By Dana Nuccitelli
The great transition from a fossil fuel based economy to a green economy is underway. It will involve a sea change in the way we generate and use energy for various purposes. Instead of drilling for and mining for fossil fuels, we need to mine for critical minerals to make a whole host of “clean” technologies like solar panels, wind turbines, and batteries.
This raises some general questions – if we consider the impacts of mining and manufacturing these technologies, are they really better for the environment, human rights and climate than the fossil fuel alternatives they replace?
In general the answer is yes. Clean technologies will have a non-zero impact, but they will be much smaller than the dirty fossil fuel status quo.
Which requires more mining – fossil fuels or clean energy?
The short answer to this question is that fossil fuels require much more mining and drilling than clean energy technologies. Today, 8 billion tons of coal are mined globally each year, while the clean energy transition is estimated to require around 3.5 billion tons of minerals overall over the next three decades.
A December 2021 paper Researchers from Rice University tried to answer this question in detail. Among the clean energy technologies, wind turbines in particular require a significant amount of minerals per amount of energy produced, as shown in the graph below by the International Energy Agency.
But this table only shows the minerals needed to build the power plants. Once a wind turbine or solar panel is built, no further mining is required. Nature provides its fuel (wind and sunshine). Fossil fuels, on the other hand, require continuous mining or drilling to obtain new fuel to burn.
For example, in 2020 alone, almost 8 billion tons of coal were mined worldwide and over 4 billion tons of crude oil was extracted from the ground. That’s more than the 2.6 billion tons of iron ore mined for steel making, which dwarfs all other mineral mining as shown in the graphic below. For comparison, World Bank estimates that a way to reach the Paris targets would require nearly 3.5 billion tons of minerals in total over the next three decades.
It’s a bit more complicated than this comparison because some minerals, like rare earth metals, have to move a lot of earth to get a bit of the substance you want. With that in mind, the Rice study estimated that generating power from wind turbines in Texas would require five times less earthmoving and waste than an equivalent amount of coal-fired power.
In addition, the environmental impact of mining is relatively limited to the area surrounding the mine. However, burning fossil fuels creates additional air and water pollution at the power plant, greenhouse gas emissions and the risk of spills during fuel transport, creating a larger geographic pollution footprint. causes air pollution about 250,000 deaths per year in the USand almost 9 million per year worldwide, especially in disadvantaged regions and communities. Conversely, a solar fuel spill is also known as “a beautiful sunny day.”
Finally the recycling of solar panels is now ready to take off as the materials become more valuable due to the growing solar demand. Similarly, wind turbine blades have mostly been discarded as waste (although most wind turbine material is recyclable), but progress is made in recycling or conversion also the blades. Recycling old materials will reduce the need to mine new minerals over time.
Don’t renewable energies take up a lot of land?
Wind farms can take up a large amount of land overall, but the space between individual wind turbines can be used for a variety of purposes.
The map below from Princeton’s Net-Zero America report illustrates the total land area required in a possible 2050 clean energy scenario. Overall, the report estimates that 60 to 270 million acres will be needed for clean energy. For comparison the Leasing contracts for the oil and gas industry nearly 26 million onshore and 15 million offshore federally owned acres and nearly another 30 million acres of private and state owned land.
However, 99% of the large blue wind farm footprint shown above represents the remote area where only wind turbines originate visible. Most of the land around wind farms and even the land between individual wind turbines can be used for other purposes such as growing crops or grazing animals. The physical footprint of the wind turbine equipment is represented by the small dark blue square in the figure above. The Net Zero Report predicts that more than 10% of solar panels could be installed in the built environment (e.g. on rooftops and parking lots), and they can provide shade for some crops on farms.
The Princeton Net Zero report estimates that the clean energy transition will require about 10 million acres of land for the solar panels and wind turbines themselves. The USA is currently used for comparison 38 million hectares to grow crops for corn-based ethanol and biodiesel and has paved 39 million acres for roads and parking lots.
Are electric vehicles (EVs) better for the environment?
Based on today’s average US grid mix, driving an electric vehicle produces greenhouse gas emissions equivalent to a gasoline-powered car at 88 miles per gallon (mpg).
An analysis found by the Union of Concerned Scientists that even in the regions with the dirtiest power grids, driving an electric vehicle produces the same greenhouse gas emissions as a 39-mpg petrol car. As the map below from the report shows, driving an electric vehicle has lower carbon emissions than a 100mpg petrol car in many regions. And those numbers will only improve over time as the grid gets cleaner.
People often wonder about the extra emissions associated with manufacturing EV batteries and the extra weight they add to the vehicle. These are called “indirect emissions” but to make a fair comparison we also need to consider the indirect emissions from petrol cars – drilling, refining and transporting oil.
A study from 2021 did just that and found that all indirect emissions were indeed accounted for further reduces the carbon footprint of electric vehicles compared to those of petrol-powered cars, as constantly producing more petrol generates more greenhouse gas emissions than manufacturing and charging EV batteries.
What about the environmental impact of mining minerals for EV batteries?
Mineral mining certainly causes local adverse environmental impacts, but overall oil drilling, refining and transporting is worse.
lithium mining can have significant adverse effects on the environment, but there are potential solutions to these problems. For example, water pumped underground to generate heat in geothermal power plants can supply lithium much less polluting than mining. Development is also progressing Sodium Ion Batteries; sodium is one of the most common elements on earth and can be obtained from sea water. Researchers are too Finding ways to greatly improve lithium batteries to make them smaller and lighter, thus using less mined material.
Importantly, while we will need significant mining of minerals to meet growing battery demand in the coming decades, the Metals in batteries can be recycled. In the future, much of the minerals needed for clean technologies will be provided through recycling rather than further mining of natural resources. EV batteries also have took much longer than expected – essentially the entire lifetime of a vehicle – and after that it can be used for power grid storage.
As Kwasi Ampofo, Head of Metals and Mining at BloombergNEF said about new solutions to mining problems: “Human ingenuity knows no bounds.”
What about the human rights impacts of mining?
Mining minerals in countries with lax regulations can lead to human rights violations, but researchers and industry are finding alternative solutions.
A big problem is cobalt, which is needed in lithium-ion batteries. About 70% of the world’s cobalt supply and almost half of the known global reserves are from the Republic of the Congo. A lack of regulation has led to hazardous mining conditions there, often involving child labour.
But there are solutions to these problems. Battery manufacturers can source materials from places with strict environmental and human rights standards. Australia’s cobalt industry has increased as manufacturers look to alternative sources. Researchers are also constantly developing new battery technologies. Lithium iron phosphate batteries do not require cobalt and are already in widespread use. be used Almost half of China’s electric vehicles and half of Teslas were sold in the first quarter of 2022. There are also some successes in use widespread manganese instead of cobalt for lithium batteries.
We can always do better
Clean energy technologies will always have non-zero climate and environmental impacts. The best solution is to use less energy and material in the first place. Rather than simply replacing petrol-powered cars with electric vehicles, we should also try to reduce car use through better city planning and public transport overall. Walking and cycling (including electric bikes and scooters, aka micromobility) and bus and train travel all have significantly lower environmental impacts than driving a car. And weathering buildings can reduce their energy consumption by a third.
Therefore, it is ultimately better for the environment to adopt clean technology today than to endlessly mine, drill, refine, ship and burn dirty fossil fuels while working towards using less energy and materials in the long-term.