- ENVIRONMENT
Renewable energy, explained
Solar, wind, hydroelectric, biomass, and geothermal power can provide energy without the planet-warming effects of fossil fuels.
In any discussion about climate change , renewable energy usually tops the list of changes the world can implement to stave off the worst effects of rising temperatures. That's because renewable energy sources such as solar and wind don't emit carbon dioxide and other greenhouse gases that contribute to global warming .
Clean energy has far more to recommend it than just being "green." The growing sector creates jobs , makes electric grids more resilient, expands energy access in developing countries, and helps lower energy bills. All of those factors have contributed to a renewable energy renaissance in recent years, with wind and solar setting new records for electricity generation .
For the past 150 years or so, humans have relied heavily on coal, oil, and other fossil fuels to power everything from light bulbs to cars to factories. Fossil fuels are embedded in nearly everything we do, and as a result, the greenhouse gases released from the burning of those fuels have reached historically high levels .
As greenhouse gases trap heat in the atmosphere that would otherwise escape into space, average temperatures on the surface are rising . Global warming is one symptom of climate change, the term scientists now prefer to describe the complex shifts affecting our planet’s weather and climate systems. Climate change encompasses not only rising average temperatures but also extreme weather events, shifting wildlife populations and habitats, rising seas , and a range of other impacts .
Of course, renewables—like any source of energy—have their own trade-offs and associated debates. One of them centers on the definition of renewable energy. Strictly speaking, renewable energy is just what you might think: perpetually available, or as the U.S. Energy Information Administration puts it, " virtually inexhaustible ." But "renewable" doesn't necessarily mean sustainable, as opponents of corn-based ethanol or large hydropower dams often argue. It also doesn't encompass other low- or zero-emissions resources that have their own advocates, including energy efficiency and nuclear power.
Types of renewable energy sources
Hydropower: For centuries, people have harnessed the energy of river currents, using dams to control water flow. Hydropower is the world's biggest source of renewable energy by far, with China, Brazil, Canada, the U.S., and Russia the leading hydropower producers . While hydropower is theoretically a clean energy source replenished by rain and snow, it also has several drawbacks.
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Large dams can disrupt river ecosystems and surrounding communities , harming wildlife and displacing residents. Hydropower generation is vulnerable to silt buildup, which can compromise capacity and harm equipment. Drought can also cause problems. In the western U.S., carbon dioxide emissions over a 15-year period were 100 megatons higher than they normally would have been, according to a 2018 study , as utilities turned to coal and gas to replace hydropower lost to drought. Even hydropower at full capacity bears its own emissions problems, as decaying organic material in reservoirs releases methane.
Dams aren't the only way to use water for power: Tidal and wave energy projects around the world aim to capture the ocean's natural rhythms. Marine energy projects currently generate an estimated 500 megawatts of power —less than one percent of all renewables—but the potential is far greater. Programs like Scotland’s Saltire Prize have encouraged innovation in this area.
Wind: Harnessing the wind as a source of energy started more than 7,000 years ago . Now, electricity-generating wind turbines are proliferating around the globe, and China, the U.S., and Germany are the leading wind energy producers. From 2001 to 2017 , cumulative wind capacity around the world increased to more than 539,000 megawatts from 23,900 mw—more than 22 fold.
Some people may object to how wind turbines look on the horizon and to how they sound, but wind energy, whose prices are declining , is proving too valuable a resource to deny. While most wind power comes from onshore turbines, offshore projects are appearing too, with the most in the U.K. and Germany. The first U.S. offshore wind farm opened in 2016 in Rhode Island, and other offshore projects are gaining momentum . Another problem with wind turbines is that they’re a danger for birds and bats, killing hundreds of thousands annually , not as many as from glass collisions and other threats like habitat loss and invasive species, but enough that engineers are working on solutions to make them safer for flying wildlife.
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Solar: From home rooftops to utility-scale farms, solar power is reshaping energy markets around the world. In the decade from 2007 and 2017 the world's total installed energy capacity from photovoltaic panels increased a whopping 4,300 percent .
In addition to solar panels, which convert the sun's light to electricity, concentrating solar power (CSP) plants use mirrors to concentrate the sun's heat, deriving thermal energy instead. China, Japan, and the U.S. are leading the solar transformation, but solar still has a long way to go, accounting for around two percent of the total electricity generated in the U.S. in 2017. Solar thermal energy is also being used worldwide for hot water, heating, and cooling.
Biomass: Biomass energy includes biofuels such as ethanol and biodiesel , wood and wood waste, biogas from landfills, and municipal solid waste. Like solar power, biomass is a flexible energy source, able to fuel vehicles, heat buildings, and produce electricity. But biomass can raise thorny issues.
Critics of corn-based ethanol , for example, say it competes with the food market for corn and supports the same harmful agricultural practices that have led to toxic algae blooms and other environmental hazards. Similarly, debates have erupted over whether it's a good idea to ship wood pellets from U.S. forests over to Europe so that it can be burned for electricity. Meanwhile, scientists and companies are working on ways to more efficiently convert corn stover , wastewater sludge , and other biomass sources into energy, aiming to extract value from material that would otherwise go to waste.
Geothermal: Used for thousands of years in some countries for cooking and heating, geothermal energy is derived from the Earth’s internal heat . On a large scale, underground reservoirs of steam and hot water can be tapped through wells that can go a mile deep or more to generate electricity. On a smaller scale, some buildings have geothermal heat pumps that use temperature differences several feet below ground for heating and cooling. Unlike solar and wind energy, geothermal energy is always available, but it has side effects that need to be managed, such as the rotten egg smell that can accompany released hydrogen sulfide.
Ways to boost renewable energy
Cities, states, and federal governments around the world are instituting policies aimed at increasing renewable energy. At least 29 U.S. states have set renewable portfolio standards —policies that mandate a certain percentage of energy from renewable sources, More than 100 cities worldwide now boast at least 70 percent renewable energy, and still others are making commitments to reach 100 percent . Other policies that could encourage renewable energy growth include carbon pricing, fuel economy standards, and building efficiency standards. Corporations are making a difference too, purchasing record amounts of renewable power in 2018.
Wonder whether your state could ever be powered by 100 percent renewables? No matter where you live, scientist Mark Jacobson believes it's possible. That vision is laid out here , and while his analysis is not without critics , it punctuates a reality with which the world must now reckon. Even without climate change, fossil fuels are a finite resource, and if we want our lease on the planet to be renewed, our energy will have to be renewable.
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Why renewables are the cornerstone of the global energy transition
Renewable energy, energy efficiency and electrification are key to energy transition Image: Dan Meyers on Unsplash
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- It's now clear that renewable energy, energy efficiency and electrification must be the drivers of the deep decarbonization we need.
- New analysis from IRENA finds that renewables are now the cheapest form of energy - and capacity is set to rise significantly over the next few decades.
Addressing climate change requires us to decarbonize both energy supply and demand by 2050. The US, Europe and China have committed to net zero or carbon neutrality by mid-century. Others are following suit. This will have a profound effect on the global energy transition, placing electricity as a key vector in decarbonizing the entire energy sector.
The latest insights from IRENA’s World Energy Transitions Outlook were released on 16 March at the Berlin Energy Transitions Dialogue. It provides in-depth analysis of what these effects will look like, starting from the Paris Climate agreement objective of limiting climate change to well below 2˚C and with an effort for 1.5˚C by the end of this century. While several options are being considered for a deep decarbonization, it is clear that renewable energy, energy efficiency and electrification are at the centre of the global energy transition .
Renewable energy and global energy transition
While climate change mitigation is a powerful driver behind the shift away from fossil fuel-based power generation, this is not the only driver. At the same time, renewable power has become the cheapest form of electricity generation and the costs continue to fall thanks to improvements in technology and economies of scale. The share of renewable power continue to rise from year to year, with nearly 30% renewables in the global power mix at present and renewables dominating yearly capacity additions (see Figure 1, below).
New IRENA analysis indicates a continued swift energy transition to renewable power generation worldwide in the coming three decades, with shares of variable (or intermittent) renewables – solar PV and wind – growing especially rapidly. Variable renewables will dominate the world's total power supply by 2050, a major change from today’s situation. Yet experience from around the world shows it is possible to operate power systems with high shares of variable renewables, as witnessed in Germany, Ireland and the UK, amongst others. During 2020, despite the COVID-19 pandemic, the share of renewables (mainly variable) in total electricity generation was 40% in Europe, a more than 4% increase in the share in comparison to 2019. Most notably, the share of other generation sources fell in Europe over the same period between 6% and 16%, as in the case of coal-based generation.
Increasing flexibility to smoothen energy transition
The operation of power systems with a high share of variable renewables requires much higher flexibility. Today, dispatchable fossil plants (that is, plants that can generate electricity on demand) provide that flexibility, but this will change going forward as their role declines. IRENA has identified 30 options for increasing flexibility across four main pillars : hardware, markets and regulations, and operational practices and business models (see figure 2, below). This toolkit of options must be deployed in the context of each power system’s specific characteristics. Especially the demand side offers interesting possibilities, as the electrification trend results in new loads connected to the system -such as electric vehicles, behind-the-meter batteries and heat pumps- which if operated smartly can support grid balancing. This is helped by rapid digitalization of power systems. Time-of-use pricing, aggregators, Demand Side Management are some of the strategies that benefit from digitalization and smart grids continue to expand worldwide. Still many transmission and distribution grids will require expansion and upgrading in order to deal with the new power system realities.
Also, regulations and grid codes need to be adjusted in order to enable to full deployment of the new flexibility options. This is an area that warrants more attention.
Electrification, including buildings, transport and industry, as well as the production of green hydrogen, will play a key role in a net-zero CO2 emissions future.
IRENA analysis suggests that up to a quarter of all electricity will be used for the production of green hydrogen . At the same time, a massive shift will occur towards electrification of road transportation while synfuels produced from clean hydrogen will play an increasing role in aviation and shipping. Whereas better building efficiency will reduce the need for heating and cooling, this is balanced by a shift to electric heat pumps. The analysis suggests that direct electricity use and indirect electricity use for the production of green hydrogen and derived synfuels may account for 60% of total final energy use by 2050, up from around 21% today. As a consequence, electricity demand will grow 3-4 fold from today’s level. This represents a massive shift; the electricity sector will become the central pillar of global energy supply and demand, a much bigger role than it has played in previous decades. Traditional incumbents in the energy sector, such as oil and gas companies, are already eyeing this trend and developing strategies to become electricity market players . It remains to be seen who will become the dominant player in this market in coming decades.
Moving to clean energy is key to combating climate change, yet in the past five years, the energy transition has stagnated.
Energy consumption and production contribute to two-thirds of global emissions, and 81% of the global energy system is still based on fossil fuels, the same percentage as 30 years ago. Plus, improvements in the energy intensity of the global economy (the amount of energy used per unit of economic activity) are slowing. In 2018 energy intensity improved by 1.2%, the slowest rate since 2010.
Effective policies, private-sector action and public-private cooperation are needed to create a more inclusive, sustainable, affordable and secure global energy system.
Benchmarking progress is essential to a successful transition. The World Economic Forum’s Energy Transition Index , which ranks 115 economies on how well they balance energy security and access with environmental sustainability and affordability, shows that the biggest challenge facing energy transition is the lack of readiness among the world’s largest emitters, including US, China, India and Russia. The 10 countries that score the highest in terms of readiness account for only 2.6% of global annual emissions.
To future-proof the global energy system, the Forum’s Centre for Energy & Materials is working on initiatives including Clean Power and Electrification , Energy and Industry Transition Intelligence, Industrial Ecosystems Transformation , and Transition Enablers to encourage and enable innovative energy investments, technologies and solutions.
Additionally, the Mission Possible Partnership (MPP) is working to assemble public and private partners to further the industry transition to set heavy industry and mobility sectors on the pathway towards net-zero emissions. MPP is an initiative created by the World Economic Forum and the Energy Transitions Commission.
Is your organisation interested in working with the World Economic Forum? Find out more here .
Given the growth in electricity demand and the shift to renewable power a massive expansion of clean power generation will be needed and infrastructure planning must be ramped up accordingly. The investment needs are hefty and it is critical to ensure that the infrastructure rollout speed is commensurate with the needs of the energy transition. This will require further streamlining of planning and approval processes.
IRENA continues to work with its 164 member countries to devise and implement renewable energy transition strategies for power sector transformation based on its Innovation Toolbox , Flextool , power systems planning and grid studies.
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Aerial view of a wind farm at Pen y Cymoedd in south Wales, UK. Wind-generated power in the UK increased by 83% between 2015 and 2020 to provide nearly a quarter of our electricity . It's also one of the fastest-growing renewable energy technologies globally. © Richard Whitcombe/ Shutterstock
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Renewable energy and its importance for tackling climate change
Replacing fossil fuel-reliant power stations with renewable energy sources, such as wind and solar, is a vital part of stabilising climate change and achieving net zero carbon emissions.
Professor Magda Titirici , Chair in Sustainable Energy Materials at Imperial College London, offers an introduction to renewable energy and the future of clean, green power in the UK.
What is renewable energy?
Renewable energy comes from sources that replenish naturally and continually within a human lifetime. Renewable energy is often called sustainable energy.
Major sources of renewable energy include solar, wind, hydroelectric, tidal, geothermal and biomass energy, which is derived from burning plant or animal matter and waste.
Switching our reliance on fossil fuels to renewable energy sources that produce lower or no greenhouse gas emissions is critically important in tackling the climate crisis .
Clean, green or renewable - what's the difference?
Clean energy doesn't produce any pollution once installed. Nor does green energy, which comes from natural sources such as the Sun and is produced without any major negative impacts on the environment. Renewable energy refers to sources that are constantly replenished.
While there is often overlap between these definitions and most renewable energy sources can also be considered clean and green, it's not always the case.
Nuclear energy doesn't release greenhouse gases into the atmosphere, so some people consider it to be clean - providing the radioactive waste is stored safely and doesn't escape into the environment. But the uranium energy source used in nuclear power plants isn't renewable.
A coal power plant emitting smoke, steam and carbon dioxide. Fossil fuels such as coal are non-renewable resources. Burning fossil fuels contributes to climate change by releasing greenhouse gases into the atmosphere. © Peter Gudella/ Shutterstock
What's the difference between renewable and non-renewable energy?
Non-renewable energy comes from natural resources such as coal, oil and natural gas that take billions of years to form, which is why we call them fossil fuels. They are present in finite amounts and will run out, as we are using them far more quickly than they form.
When will fossil fuels run out?
Research based on 2015 data predicts that coal stocks will last well into the next century, but oil and natural gas reserves (stocks that we know we can extract from) will run out in the late 2060s . However, scientific models suggest that if we are to limit global warming to 2°C - the target agreed at COP26 is 1.5°C - over 80% of coal, 50% of gas and 30% of oil reserves will need to be left untouched anyway.
When we extract fossil fuels from deep within the planet and burn them, we can generate electricity quite efficiently. But the process releases a lot of carbon dioxide (CO 2 ) into the atmosphere, which contributes to the greenhouse effect, global warming and biodiversity loss .
Magda explains, 'Fossil fuels brought with them immense technological progress but using them releases CO 2 into the atmosphere, which acts like a blanket, trapping heat that would otherwise escape into space and causing global warming.'
Did you know?
The energy sector is responsible for almost three-quarters of the emissions that have caused global temperatures to warm by 1.1°C since pre-industrial times.
If we continue to use fossil fuels, the effect will only worsen.
Magda adds, 'If we want to live on this planet much longer than 2050 and keep temperature levels below the 1.5°C of warming agreed to by governments around the world, we need to make some radical changes right now. We need to move to technologies that will give us the same level and comfort of living but drastically cut our emissions and carbon footprint .'
Examples of renewable energy sources
The main types of renewable energy are wind, solar, hydroelectric, tidal, geothermal and biomass. Read on to discover the pros and cons of each of these renewable energy sources.
One of the main benefits of most renewable energy sources is that they don't release carbon dioxide or pollute the air when they are used to produce electricity or heat. Greenhouse gases are emitted during the lifetime of some of the technologies - for example, during their manufacture or construction - but overall emissions are significantly lower than for fossil fuels.
Whereas some countries lack direct access to fossil fuels and must rely on international sources, renewable energy often allows countries to supply their own energy needs, a big economic and political advantage.
Wind energy
An offshore wind farm in the North Sea off the UK coast. Wind energy is an important renewable resource for the UK. According to analysis by Imperial College London's Energy Institute , offshore wind turbines offer the best-value option for meeting the UK's target of delivering carbon neutral electricity by 2035. But the UK's current target for offshore wind electricity production - up to 50 gigawatts by 2030 - will need to be significantly increased to do so. © Riekelt Hakvoort/ Shutterstock
Wind power converts wind - the movement of air - into stored power by turning turbines and converting mechanical energy into electricity. Wind farms can be built both on land and offshore. They work well wherever wind is strong and reliable.
Advantages: Wind energy is a clean, green and renewable resource and turbines can be placed on farmland with minimal disruption. It has the lowest carbon footprint of all renewable energy sources .
Disadvantages: Like any infrastructure, there is an upfront establishment cost and ongoing maintenance fees. These are even higher if wind farms are built offshore. Turbines have a reputation for being noisy and poorly sited wind farms can be dangerous to some wildlife - for instance, if they're placed in the migration paths of birds or bats.
How loud is a wind turbine?
At 300 metres from a dwelling, wind turbines have a sound pressure of 43 decibels , which is between the volume of a refrigerator and an air conditioner.
Solar energy
An array of solar panels in a field in Chippenham, UK. Solar energy is a renewable resource, and the Sun provides more energy than we'll ever use. If we could capture it all, an hour of sunlight would meet the world's energy needs for a year. © Alexey Fedorenko/ Shutterstock
Solar power captures energy (radiation) from the Sun and converts it into electricity, which is then fed into a power grid or stored for later use. Although places near the equator receive the most solar energy, solar panels can generate electricity anywhere that gets sunlight.
Advantages: Solar energy is renewable, clean, increasingly efficient and has low maintenance costs. Once established, it can dramatically reduce the price of generating electricity.
Disadvantages: Setting up a solar array is costly and there are expenses involved with energy storage. Solar panels can take up more land than some other types of renewable energy and performance depends on the availability of sunlight. The mining and processing of minerals needed to make the panels can pollute and damage the environment.
China is currently leading the world in solar energy production , with roughly 35% of the global market.
Hydroelectric energy
Although hydroelectric energy is renewable, it is not always considered green, as building large-scale dams can negatively impact the environment. Nepean Dam in Australia, shown here, was included in a study that showed dams are causing problems for platypuses by creating a barrier between populations. © Greg Brave/ Shutterstock
Hydroelectric power uses the flow of water, often from rivers and lakes controlled by a dam, to turn turbines and power generators, creating electricity. Hydropower works best for regions with reliable rainfall and large, natural water reservoirs.
Hydropower currently produces more electricity than all other renewable energy sources combined and provides around 17% of the world's energy.
Advantages: Hydroelectricity is dependable and renewable for as long as there is rainfall or flowing water. Reservoirs can offer additional benefits, such as providing drinking water, irrigation and recreational opportunities, including swimming or boating.
Disadvantages: Hydropower plants take up a lot of room and aren't suited to all climates. They are susceptible to drought. Creating artificial water reservoirs can harm biodiversity in natural water systems by limiting the inflow of nutrients and blocking the journey of migratory fish populations. These reservoirs can also release methane - a type of greenhouse gas - as vegetation in the flooded area decomposes. Large amounts of cement are used to construct dams. The manufacture of this material produces large amounts of carbon dioxide.
Tidal energy
Renewable tidal energy is produced by the natural rise and fall of the sea. However, tidal power plants can change the local biodiversity. This one on the River Rance in Brittany, France, not only led to the local extinction of a fish called plaice but to an increase in the number of cuttlefish, which now thrive there. © Francois BOIZOT/ Shutterstock
Tidal energy uses the continual movement of ocean tides to generate power. Turbines in the water turn a generator, creating electricity.
Advantages: Tidal energy is renewable, generates no carbon emissions and can produce a lot of energy very reliably.
Disadvantages: Offshore infrastructure is expensive to set up and maintain and there are a limited number of appropriate sites for tidal power plants around the world. They can also damage marine environments and impact local plants and animals.
Geothermal energy
A geothermal power plant in Iceland harnesses this renewable energy source. © Peter Gudella/ Shutterstock
Geothermal power uses underground reservoirs of hot water or steam created by the heat of Earth's core to generate electricity. It works best in regions near tectonic plate boundaries .
Advantages: Geothermal energy is highly reliable and has a consistent power output. It also has a relatively small footprint on the land.
Disadvantages: Drilling geothermal wells is expensive and can affect the stability of surrounding land. It must be monitored carefully to minimise environmental impact. There is also a risk of releasing greenhouse gases trapped under Earth's surface.
Biomass energy
A biogas plant producing renewable energy from biomass in the Czech Republic. © Kletr/ Shutterstock
Biomass energy comes from burning plants, plant by-products or waste. Examples include ethanol (from corn or sugarcane), biodiesel (made from vegetable oils, used cooking oils and animal fats), green diesel (derived from algae, sustainable wood crops or sawdust) and biogas (derived from animal manure and other waste).
Advantages: Abundant and cheaply produced, biomass energy is a novel use of waste product and leftover crops. It creates less emissions than burning fossil fuels and having carbon capture in place can stop carbon dioxide entering the atmosphere. Biofuels are also considered relatively easy and inexpensive to implement, as they are compatible with existing agriculture and waste processing and used in existing petrol and diesel vehicles.
Disadvantages: Generating biofuels requires land and water so growing demand for them could lead to deforestation and biodiversity loss. Burning biomass emits carbon dioxide unless carbon capture is implemented.
Ethanol-powered vehicles create up to 86% less greenhouse gas emissions than petrol vehicles, and crops that are grown to produce biomass absorb carbon dioxide.
Can renewable energy replace fossil fuels in the UK?
In 2020, 42% of the UK's electricity came from renewable energy. A quarter of the UK's electricity was produced by wind power, which is the highest proportion of any G20 country and more than four times the global average. Statistics on UK energy trends reveal that from April to June 2022, nearly 39% of the UK's electricity came from renewable energy, slightly more than during the same period in 2021, but down from 45.5% between January and March 2022 when it was unusually sunny and wind speeds were high.
'There has been good news in recent years in terms of progress on renewables,' says Magda, 'but in my opinion, the UK is still lagging behind. It is not so strong yet for truly sustainable technologies. It needs storage and conversion.'
Magda believes that wind (particularly offshore), solar, green hydrogen and rapid innovation in battery storage will be key to the UK reaching net zero by 2050.
She explains, 'The UK is a really windy place, so wind is the perfect renewable energy technology. By 2035 wind and solar should provide 75-90% of total UK electricity to bring emissions down significantly.'
'It has already been shown that it's feasible to produce 90% of the UK's electricity from wind and solar combined. The tech is there and it's becoming more efficient and affordable each year.'
'Offshore wind capacity will also help produce green hydrogen, another crucial part of the UK decarbonisation path.'
What is green hydrogen?
Green hydrogen is a fuel created using renewable energy in a process known as electrolysis. When green hydrogen is burned to produce energy, it releases water.
It's predicted that the UK will need 100 terawatt-hours of green hydrogen by 2035.
What is a terawatt-hour?
A terawatt-hour is a unit of measurement that's large enough to describe the annual electricity needs of entire countries. For scale, one terawatt-hour is equivalent to burning 588,441 barrels of oil.
The future of renewable energy in the UK
Magda believes the UK is at a very critical point in its sustainable technologies journey.
'Everything will depend on what happens this year and next. We need to see radical changes, investment, subsidies and support to reach our target of net zero by 2050.'
'It would cost less than 1% of GDP to get to net zero by 2050 but the advantages would be immense: new jobs, a sustainable economy and a healthy and resilient society.'
An empty electric vehicle charging point © Tony Skerl/ Shutterstock
Challenges and opportunities for renewable energy in the UK
One of the biggest challenges the UK is facing right now is battery storage and access to materials like cobalt and lithium , which are needed to produce lithium-ion batteries at scale.
Why are batteries important for renewable energy?
Batteries help make renewable energy supply reliable and portable - such as in the case of electric vehicles.
Batteries are an important part of our transition to renewable technologies, as they allow energy to be stored and released as needed. For example, solar panels generate energy during the day, and batteries make it possible to store and use that electricity at night.
Currently, just a few countries are responsible for most of the world's production of lithium.
According to Magda, the UK lacks access to the supply chain needed for Li-ion batteries. 'As a result, she adds, 'Johnson Matthey, which is a major company driving battery innovations in the UK, announced they would stop lithium battery research because they are unable to secure a path to raw materials and be competitive on the international market.'
Museum researchers are investigating whether it would be possible to develop a more sustainable, domestic supply chain by extracting lithium from UK rocks. They made a key breakthrough in 2021 when they produced battery-grade lithium chemicals from UK rocks for the first time.
According to Professor Richard Herrington, Head of Earth Sciences at the Museum, 'An increased, reliable supply of lithium is critical if we are to meet the rising demand for electric cars and provide a dependable supply of energy from renewable sources. The next generation of batteries that don't require lithium may still be three to five years away from being ready for public use.'
However, Magda is optimistic that the UK could lead in emerging battery technologies. 'I think the UK has an amazing opportunity to pioneer the next generation of batteries,' she says.
Innovative models already under development at The Faraday Institution include:
- Sodium-ion batteries, which are based on waste-derived anodes and critical metal -free cathodes, provide almost the same performance as lithium-ion batteries at half the cost.
- Lithium-sulphur batteries with 10 times the energy density of lithium-ion batteries make more efficient use of limited materials and eliminate metals from the cathode by using sulphur instead.
Magda adds, 'We need to focus on the areas where the UK has the potential to lead. The UK has such a big tradition in new materials and discoveries, we could move to completely new technologies both for batteries and hydrogen production.'
'There are a lot of challenges, but if we're investing in it, we could be future leaders and even solve one of the most difficult challenges in decarbonisation: flight.'
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