The quantum energy initiative (QEI) is a recently launched initiative that wants to raise awareness about the energy consumption of quantum technologies and aims at making them more efficient and sustainable. However, I have been always skeptical about its mission and integrity. So, to get a clear picture, I thought it is best to talk to them and here you go. A big thanks to Raja Yehia for answering so patiently my questions.
About Raja Yehia: Raja Yehia is a postdoctoral researcher at ICFO (Barcelona) working on quantum communication theory. He is also a board member and part of the operations team of the QEI.
Required background: Non-technical familiarity with the quantum information hype.
Philipp: Dear Raja, many thanks for agreeing to discuss with me about the recently founded quantum energy initiative. To get started, I think the best would be if you explain what this QEI is actually about (having, say, a wider audience of physicists in mind who are not necessarily quantum tech experts).
Raja: Thank you for the offer to discuss with you. The QEI is a consortium of researchers that promotes research on the energetics of quantum technologies. Our community gathers experts from various origins, from fundamental quantum physics to technology, from hardware to software, from research to industry, caring for the physical resource cost of emerging quantum technologies and willing to address the question in a scientific way. This requires to build new methodologies, language, and roadmaps, and to create collaboration between scientific from different fields, such as thermodynamics and high-performance computing.
We are trying to raise awareness on the possible energetic costs of quantum technologies while they are still in an early stage of development. We believe that these questions should be raised as early as possible to avoid energy waste in the possible mass production of quantum devices. Path dependencies, where arbitrary decisions that have been made in the path constrain current technologies, have been observed in many areas of science and we believe the earlier we talk about these issues, the better.
The QEI operates through several formats: workshops or in-person events, social media communication about related job positions or news, and online seminars promoting specific research results. We have been highlighting, for example, work on the energy consumption of full scale quantum computers realizing some expected quantum algorithm. The QEI also communicates with the industry world and has more than 30 collaborations with different companies.
P: This sounds interesting and important, and I like to get into the technical details and challenges later on. But there is one thing stuck in my head from first hearing about the QEI. So, I hope you don’t mind if I ask the perhaps hardest question first.
As you know, there is a lot of public money in quantum technologies research, and at the same time selling things as “green” is also much en vogue. Then, how would you defend the QEI against the accusation of green washing? For instance, I was surprised that you hosted a 4.5 days workshop in Singapore with 2/3 of the invited speakers coming from at least 5000 km away (and I assume they did not come by bike).
So, to convince a notorious sceptic like me, I like to know: what convinces you that the net environmental effect of the QEI is positive? and what are the specific things you implement to avoid green washing (e.g., particular measures, policies, monitoring of success, moral or ethical commitments within the QEI, etc.)?
R: The QEI tries to create interactions between researchers from all over the world belonging to different fields that hardly ever talk to each other: fundamental thermodynamics, software engineers, different hardware platforms, high-performance computing and even classical information processing… It was important to create an in-person event to launch the initiative and give it the first push. We managed to gather around the same table people from all of these fields and it actually proved very fruitful. All their different inputs gave us a roadmap of all the aspects to study about the energetics of quantum technologies, while a year ago there was practically no research on the topic.
Moreover, the QEI actions go beyond this workshop. We try to favor online presence, and we organize periodic online seminars that are all available on our YouTube channel, along with most of the talks from the workshop. We also have the ambition to make our website a platform where relevant news, job positions or scientific videos are advertised. We try to have a social media presence to counterbalance the greenwashing wave that you described within quantum technologies. Lastly, and maybe more importantly, we are actively trying to define standards and metrics that could be used by the community to estimate the energy cost of their devices or software.
We hope that, in the long run, our efforts will help to avoid some energy waste in the industrialization of quantum technologies. We avoid greenwashing by addressing the questions in a scientific way and we have implemented internal policies to try to avoid being used by political or industrial groups as a “greenwashing stamp”. Our goal to raise awareness on the possible energetic consumption of future quantum technologies precisely counterbalances the myth that quantum technologies will save us from climate change.
I would also like to make clear that our objective is not to advocate for or against quantum technologies as a green technology, but to scientifically estimate the energetic consumption of different quantum technologies. Hopefully, our findings will be used to take informed decisions about what platform to use or what protocols to avoid.
P: Glad to see that you mentioned the possible “greenness” of quantum technologies. I actually planned to address this later, but let’s discuss it now.
So, it doesn’t take much effort to find hundreds of sources that praise quantum technologies (in particular quantum computers) as “green”. McKinsey even suggests that quantum computing will save the planet. To me this sounds like the perfect opium of the people (and of scientists): let’s simply not care now because eventually we will have the magic technology that saves us all, yeah! Moreover, if it were true that quantum technologies will make everything green by default, then the QEI would be a futile exercise, right?
So, you already indicated that you are a bit more sceptical here. Could you elaborate further on what’s behind “green quantum tech” and how the QEI thinks about it?
R: To my understanding, ‘green quantum tech’ is a vague term that encompasses both quantum technologies offering an energy advantage compared to classical technologies and applications of quantum technologies that could help mitigate the effect of climate change. Just like ‘green finance’, I believe that it is mostly a political wording without necessarily a strong scientific basis, used to attract investors and promote the field.
In the QEI, we avoid using this formulation and try to focus on the rigorous estimation of the energetic cost of quantum technologies. In fact, we are not looking at the possible applications of quantum technologies, we only concentrate on raising awareness on the intrinsic cost of these technologies. Only by creating figures of merit and benchmarks will we be able to say if a particular quantum technology can be called ‘green’ in a particular context. Without being completely oblivious to possible energy advantages given by quantum technologies, we want to take a scientific approach and thus avoid vague formulations that could create confusion. Claims such as McKinsey’s are precisely what motivated some of us to join the initiative, to partly prove or disprove them through rigorous study.
P: Okay, to summarize, you prefer to focus on the intrinsic costs of quantum tech instead of asking for what purpose to apply them. But as far as I understand, the QEI not only likes to estimate the energy consumption, but you like to research ways to increase the efficiency of quantum tech. Three of the four main goals of the QEI manifesto are related to improved energetic efficiencies, and also Alexia Auffèves writes in the abstract of her perspective that launched the QEI that this “is the only path towards energy-efficient, sustainable quantum technologies”. I like to question the words “only” and “sustainable”.
Have you heard of “Jevons paradox“? After James Watt introduced his novel and much more efficient steam engine, the English economist William Stanley Jevons made the surprising observation that the consumption of coal did not decrease but increased! More broadly speaking, the fact that increased energy efficiency leads to increased energy consumption is known as the Khazzoom-Brookes postulate. Of course, there is nothing paradoxical about this given the current economic system: companies are not interested in energy efficiency for the purpose of saving energy, but for the purpose of producing more in a cheaper way, to leverage the profit margin.
Now, even if the QEI miraculously manages to make quantum tech 90% more energy efficient, it will only increase the energy (and material) consumption at the end. What is your takeaway message here? I am not able to find any statement from the QEI about that. Do you plan to announce that quantum tech should be only used in a degrowth scenario or that the amount of quantum tech should get publicly regulated and limited?
R: This paradox is an extreme version of the rebound effect: when a more efficient technology arises, people tend to use it more resulting in an increase in the final energy consumption. This is now a well-known effect that industrials and politicians should be aware of when putting new technologies on the market. We discussed it extensively during our last workshop but it appeared to be out of the reach of our scientific knowledge. To correctly estimate the amplitude of the rebound effect for quantum technologies would require extensive collaboration with social sciences and is, for now, out of the scope of the QEI.
We do try to collaborate with social scientists, as you can see in our YouTube seminar series, and to raise awareness on this issue as well. But, at the risk of repeating myself, the QEI’s research focuses for now on the rigorous estimation of the energy cost of quantum technologies. We are not here to say how and why these technologies should be used. We can only hope that the data we provide will be used correctly by political bodies and industries and that they will be conscious of the energetic cost of the device they put on the market. In its current vision, the QEI will not announce anything about how quantum technologies should be developed. Individually, however, members of the QEI might very well get involved in more political groups and try to do lobbying in one way or another.
P: While I agree that this “rebound effect” is hard to estimate, I am disappointed about the conclusion. I think industrials or politicians probably know that technologies consume energy, but that more efficient technologies consume even more energy does not seem to be on their agenda. But independently on what they know, my point is that it does not even matter: there simply is no measure you can take within our “eternal exponential growth economy” that prevents this rebound effect. I had hoped that such an important warning would be transparently communicated, in particular since you confirmed that the QEI is (thankfully) aware of it.
While I am happy to discuss this further, you actually surprised me most with the statement that “the QEI’s research focuses for now on the rigorous estimation of the energy cost of quantum technologies”. I (probably naively) thought from reading your Manifesto that you also want to do research on improving the energetic efficiency of quantum technologies, and perhaps even find a quantum energetic advantage. Did I understand it wrong or did you switch (or perhaps postpone) these goals?
R: As you said at the beginning of this interview, there are a lot of claims about the ”greenness” of quantum technologies which raised several interesting research questions. For example: Will quantum technologies really help mitigating climate change given that they also have an intrinsic cost? Is there any energy advantage of using quantum technologies over classical analogues? How to improve the efficiency of quantum technologies? Is there a fundamental cost, or a lower bound to the energetic cost of quantum algorithms? These are challenging questions and there are many others along the same line. While some people seem to already have an opinion for some of them, there is no scientific consensus. The QEI is here to help answering these questions, by creating and promoting the tools, benchmarks and data that will allow informed discussions on the topic. The rigorous estimation of the energetic cost of quantum technologies and establishment of methods to analyse it is simply the first step to be able to answer these questions. Many research lines are taken independently and the QEI is not setting them, rather promoting them.
P: I guess that’s a good point to get a little more technical in our conservation. As far as I can tell, many members of the QEI come from quantum thermodynamics, a very theory-dominated field somewhere between quantum technologies and statistical physics.
Now, even though it doesn’t get publicly acknowledged, every person I’ve talked to confirmed that the theoretical framework of quantum thermodynamics neglects most thermodynamic costs related to the experiment: fridges, lasers, traps, electronics, etc. Moreover, given that fridges and lasers and all this are quite old technologies that have been optimized for decades, the history of science teaches us that we shouldn’t expect giant efficiency improvements for these technologies in the near future.
In light of this it seems that wondering about fundamental costs or quantum advantages of algorithms, which will be dominated by these external costs, is a waste of time for the QEI with its clear practical mission. And please don’t get me wrong here: I think it is intellectually extremely stimulating to think about this, but betting on this as a way towards sustainable, eco-friendly quantum tech sounds like searching for the parachute after you jumped out of the plane.
So, I feel that the QEI needs full stack engineers and no physicists. Do you agree? Do the members of the QEI plan to become engineers? Or do you think that you can seriously contribute to a quantitative estimate of the energy costs of quantum tech by writing down a Hamiltonian and a Lindblad master equation?
R: As one of our founders puts it, I believe that the question of the energy cost of quantum technologies is an unexplored tunnel with two sides: one is the fundamental, thermodynamic and theoretical cost of quantum information and the other one is the practical, “real” cost of quantum devices including fridges, control electronics, classical optimisation or post-processing, and everything around the quantum machines. Both sides are important as the former gives lower bounds and help us understand more in depth the energy aspects of quantum information, while the latter gives more practical benchmarks and gives information about the feasibility of quantum technologies. If you look more precisely at the QEI community, or at the talks that we had in our workshop or on our YouTube channel, you will see that the two sides are tackled almost equally. For example, the first work that we promoted on our QEI Seminar series precisely tries to account for the external costs of a scalable superconducting-based quantum computer, by including control electronics, wiring, and cryogeny in the estimation of the cost of running simple quantum algorithms. This is also a reason why we include industry partners in the community, since they are more on the engineering side as you put it.
On the other hand, we also believe that research on the fundamental, thermodynamic side will help us create methods and benchmarks that will be valid for any technology. The QEI is precisely here to help those two sides meet, and create a community beyond the usual engineering/researcher separation.
P: Okay, then let’s talk about a few numbers. Where do we stand right now? What are the current energy costs of quantum tech (perhaps relative to the costs of classical computation)? What’s the cost ratio between manufacturing these technology and actually using them? How do you expect these numbers to change in the next 5 or 10 years?
R: For the almost 3 years that the QEI has been around, we have been pushing the community as well as our industry partners to investigate the energy consumption of their setups. It is slightly too soon to give precise numbers, as we are still in the process of developing frameworks to estimate the energy cost of quantum technologies. Once a method is fixed, we will be able to apply it to the different architectures that exist. As with classical technologies, it is challenging to have a complete picture to estimate the cost of full scale architectures. It is not so easy to get the cost of a super-computer or the consumption per hour of the Internet, and the same goes for quantum technologies in all its diversities. This is precisely why we need more researchers and engineers to get interested in the topic. We invite the interested reader to participate to this effort by joining the IEEE Working Group, where a global effort is developing a standard for Quantum Computing Energy Efficiency.
We expect that our initiative, among others, raises awareness around the issue, and that we will get answers to these questions soon. I also hope that the energy cost can be a guiding light in the design of quantum technologies, and that these numbers will lower in the next decade.
P: Okay, to finish the discussion, let me ask you which of the following three future scenarios you find most realistic, and which of them would you personally prefer to happen:
(a) In ten years all the quantum computing hype will be over and even politicians learned that quantum technologies are only useful for some niche applications. Owing to the very low demand of quantum technologies, there is no need for any QEI.
(b) In ten years we will have powerful quantum technologies, which are extremely efficient thanks to the efforts of the QEI. Unfortunately, owing to the fact that we didn’t learn to regulate our growth and consumption, we have then also reached multiple tipping points that subsequently result in a loss of 99.9% of the biosphere.
(c) In ten years humanity has learned to use quantum technologies wisely and applies them rarely when the total benefit-cost ratio for planet Earth is positive. There is no need to work more than 20 hours per week, and you dropped out of the QEI to have more time for growing tomatoes in your garden.
R: You may have forgotten another realistic, yet undesirable scenario: Access to quantum technologies will be confined to advanced economies and will widen the wealth gap between them and lesser developed nations who do not share privileged security agreements with them. This will lead to domestic political pressure in those countries to forgo environmentally sustainable development while they rush to catch up… However, over these three unrealistic scenarios, I would maybe favor (c), mostly because I would have a garden then! I would also personally be in favor of reducing working time per week, as well as ensuring basic needs for everyone, but this is out of the scope of this interview. 🙂
I do agree with what you imply in your scenarios: our current growth oriented economical model is not compatible with keeping our planet habitable for humans. I wouldn’t know about the rest of the biosphere, some insects and plants are more resilient than us. Hopefully, the QEI will provide more scientific data to back up these statements!
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