Cop 26 has certainly been focusing the minds of politicians, economists, industrialists, and consumers alike. And indeed the Italian prime minister, Mario Draghi, called for a ‘quantum leap’ on climate change. Unwittingly perhaps he may have pointed to one of the solutions.
Climate change is one of the greatest challenges we face. To avoid the worst effects of climate change, such as severe droughts and collapsing ecosystems, we must move to net-zero emissions of greenhouse gasses in 2050. At the current pace, 51 billion tons of greenhouse gases are added to the atmosphere every year. To get to net-zero, we need to change our behaviour, we need new legislation, and we need new technologies.
We will need all types of technologies to achieve that. One type of technology though, is particularly interesting. Running quantum computers can reduce emissions because they are more energy efficient than large supercomputers clusters and can thus save energy consumption. However more importantly, quantum computers can be used in research to develop and evaluate the technologies that we need to get to net-zero. Quantum simulations, in chemistry, material science, or pharmaceuticals, can exponentially speedup the simulations (compared to classical computers) that we would need to invent better solar panels, industrial processes, and electric vehicles. Given the enormous potential of quantum computers, it is worth exploring if quantum technology can help in our ambition to get to net-zero emissions.
To explore how quantum computers can assist, I’ll start with an overview of where our emissions come from. I borrowed these statistics from the book „How to Avoid a Climate Disaster” by Bill Gates. From the 51 billion tons of CO2equivalence, almost a third (31%) comes from the way we build or make things. Although most of us are most aware of climate policies related to transportation (such as subsidies on electric vehicles) or plugging in (solar roof panels), the way we make things is more than four times more polluting than emissions from keeping us warm and cool. Electricity generation (through coal, gas, sustainables, or others) accounts for 27% of global emissions, getting around (either through cars, planes, or ships) accounts for 16%, and growing things (agricultural processes) account for 19%.
Technology breakthroughs in the past have made some sustainable practices within reach. Solar panels, for example, have decreased 90% in price over the past ten years, and are now, in some countries, competitively priced with conventional electricity generation. That is, if the sun is shining. Other industries, such as concrete fabrication, have found it to be a lot harder to reduce emissions. Green premiums, the added costs of replacing conventional methods with carbon-free manufacture, are highest in concrete fabrication. To get to zero emissions here, we will need technology breakthroughs that drive down the green premiums. Quantum computers, through its potential of exponentially speeding up simulations, can play a significant role in discovering and accelerating these breakthroughs.
A Quantum advantage in producing electricity
Let’s look at some of the most meaningful ways in which quantum computers can do just that, starting with the way we produce electricity. Electricity production accounts for 27% of greenhouse gas emissions and without significant governmental and commercial interventions is likely to double in the next decade. We need sustainable ways to produce it, and we need to use less where possible. To produce clean energy, we need to move to renewables (such as solar, wind, tidal and biomass) and nuclear. Renewables, such as wind and solar, however, only provide energy when the sun is shining and the wind is blowing, subsequently requiring storage and flexible grids.
I believe that there are three important ways quantum computers could support the supply side of electricity:
· More efficient solar panels. Current, conventional solar panels have a maximum efficiency of around 15%, while theoretically limited to 23%. Quantum computers could help through simulations of novel photovoltaic materials, such as quantum dots, or perovskites that either improve the efficiency, or reduce the costs of manufacturing.
· Efficient energy grids. The variability of sustainable energy sources puts considerable pressure on energy grids. Quantum algorithms could help in optimisation, planning, and logistics of grids, as well as simulations to forecast, and to balance the load. In addition, quantum simulations could help in discovering new materials, such as high temperature superconductors, with better conductive properties.
· Development of next-generation nuclear power. Next-generation nuclear fission or nuclear fusion are promising energy sources without any emissions. Nuclear fusion, in particular, promises almost infinite energy, without any radioactive waste or emissions. Developing next-generation nuclear power, however, is extremely complex and typically relies on large computer models. Quantum computers can speed up the process with simulations of new materials (such as high temperature superconductors), or high energy particle physics.
A quantum advantage in the way we make things
Another big part of greenhouse gas emissions come from the way we make things, adding up to a total of nearly a third (31%) of total emissions. Emissions arise in all parts of the production supply chain, however, emissions from steel, cement, and plastic production are particularly interesting to explore with quantum computing, because they are so ubiquitous. Also, the production processes of these materials pollute significant emissions because of the vast amount of electricity required to keep the factories running, the heat needed to trigger chemical reactions and the carbon that is released during chemical processes itself.
However, there are various ways in which quantum computers can help manufacturing:
· Stronger concrete, so that less can be used. One way to reduce the environmental impact, is to produce ultra-strong varieties, such that less concrete is required to do the same job. Stronger concrete can be made by using quantum simulations to find the right combination of polymers. According to Karen Scrivener, Head of the construction laboratory at the Swiss Federal Institute of Technology, „This will be the quantum leap everybody is trying to achieve. I’d say, on a five-to-10-year basis, we might be able to fundamentally change the properties of concrete on a nanoscale.”
· Hydrogen powered steel production. The primary cause of emission in steel production is related to getting the required temperature in the fabrication process. Currently, this is done by burning coal, which is among the most polluting fossil fuels. However, quantum simulations could help in finding better and more efficient catalysts for hydrogen production, and hence would reduce the costs of hydrogen.
· More efficient supply chains. Global supply chains suffer from inefficiencies due to their complexity. Quantum optimization algorithms could potentially help in optimizing routing networks, efficiently scheduling resources, and forecasting demand and supply. Although a quantum advantage for this use case is less clear than for other cases, only a few percent improvement would have a dramatic environmental and economic impact.
A quantum advantage in the way we grow things
Third, the way we grow things adds up to 19% of total emissions. There is a large variety in the origin of emissions related to the food that we produce. Part of it is emissions related to industrial processes, such as the production of fertilizer, while others are related to methane emissions in meat and dairy production or related to deforestation for agricultural purposes. There are also many opportunities to reduce emissions, or even sequestrate greenhouse gases in agricultural processes. There is a huge gap in agricultural productivity between the developed world and some parts of Africa (the yield in Africa per square meter for corn is on average a tenth of that in the US), suggesting a huge potential to improve agricultural sustainable land use. The following use cases are particularly promising.
· More efficient fertilizer production. The polluting part in fertilizer production is the fixation of nitrogen through the century-old Haber-Bosch process, which requires high pressures and temperatures. In the process, nearly 2% of the global energy is consumed. On the other hand, the naturally occurring nitrogenase enzyme fixates nitrogen at room temperature and pressure. Understanding the working of nitrogenase is out of reach of current classical systems but would be feasible with medium-term quantum computers. Ultimately, quantum computers could help in the development of nature-inspired industrial catalysts.
· Carbon sequestration in agriculture. The total potential of carbon sequestration (putting carbon back in the ground) through sustainable agricultural practices is between 300 and 400 giga tonnes, almost ten times the world’s emissions in 2021. Quantum simulations of plant genomes could potentially improve characteristics such as resilience to weather conditions or the yield of crops, so that farmers can apply sustainable practices, or give agricultural land back to nature.
A quantum advantage for mobility
And finally, the way we get around amounts to 16% of total emissions. Although electric car sales have picked up drastically in past last few years, the stock of plug-in electric vehicles represented just 1% of all passenger vehicles on the world’s roads by the end of 2020. Additionally, other means of transport such as planes, ships, trucks, and busses will be more difficult to electrify. The following are two particularly interesting quantum computing use cases.
· More attractive electric vehicles. A major hurdle for the adoption of electrical vehicles is the limited capacity, degradability, and time to charge of batteries. Quantum algorithms could help in the development of high-capacity lithium (metal) batteries. Daimler and IBM have already been working on improving the capacity and speed-of-charging of lithium batteries, using a quantum computer to model the next generation lithium sulfur (Li-S) batteries that would be more powerful, longer lasting, and cheaper than today’s widely used lithium-ion batteries.
· Hydrogen powered heavy transport. Electric propulsion will likely be impossible for heavy transport such as planes, ships, and long-haul trucks. Instead, hydrogen could be used. Quantum algorithms could be used to develop more efficient industrial catalysts for hydrogen production and storage.
Let me stress, quantum technology, or even technology as a whole, is not the sole solution to the climate crisis. To get to net-zero, we will need a vast variety of behaviour change, legislation, research, incentives, and investments. Frankly, there is no time to waste. We cannot permit ourselves to wait for quantum computing, which may still be 5, 10 years or even further out. However, we must also plan for future challenges. We must acknowledge that we do not have the technology ready to replace hard-to-transition industries such as steel and cement production. While we should adopt solar and wind power massively today, we should invest in research into the smart grid, and alternative energy sources for tomorrow. Quantum computing, as one of the most disruptive technologies of the 21st century, may provide a strong advantage in developing the breakthrough technologies that we will need.