sam altman-backed exowatt wants to power ai data centers with billions of hot rocks

Addressing the AI Power Challenge: Exowatt's Innovative Approach

Hannan Happi, while contemplating solutions to the escalating energy demands of artificial intelligence, centered his efforts around a specific benchmark: a cost of one cent per kilowatt-hour.

“Numerous configurations and designs were thoroughly investigated,” Happi, the co-founder and CEO of Exowatt, explained to TechCrunch. “Each iteration presented a unique framework. Our focus was consistently on learning from each design: how to minimize structural expenses, how to curtail maintenance costs, and how to achieve optimal performance.”

Introducing the P3 Unit

Following extensive research and development, Exowatt’s initial step toward realizing this objective is a compact unit, approximately the size of a standard shipping container, and features a transparent canopy. The internal design mirrors this simplicity.

If Exowatt successfully delivers on its commitment to provide affordable solar energy with 24/7 electricity generation, it has the potential to revolutionize the data center industry and the broader energy sector, offering continuous power at a remarkably low cost.

Securing Funding for Rapid Expansion

To accelerate production and achieve the one-cent per kWh target, Exowatt has secured an additional $50 million in funding, extending its $70 million Series A round which concluded in April, as exclusively reported by TechCrunch.

MVP Ventures and 8090 Industries spearheaded the extension, with contributions from Atomic, BAM, Bay Bridge Ventures, DeepWork Capital, Dragon Global, the Florida Opportunity Fund, Massive VC, New Atlas Capital, Overmatch, Protagonist, and StepStone. Andreessen Horowitz and Sam Altman were among the previous investors.

Happi stated that Exowatt had not initially planned to seek further capital following the April funding round, but “the considerable momentum observed in the market” and “significant investor interest” prompted the decision to accept the new investment at an increased valuation.

Current Backlog and Production Goals

Exowatt currently has a backlog of approximately 10 million P3 units, representing a capacity of 90 gigawatt-hours. “Our priority is to scale production as quickly as possible, moving towards millions and ultimately billions of units,” Happi affirmed.

The company anticipates reaching its one-cent target when annual production reaches around 1 million units, according to Happi.

Leveraging Established Technology

Exowatt is effectively refining a technology that has existed for decades. Known as concentrated solar power or thermal solar power, it harnesses solar energy to heat materials adept at storing or transferring thermal energy.

When thermal energy is stored for prolonged periods, these materials often resemble or are derived from rocks – leading to the technology’s nickname, “rocks in a box.”

How the P3 Device Works

Each P3 device comprises a metal enclosure topped with lenses that concentrate sunlight into a focused beam. This beam heats a specialized brick within the container.

A fan circulates air over the brick, transferring the heat to another unit containing a Stirling engine – a piston-driven device converting heat into mechanical energy – and a generator. Increasing power storage involves installing additional P3 units.

“The entire system is engineered for extreme simplicity,” Happi emphasized.

Each thermal battery can retain heat for up to five days, ensuring uninterrupted operation. Exowatt connects multiple batteries to power a single generator, with the number determined by the customer’s desired electricity output and speed of generation.

The system’s efficiency is comparable to photovoltaic solar panels and slightly surpasses that of PV systems coupled with lithium-ion batteries, Happi noted.

Addressing Past Challenges and Future Potential

While other companies have explored similar technologies, many have struggled to compete with the declining costs of photovoltaic solar and lithium-ion batteries.

Happi contends that the P3’s compact size and Exowatt’s iterative development process distinguish it from competitors. He highlighted that there are just over 100 solar thermal or concentrated solar power projects globally, compared to the 1.5 billion solar panels produced annually.

“This disparity in production volume significantly impacts the learning curve,” he explained.

“Exowatt’s core strategy revolves around scaling the manufacturing of a modular system that has demonstrated its functionality in principle, and capitalizing on the manufacturing learning curves.”

Limitations and Opportunities

Exowatt’s cost-effectiveness may vary depending on location, and powering a data center could necessitate substantial land usage. Furthermore, the system performs optimally in regions with abundant sunshine, potentially limiting its widespread applicability.

However, Happi countered that there is a “significant correlation” between areas where Exowatt’s P3 excels and locations where new data centers are being constructed. “We are not lacking in potential projects,” he stated.