"We want to build 60 billion chips in the ten to 15-year range,” Rodolfo Rosini, CEO of Vaire Computing, says with complete sincerity. “The question is whether they are all going to be made by us or licensed out.”

To put it another way, whatever Arm is currently shipping, Rosini wants Vaire to do better.

Founded in 2021 and based in London and Cambridge in the UK and Seattle, Washington in the US, Vaire Computing is a reversible computing startup developing what it calls “near-zero energy chips,” a term that Rosini says was coined by the company and which it prefers to the industry accepted term of “resonant adiabatic reversible computing.”

In about five years time, Rosini believes Moore’s Law will hit a wall, at which point the only way to increase compute power will be by increasing water and energy usage. Vaire wants to decouple energy and water resources from the compute growth, allowing for the continuous exponential growth of computing without an equivalent depletion of resources.

“Chips are designed and built to be very fast, but they're very wasteful in terms of energy,” Rosini explains. “If you were to design a chip today from first principles, you would probably do it the way we’re doing. But the chip industry built this architecture 50 years ago and continued optimizing it over, and over, and over.”

At its most basic level, reversible computing aims to reduce the waste heat generated by traditional processors. When chips execute operations, the compute power needed generates waste heat – because energy cannot be created or destroyed, an input that receives two units of bit-energy uses one unit of bit-energy to perform the output and then loses the second bit-unit in the form of heat.

Where traditional semiconductors have a small number of cores that run super hot and fast, Vaire plans to build chips with a large number of ultra-efficient cores.

The difference will be so extreme, the company claims that, while in a classical chip, almost 100 percent of the energy is wasted, Vaire’s semiconductors will use almost 100 percent of the energy for compute, wasting almost nothing.

“Instead of dissipating the charge into the packaging and losing the energy through heat, it is recycled internally,” Rosini says.

This has two effects. Firstly, the chip runs cold, meaning you don't need any water to cool it, and secondly, it needs almost no energy to make it work – assuming they can pull it off.

Cornering the market

Vaire Computing is the brainchild of Rosini, a serial tech entrepreneur from Italy, and the company’s CTO Hannah Earley, who completed a PhD at the University of Cambridge in Applied Maths and Theoretical Physics. Earley has previously said that it was while studying that she became interested in “unconventional computing.”

The concept of reversible computing is not new, having been first proposed by scientists at MIT in the 1990s. However, it never took off because, at the time, there was no viable market for parallel computing. Even in more recent history, when use cases emerged, Rosini says that the accepted view on reversible computing had largely been “it doesn’t work,’ and even if it does, it’s slow.”

However, Rosini and Earley didn’t share this stance, and once the founders had become convinced of the technology’s potential, they spent three years emersed in reversible computing to make sure that before the company brought anything into the public domain, it was ready to debunk all previous criticisms.

Unlike other semiconductor technologies such as photonics, where there are hundreds or thousands of experts that startups can approach, reversible computing was such an under-researched space that, according to Rosini, there were only a handful of people globally with any knowledge or expertise.

“We all knew each other, so we just hired them,” he says. Vaire Computing now has 11 employees located in the UK and US.

Rosini says Earley is one of the world’s foremost experts in reversible computing and while at Cambridge she met Mike Frank, who built one of the original reversible computing chips at MIT. Shortly before Rosini spoke with DCD, Frank joined the company as a senior scientist.

In July 2024, Vaire announced it had raised $4 million in a seed round, bringing the total raised by the business since its inception to $4.5m. This pales in comparison to the daily spend of its well-funded competitors.

Vaire was also part of the original cohort of semiconductor startups that were selected for the UK government-backed ChipStart incubator, which helped provide organizations with access to the full Silicon Catalyst ecosystem, including design tools, IP, and prototyping capabilities. The company was also one of 10 UK-based companies selected for the Spring Cohort of Intel’s Ignite startup accelerator program.

Reversible computing is the future, maybe

Rosini says Vaire Computing was founded out of necessity. He and Earley were so completely convinced by the technology that they couldn’t believe that companies such as Intel and Nvidia were not sold on its potential.

“It was a completely open field and we just could not believe that no one else had reached the same conclusion,” Rosini says.

Rising demand for compute underpins a significant percentage of economic growth in the Western hemisphere and the AI explosion that has been witnessed over the last couple of years is only fueling that need for more processing power. However, it appears that many of the big players in the chip industry are more focused on developing hardware that can support the increasingly dense AI workloads that customers are demanding of them, rather than considering the long-term implications it could have for the world’s resources.

In the beginning, Rosini said the company did consider other architectures, studying photonics and thermodynamics, before concluding that, while they might have their benefits, reversible computing has greater potential to scale.

The decision to pursue this technology in earnest was also fueled by the company’s belief that the chip architecture that will ultimately win out is not the one that is necessarily the fastest, but the one that operates at the lowest energy point.

“We think that in about four or five years, there will have to be [an industry-wide] switch, and in ten or 15 years, every new chip that will come out of a foundry will be reversible,” argues Rosini.

He also notes that unlike in the 1990s, when Intel was able to improve single-core processor performance by about 50 percent each year, making it hard to make the case for alternative chip architectures, the industry has now reached a point where those performance gains are under two percent. Rosini believes Vaire will be able to exceed this by ten times, if not more.

Clearly not short of ambition, the company already has the next 20 years mapped out. In the short term, it plans to have its first tape out in Q1 2025, with the aim of having full-scale production up and running by 2027. Between now and then, the company intends to engage in some more aggressive fundraising to allow it to achieve the milestones it has set out for itself.

“We hold all the key patents for the technology and we have the top talent, so we're trying to get to a product before everyone else,” Rosini says. “I expect in about four or five years we’ll face a lot of competition but I think probably we might want to collaborate rather than trying to fight Nvidia and Intel.

“I mean, I'm bullish about building 60 billion chips - but going after Nvidia, I’m not so sure.”