- Siemens-led investment lifts Skeleton Technologies above a $1B valuation.
- Skeleton plans more than $200M of US scale-up and Silicon Valley R&D.
- Bloomberg reports Siemens has exclusive data centre sales rights.
Siemens has already financed Skeleton Technologies, designed its factory, and bought its supercapacitors. On October 14, the German industrial group went further, leading a nine-digit investment that, according to Skeleton, lifted its valuation above $1 billion.
Skeleton did not disclose the exact amount. Its chief executive called the round nine-digit, and the company told Bloomberg the investment exceeded $100 million.
The money will mainly fund US manufacturing and research in Silicon Valley, where Skeleton plans to spend more than $200 million on operational scale-up and research and development, working directly with hyperscalers, the cloud giants that build the largest data centres. It also plans to start cell manufacturing in the US, giving it a supply chain from individual cells to complete power systems on American soil.
“AI is scaling faster than the power infrastructure behind it,” chief executive Taavi Madiberk said in the announcement. His argument is that the limit is no longer how many GPUs, the chips that train and run AI models, a buyer can get, but how much compute it can extract from each chip and each megawatt available.
Why Siemens is doubling down
The relationship runs deep. Siemens Financial Services joined Skeleton’s €108 million round alongside Japan’s Marubeni in October 2023, and Siemens Digital Industries designed and automated the Leipzig SuperFactory that Skeleton opened on November 28, 2025, after a €220 million investment.
The new deal moves Siemens from backer to salesperson. Bloomberg reported that Siemens has secured exclusive rights to sell Skeleton’s high-power energy storage to data centre customers. Skeleton’s own announcement says only that the two companies will combine Siemens’ industrial electrical infrastructure with Skeleton’s fast-response power systems to develop and commercialise products for AI data centres.
Exclusivity cuts both ways. It gives Skeleton a route to customers that already buy power and electrical equipment from Siemens, according to Bloomberg. It also ties the company’s biggest new sales channel to a single partner. Neither company has disclosed Siemens’ stake, the length of the exclusivity, or whether it covers every region.
Siemens is also spreading its exposure to the problem. It took part in Emerald AI’s $150 million Series A, announced on August 25, which goes after the same constraint with software instead of hardware.
Who is behind Skeleton
Madiberk co-founded Skeleton with Oliver Ahlberg in 2009. The company’s Curved Graphene material underpins its supercapacitors, which charge and discharge in milliseconds, unlike regular batteries. Tech Funding News reported in November 2025 that Skeleton employed more than 300 people, and in May that it had delivered millions of supercapacitor cells to a major US hyperscaler in 2026.
The technology targets a quirk of AI hardware. GPU clusters can shift between power states in milliseconds, creating sharp load swings, peaks, and harmonics, which are distortions in the electrical current. Skeleton combines its cells with power electronics and software controls to absorb those swings close to the workload.
The International Energy Agency (IEA) expects global data centre electricity use to nearly double, from 485 terawatt-hours in 2025 to about 945 terawatt-hours by 2030, and electricity use by AI-focused data centres to triple. Skeleton’s announcement rounds the 2030 figure to 950. Data centres are on course to account for almost half of US electricity demand growth through 2030.
The International Energy Agency projects that global data-centre electricity consumption will nearly double from 485 TWh in 2025 to 950 TWh by 2030, with electricity use by AI-focused data centres expected to triple.
Rivals target the AI power bottleneck
Skeleton’s rivals attack different layers of the same problem.
San Francisco-based Verse raised a $54 million Series B on June 18, led by Bessemer Venture Partners with GV, NVIDIA, and Norrsken VC, to help data centres connect to the grid faster by managing on-site batteries and solar.
Emerald AI, which makes software that adjusts a data centre’s power use to grid conditions, raised its Series A at a $1.05 billion valuation, co-led by Energize Capital and DCVC. San Jose-based EPIC Microsystems, a semiconductor company building vertical power delivery technology for AI computing, raised a $21 million Series A led by Seligman Ventures on March 25.
A 2027 US listing would put Skeleton among European AI infrastructure companies courting American public investors. Nscale filed an S-1 with the US Securities and Exchange Commission in September, and Helsinki’s Verda reached unicorn status the same month. Public investors will want to know how much of Skeleton’s revenue depends on one sales partner, a number the announcement does not give.
The question is whether they will pay AI-infrastructure prices for a manufacturer whose newest route to market runs through Siemens.
