All of you consume over 80 gigajoules (GJs) of energy every year. For perspective: imagine leaving your washing machine on turbo at the highest temperature for a year straight. Assuming it had the endurance, it would deal the same damage to the environment. Referencing Quantum batteries by Quach et al. (2023), we learn that fossil fuel consumption accounts for 86% of the energy society depends on. Beyond this, in the 25-year period spanning 2015-2040, the energy demand is expected to increase by 28% globally. Since 1850, capturing from the early days of the American Industrial Revolution to today, the global temperature has permanently risen by 2 degrees Fahrenheit. "Permanently," as in according to NASA, it will take several centuries to even millennia to readjust. 

As it turns out, quantum computing shows major promise for helping combat the ongoing climate crisis. While we've spoken at length about its futuristic capabilities and implications, the potential of quantum computers to tackle the urgent challenge of climate change is often overlooked. The sheer complexity of developing sustainable solutions - from designing more efficient solar cells, to creating revolutionary battery technologies - demands computational power beyond the capabilities of even the most powerful classical supercomputers. The solution isn't solely about reducing our impact; we must proactively develop entirely new technologies and strategies for mitigation and adaptation.  Enter Queen Elsa, gloves off and poised to revolutionize our approach to environmental sustainability!

Classic Struggles

Our admitted overreliance on fossil fuels is directly linked to the limitations of classical energy storage. Think of it like this: though we have the potential to generate abundant clean energy from sources like solar and wind, we lack the robust storage systems to make it readily available when and where it's needed. We're trying to build a skyscraper on a sand dune. Current battery tech, while ever-improving, falls short of the energy density and recharge cycle times required for a legitimately sustainable future. We're trying to run a marathon on crutches. Quantum simulations can drastically accelerate the discovery and design of novel battery materials with superior performance. Instead of relying on trial-and-error experimentation, which is both time-consuming and resource-intensive, researchers can leverage quantum computers to explore a vast landscape of potential battery materials and configurations. This allows for the identification of materials with significantly enhanced properties, resulting in batteries that store substantially more energy within a smaller, lighter package - a crucial advancement for electric vehicles and portable electronics alike.

By simulating the complex interactions of atoms and molecules at the quantum level - a realm classical computers cannot reach - researchers can explore a vast chemical space far beyond the reach of traditional experimental methods. Furthermore, the accelerated design process promises batteries capable of significantly faster charging times, potentially reducing charging durations from hours to mere minutes. This improvement in charging speed is paramount for widespread adoption of electric vehicles and other battery-dependent technologies. Beyond increased energy density and faster charging, quantum simulations can also lead to batteries with a dramatically extended lifespan. By identifying materials and designs that are inherently more resistant to degradation, we can significantly reduce battery waste and the environmental burden associated with their disposal and recycling. Finally, a better understanding of the complex quantum interactions within battery materials, facilitated by quantum simulations, allows for the design of inherently safer batteries, minimizing the risk of dangerous overheating, fires, or explosions, leading to increased safety and reliability for consumers.

Maxwell's Got Some Demons

The Second Law of Thermodynamics - a cornerstone of classical physics: a closed space inherently tends toward disorder over time. More specifically - it asserts that this suggested entropy (the metric of chaos) tends to increase - not always. This indeterminant guideline, but statistical likelihood, stems from the fundamental mysteries surrounding the intersection of information, containment, and chaos which still elude us. This inherent tendency toward disorder is profoundly relevant to energy conversion and storage - as when energy undergoes conversion, the process is never 100% efficient. Consider any transformation - be it solar to electrical, or chemical to mechanical; some energy will be inevitably lost as heat, a byproduct of the increasing entropy of the system and its surroundings. This is precisely why your phone heats up during heavy use or rapid charging - it's a direct consequence of the Second Law. Classical batteries, in particular, are acutely constrained by such inefficiencies. Energy is lost both during charging and discharging cycles, limiting their overall performance, emitting carbon galore, and contributing to shorter lifespans.

This ambiguity and the unanswered questions surrounding the Second Law led the Scottish physicist, James Clerk Maxwell, to cultivate an abstract, gnostic argument: the Maxwell's demon thought experiment. Simplified, he imagined a tiny, intelligent being capable of manipulation at the molecular level: a "demon." This demon sits atop an adjustable bisecting partition, separating a container holding several "fast-moving" (hot) and "slow-moving" (cold) particles. The demon's role is to intuitively operate the partition like a gate, and group them by type - making one point hotter and one point colder within the single container - thereby sustaining a temperature difference in the singular environment and confronting the vague angle of the Second Law.

Maxwell's original intent was actually not to disprove the Second Law (which it didn't), in this regard, but to probe the very nature of the connection between information, energy, and the seemingly inevitable increase in entropy. However, the demon - like any of us - does not work for free. The processing of information in itself poses an energetic cost. In regards to the demon's memory, which requires continuous resetting - Landauer's principle likewise asserts that information erasure is also an energy-expending act. That alleged pocket demon is being put to work. This rendered a profound insight: that information is physical and has an energetic cost. This dialogue marked a turning point, highlighting the intrinsic limitations imposed by the Second Law - not as a barrier, but as a guiding principle of energy-information tradeoffs. The implications of this thought experiment far outweighed its immediate results. It triggered decades of debate on the relationship between thermodynamics and information theory, leading to profound insights into the fundamental limits of energy conversion and the role of information processing in physical systems.

This highly abstracted demon paradox laid the groundwork for quantum thermodynamics - chasing the interplay of classical thermodynamics as we know it, and quantum mechanical insights. This is where the implications for quantum computing become apparent. Quantum systems behave according to rules that differ fundamentally from classical mechanics. While we (thus far) cannot violate the Second Law, quantum mechanics offers a new locus of control to mitigate and reduce entropy more subtly and effectively. The development of quantum algorithms capable of finding optimal energy storage solutions is at the forefront of sustainability research, promising to mitigate the impact of the Second Law through technological innovation, offering a path toward a more efficient and environmentally responsible energy future.

Chasing Moby Dicke

The Dicke Quantum Battery is a fascinating, but convoluted achievement of engineering. Let's see if this may be the first ever actually digestible definition (wish me luck)! One qubit is good for emitting light. Yet, the addition of another is far more than twice as good. Let us analogize: have you ever seen the show Steven Universe? It's a musical Cartoon Network series, about a tribe of lesbian rocks bringing up a demi-human boy. Anyway - in that show are two characters, Sapphire and Ruby, who fall in love and fuse together to form Garnet - arguably the show's best character. Now, Garnet is a far more powerful gem - but noticeably different from both her "parents" in demeanor, power, and stature. This is to drive home - Garnet is not the sum of their parts, she is something that began where they both ended and soared exponentially. This same principle introduces us to the phenomenon of superradiance, the key of the Dicke battery.

So, translating this analogy directly - the two qubits interact within the contained electromagnetic field of the battery, and in their interaction emit an exponentially more powerful, superradiant light. The two come together, and the energetic response is off the chain - fair enough. The genius and difficult part to the Dicke battery is where the storage is happening: it's being stored in the reaction itself. By the time superradiance has been rendered, it no longer has anything to do with the individual qubits - it's just Garnet. The collective energy rendered by the qubits' excitation, contained and facilitated by their interaction within the field, is what enables the enhanced storage. The energy is effectively stored in the collective excitation of the system rather than being localized in individual atoms.  This innovative approach to energy storage harnesses the power of quantum mechanics, enabling faster charging and discharging and opening up exciting possibilities for next-generation energy technologies. The Dicke battery is not merely a collection of independent qubits, but a unified quantum system operating synergistically, showcasing the potential of quantum mechanics to revolutionize how we store and utilize energy. While challenges in scaling this technology remain, the Dicke battery demonstrates the potential of quantum mechanics to overcome the limitations of classical energy storage and dramatically improve the efficiency and sustainability of energy technologies.

We Might Not Burn!

In conclusion, the climate crisis demands innovative solutions, and quantum computing offers a powerful toolkit to address this urgent challenge. From accelerating the development of superior battery technologies, to investigating quantum physics' unique capabilities, to optimizing energy grids and designing more efficient renewable energy sources, quantum technologies hold immense potential for mitigating climate change's impacts. While significant hurdles remain in scaling up these technologies and developing the necessary algorithms, the progress made in quantum thermodynamics and materials science highlights the transformative potential of this field. The collaborative efforts of scientists, engineers, and policymakers are crucial to harnessing the power of quantum computing and building a more sustainable future.