One of the most interesting — and timely — areas of research for quantum technologies is combating climate change. The renowned quantum physicist, Richard Feynman, said, “nature isn't classical, dammit, and if you want to make a simulation of nature, you'd better make it quantum mechanical, and by golly it's a wonderful problem, because it doesn't look so easy.”9 There is already substantial activity at the intersection of quantum and sustainability. Three high-level examples of where quantum technologies may offer a step up in capability for reducing carbon emissions are: simulation, optimisation and modelling, and quantum sensing.10
Let us consider each of these in turn.
Quantum-enabled simulation is widely applicable across sectors, with use cases ranging from the discovery of more environmentally-friendly battery materials and chemical compounds that can facilitate carbon capture, to supporting the design of more energy-efficient vehicles.
For example, the complexity of simulating even simple molecules and their interactions using classical computers has created barriers for materials science in the past because the computations would take too long to be practically useful. Historically, this has delayed innovation in areas that are key to societal advancement, such as drug discovery and manufacturing.
Recognising the promise of quantum computing in overcoming previous computational limits, IBM and Daimler are collaborating to develop “next-generation lithium sulphur (Li-S) batteries that would be more powerful, longer lasting and cheaper than today’s widely used lithium-ion batteries”.11 Such efforts have the potential to create a positive impact on consumers, manufacturers and most importantly, the planet.
Optimisation and modelling
Sustainability can also be a byproduct of organisational optimisation. In our research, we have identified opportunities for quantum-enabled optimisation in areas such as waste collection, traffic management, flight path management, logistics, supply chain, stowage, and energy consumption.
For instance, Fujitsu and Toyota have experimented with a quantum digital-annealer solution on their manufacturing supply chain, which they reported could “reduce logistics costs by two to five percent.”12 Furthermore, Cambridge Quantum Computing — now Quantinuum — and Deutsche Bahn have partnered to use quantum computing to make the German rail network greener and more efficient.13
These types of problems are known as combinatorial optimisation problems, which can be thought of as efforts to locate an ideal solution in high-dimensional data.14 Combinatorial optimisation problems scale rapidly in complexity, as the number of variables increases. Like the impracticalities of running complex molecular simulations on classical computers, combinatorial optimisation problems can also quickly become too burdensome for classical computing infrastructure, which makes quantum computing an obvious opportunity for innovation. Quantum optimisation allows businesses to reduce costs, maximise efficiency and reduce environmental impact, if not augment overall sustainability.
A third area of opportunity for quantum and sustainability is quantum sensing, which, according to the Networked Quantum Information Technologies Hub (NQIT), leverages the quantum mechanical properties of subatomic particles to augment “precision when estimating a parameter of a system.”15 In simpler words, quantum sensing can help us to understand better the world around us by giving more detailed, precise information about an object or phenomenon of interest.
In contrast to their classical equivalents, quantum sensors promise to be much more sensitive because of the fragility of quantum states, which are highly susceptible to changes in their environments. By virtue of that sensitivity, quantum sensors have the potential to be more useful in helping decision-making in use cases across sectors — from life sciences to manufacturing.
The work of the HYDRI consortium — led by BP — is a good example of how quantum sensing can be harnessed for sustainability. The consortium aims to create quantum sensors to detect hydrogen gas leaks.16 This work is a part of broader efforts to promote the use of hydrogen gas as a greener energy alternative. Away from detecting potential environmental hazards, quantum sensing can also be used to monitor carbon emissions more reliably, as well as improve the performance and longevity of certain renewable energy sources, such as wind turbines, by enabling real-time turbine adjustments according to weather conditions.17