal Communications Commission (FCC) controls the spectrum and separates it into different chunks, which are then assigned or sold to companies and industries. In 2016, the FCC opened up large amounts of high-band spectrum for 5G.
Infrastructure and data transmission
Because mmWaves can travel only a short distance, small cell towers, about the size of a medium suitcase, will need to be placed 250 meters apart, such as on rooftops, telephone poles, trees, and street lights to ensure comprehensive coverage in cities.
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5G cellular antennas on a Pittsburgh rooftop
Photo: Tony Webster
Unlike tall 4G cell towers that transmit longer frequency waves over longer distances, the small cell base stations, containing the equipment that transmits data to and from devices, need a direct line of sight to the devices with which they communicate.
The base stations house a large number of antennae, which increases the capacity of the network. These antennae use “beamforming” to coordinate the numerous transmissions, prevent them from interfering with each other, and send focused data to the specific individual user. This enables the small cell to handle many different data streams at the same time. The small cells are connected to the 5G network and Internet usually via fiber optic cable or wireless microwave. They also need a power source. A typical small cell may require 200 to 1,000 watts of power.
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5G base stations. Photo: Nenad Stojkovic
To enable the network to respond to all types of demands, “network slicing” creates self-contained networks or slices that meet different needs and requirements. For example, one network slice could require only low -security and low bandwidth while another needs high security and high reliability.
Satellites
Satellites can provide 5G coverage where it is difficult to build enough cell towers, as well as take over critical functions if a natural disaster or terrorist attack knocks out the communication infrastructure on land. Recently, SpaceX, Elon Musk’s company, launched 595 small satellites (with an ultimate goal of 30,000) that orbit in low Earth orbit (LEO), 500 to 2,000 kilometers above Earth. The FCC has approved other LEO satellite systems including Amazon’s Kuiper System of 3,236 satellites; and a number of systems have been approved by other countries as well. The constellations of LEO satellites will hand off transmission between the individual satellites to provide extensive coverage in the air, at sea and in remote areas. But larger satellites that already operate in orbits farther from Earth can also handle 5G transmission. The various satellite systems differ in their coverage, power requirements, latency and economic viability.
How can 5G help the environment?
The speed, capacity and connectivity of 5G will provide many opportunities to protect and preserve the environment. 5G technology with IoT will be able to increase energy efficiency, reduce greenhouse gas emissions and enable more use of renewable energy. It can help reduce air and water pollution, minimize water and food waste, and protect wildlife. It can also expand our understanding of and hence improve decision-making about weather, agriculture, pests, industry, waste reduction and much more.
According to the UN, 68 percent of the world’s population will live in cities by 2050. City governments and businesses are looking to 5G, artificial intelligence (AI) and IoT technology to create smart cities where sensors, cameras and smart phones will be linked; the connectivity and speed of these networks will enable cities to be better managed and more efficient and sustainable.
Here are just some of the ways, 5G can benefit the environment.
Reducing energy consumption and emissions
International standards have called for 5G to require much less energy to run than 4G, which means using less power while transmitting more data. For example, one kilowatt-hour (kWh) of electricity is needed to download 300 high-definition movies in 4G; with 5G, one kWh can download 5,000 ultra-high-definition movies.
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The Internet of Things. Photo: Wilgengebroed
5G linked with IoT will also cut energy use, because devices will be able to power up and shut down automatically when not needed. Sensors in appliances, transportation networks, buildings, factories, street lights, residences and more will monitor and analyze their energy needs and consumption in real time and automatically optimize energy use. For example, smart electricity meters installed in the Empire State Building have helped cut energy costs by 38 percent. GE’s Digital Power Plant for Steam in France, equipped with 10,000 sensors to improve plant efficiency, got the Guinness World Record for the world’s most efficient power plant.
Because saving energy also means cutting greenhouse gas emissions, GE’s Digital Power Plant software is expected to reduce carbon emissions by 3 percent and fuel use by 67,000 tons of coal per year. A study done by Ericcson, a leading information and communication technology provider, projects that IoT could cut carbon emissions 15 percent by 2030.
5G and the IoT will enable microgrids to be brought on line when the main grid fails or is unavailable. This will make it possible to better integrate intermittent renewable energy sources such as wind and solar into the grid. Ameresco, a Massachusetts-based company, replaced an old steam plant with a fully automated plant supported by 20,000 solar modules and its own microgrid at the U.S. Marine Corps Recruit Depot on Parris Island, S.C. The system reduced energy use by 75 percent.
By enabling more people to work or access entertainment remotely and avoid commuting and flying for business, 5G will save energy and reduce greenhouse gas emissions from vehicles and airplanes.
If driving is a necessity, 5G can save time, fuel and vehicle emissions by reducing traffic congestion and idling. With sensors and cameras, 5G uses real time data to keep traffic flowing, changing traffic lights to avoid delay. Carnegie Mellon’s Metro21: Smart Cities Institute’s smart traffic control system, which employs radar and cameras to reduce idling, has resulted in 20 percent fewer greenhouse gas emissions in Pittsburgh. 5G can also reduce the number of cars on the road by helping drivers find parking spaces and enabling ride sharing.
Reducing water and food waste
According to the EPA, U.S. households waste one trillion gallons each year due to leaks. Smart water sensors can detect leaks, as well as water pollution and contamination.
Sensors can also optimize agricultural water use. Arable, an innovative agricultural company, uses smart agricultural sensors that incorporate weather information and soil and crop conditions to better manage irrigation and make it more efficient. The systems also monitor plant stress, nutrients and pests to help plan harvests.
The UN has estimated that about one-third of the food produced globally is wasted, which also wastes the energy and water that went into it. Agricultural sensors can detect when a plant is wilting, so they can help ensure that crops are harvested at the right time. Other sensors can detect food freshness and spoilage, so that consumers know when food is safe to eat without depending on expiration dates. 5G could eventually be used to tag all food where it’s produced, track harvest dates or identify specific animals, and then trace the smart tags as food is transported to the factory. Other sensor systems could monitor conditions in the factory, assessing the food for quality and compliance with regulations. An automated and transparent system could make sure that the correct ingredients are delivered at the right time and packaged properly. This would help reduce food waste, maximize food safety, evaluate a food’s sustainability, and allow a supply chain to respond more quickly to supply and demand issues.
Protecting nature
To keep sewage from polluting the St. Joseph River in South Bend, Ind., smart sewer technology was installed in manholes. The technology reduced sewage overflows by 70 percent —over one billion gallons a year—and saved the city more than $500 million.
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Blue-green algae in the Baltic Sea. Photo: European Space Agency
Toxic blue-green algae bloom when water temperatures are warmer than usual. Nokia used 5G drones with cameras and sensors over the Baltic Sea to detect blue-green algae growth in real time. While algae are normally monitored by observation from shore, the drones made it possible to detect algae blooms in more remote areas. Getting timely information enables experts to rapidly take actions to prevent such environmental hazards.
Australian start-up Myriota and the Australian Institute of Marine Science (AIMS) are using marine buoys with satellite-connected IoT sensors to track ocean currents, sea surface water temperatures, and the barometric pressure of the ocean in real time. This helps researchers better monitor changing conditions in the ocean and understand how the ocean behaves.
Rainforest Connection, a nonprofit fighting illegal deforestation, is working with 5G and AI to protect the rainforest in Costa Rica. AI recorders recognize the sounds of chainsaws and other machinery, so they can alert rangers about illegal logging in real time. They can also distinguish the sounds of animals under stress so that rangers can respond quickly to illegal poaching.
The International Union for Conservation of Nature uses 5G geolocation technology to track the location and movements of endangered animals. And at the Chengdu Research Base of Giant Panda Breeding in China, 5G is being used to monitor panda conditions and encourage breeding. Pandas only ovulate once a year and are fertile for only 24 to 36 hours so breeding them is challenging. The technology identifies panda mating calls and plays them back to the pandas to encourage them to mate with each other.
5G’s potentially negative impacts on the environment
Since 5G is a new technology, its long-term effects on the environment are unknown. However, there are already concerns that 5G could have negative effects on the environment because of its energy use, and the impacts of manufacturing new infrastructure and a multitude of new devices.
More energy consumption and emissions
Currently, information and communications technology is responsible for about 4 percent of global electricity consumption, and 1.4 percent of global carbon emissions. But an Ericcson report projects that by the end of 2025, 5G will have 2.6 billion subscribers; total global mobile subscriptions are expected to reach 5.8 billion by then. By 2030, IoT devices around the world could number 125 billion. At that point, information technology is expected to be responsible for one-fifth of all global electricity consumption and by 2040, it could generate 14 percent of worldwide greenhouse gas emissions. If the entire system is not energy efficient, 5G will ultimately not be sustainable.
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Cloud computing data center. Photo: Berkeley Lab
Data storage centers that handle cloud computing and websites, and store our information use enormous amounts of energy—as much as 80 percent of total network energy use. About half of this goes towards keeping transmission equipment in base stations cool. A Berkeley Lab report found that U.S. data centers consumed 70 billion kWh in 2014; this year they are projected to consume 73 billion kWh. Small cell base stations may devour three times as much power as 4G base stations.
Life cycle impacts
In 2019, the president of The Shift Project, a French think tank advocating the shift to a post-carbon economy, said, “…behind each byte we have mining and metal processing, oil extraction and petrochemicals, manufacturing and intermediate transports, public works (to bury the cables) and power generation with coal and gas. As a result, the carbon footprint of the global digital system is already four percent of the global greenhouse gas emissions, and its energy consumption rises by nine percent per year.”
The increase in greenhouse gas emissions will be due in part to the fact that consumers will need to buy new 5G mobile phones in order to take full advantage of 5G. A Swedish study calculated that a smart phone produced 45 kg of CO2 during its entire lifetime, with most of it coming from the production phase—the manufacture of integrated circuits, sourcing the raw material, production of the phone shell, then assembly and distribution. If accessories and the mobile network are included, the total life cycle impact is 68 kg CO2.
The manufacture of more IoT devices and cell phones, and small cells also means more mining and use of many nonrenewable metals that are difficult to recycle.
E-waste
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Photo: Hellebardius
As consumers around the world move to 5G phones, many older phones and IoT devices will be discarded if there are no buy back or recycling plans for them. This will result in enormous amounts of e-waste, which is already a huge global problem.
Radiation
The full deployment of 5G could have a disruptive impact on ecosystems. A Punjab University study found that sparrows exposed to cell tower radiation for five to 30 minutes produced disfigured eggs. In Spain, the nesting, breeding and roosting of birds were disturbed by microwave radiation from a cell tower. Wireless frequencies have also been found to interfere with the navigational systems and circadian rhythms of birds, affecting migration.
Another study found that bees exposed to low-band spectrum radiation for 10 minutes suffered colony collapse disorder. And some research has found that insects, including honeybees, absorb more radiation from the mid-band and 5G spectrum. This could lead to changes in insect behavior and functions over time.
With 5G expected to require the installation of 70.2 million small cell towers by 2025—one survey found that many operators expect to deploy between 100 and 350 small cells per square kilometer (indoors and outdoors)—it is unknown what effect ubiquitous mmWave radiation could have on birds, bees and other species.
Making 5G more sustainable
There are strategies that can and should be employed to lessen the environmental impacts of 5G and make it more sustainable.
Decarbonization
Steve Cohen, director of the Master of Public Administration Program in Environmental Science and Policy at Columbia University’s School of International and Public Affairs, stressed that since 5G will consume a great deal of electricity, decarbonizing our electrical system is critical.
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Microgrids could help decarbonize the grid. Photo: Oak Ridge National Laboratory
This means replacing fossil fuels with renewable energy, improving grid flexibility and storage, and using carbon-capture strategies with any remaining fossil fuel power plants.
More efficient cooling
Some companies are implementing new technologies to reduce the amount of energy networks consume to cool their base stations. In Hangzhou, China, new base stations using intelligent voltage boosting and cooling, and solar modules can save 4,310 KWh of power per site each year, cutting 1,125 kilograms of CO2 emissions. NTT DOCOMO, a Japanese mobile phone company, has developed Green Base Stations with solar photo-voltaic panels and smart power control, reducing commercial power consumption by 40 percent.
Nokia deployed a liquid-cooled base station in Finland; using water to cool the station instead of air consumed 10 percent of the energy of traditional air cooling. With water cooling, it was also possible to use the waste heat from the base stations for water or space heating in the buildings next to the base stations. In addition, data centers cooled with liquid reduced carbon emissions by 90 percent.
Biodegradable sensors
Most of the sensors incorporated into phones, computers and other electronic devices are composed of precious metals that can be harmful to the environment or human health. Some scientists are working on developing biodegradable sensors that dissolve when they are no longer needed. Such sensors could be based on paper or polylactic acid, which are biodegradable, and are already used in medical applications. Researchers at École Polytechnique Fédérale de Lausanne have developed printed humidity and temperature sensors and transistors on biodegradable substances, which could eventually be applied to smart packaging.
Recycling toxic materials
“The biggest danger [about 5G] that I see is the toxics of electronic waste,” said Cohen, “Some of the rare earths and other substances inside of phones can be reused fairly easily and can be mined. The companies that sell them should be required to buy them back at the end—it’s called producer responsibility.” He expects there will be more mining of existing electronic devices by companies that give consumers a discount for trading in their old one, as Apple now does.
Network sharing
Some companies are sharing 5G network infrastructure to potentially cut 30 percent of their costs. McKinsey, the management consulting firm, found that costs to set up small cell base stations could be reduced by half if three players share the network. In China, two companies have agreed to build a 5G network together and share the network infrastructure. Vodafone and Telecom Italia are sharing a network, as are three mobile network operators in South Korea. Beyond cutting costs, network sharing can also reduce environmental impacts by avoiding overlapping dense networks of small cells and reducing the need for equipment and construction in cities.
When will 5G arrive?
The full potential of 5G in cities will be realized only when there is full indoor and outdoor 5G. This will require transmission equipment for IoT to be installed in buildings, on city streets, as well as along transportation routes so that traffic and autonomous vehicles can be managed.
However, because it doesn’t yet make economic sense to build completely new 5G infrastructure, 5G’s rollout will be “evolutionary.” 5G will initially piggyback on the existing 4G network. This entails allowing mobile operators to replace the older equipment in a frequency band with newer equipment. To accommodate 5G, 4G networks will be upgraded to their most advanced versions; some of these advanced 4G cell towers have the capability of being upgraded via software in the future. It is only when both the network infrastructure and the device being used support the same standard that it will be possible for consumers to access all the benefits of 5G; otherwise the service will default to the network that both connections support.
As of June 2020, 5G was available to some degree in 38 countries. In the United States, the three major cell phone carriers (T-Mobile/Sprint, Verizon, AT&T) have deployed some 5G in major cities, and this week, the White House and the Defense Department opened up a new chunk of the spectrum to help speed the 5G rollout. But the extent of 5G service still depends on the availability of more new devices—cell phones and smart sensors. These are expected to be launched late this year and into 2021. The prevailing thinking is that worldwide adoption of 5G is three years away.
Whether or not 5G will be a boon or a bane for the environment remains to be seen. The calculus is complex. “You can’t just look at the technology, use of energy, and use of toxics,” said Cohen. “It’s not a straightforward analysis. I think that, in general, people spending more and more of their time consuming information and entertainment has a lower environmental impact than many of the other things people do, like shopping or driving around. We have to look at this activity compared to what else you’d be doing with your time, and what other environmental impact you’d be having if you weren’t doing this. What would that something else be?”