NASHVILLE SERIAL tech entrepreneur Martin Renkis was recently named CEO of Corenix, a company created by Submer Inc., which is based in Barcelona, Spain, with regional headquarters in Houston and Taipei. 

The announcement came this week amid white-hot interest in data-center development, modular-compute buildouts, related infrastructure, and the critical role of liquid-cooling engineering.

While privately-held Submer is a "full-stack AI infrastructure company," spin-up Corenix is "a modular data center infrastructure company serving neoclouds, hyperscalers, and AI operators," according to Submer's press release earlier this week.  

Eleven years after Submer's founding in Spain, the Submer brand has gained considerable attention within "sustainable IT infrastructure" markets of both Europe and North America.

Submer companies' current flagship offering is SmartPod, which supports immersion cooling of compute assets.

A few months ago, Renkis was interviewed during the Pacific Telecommunications Council's PTC 26 conference, where he told conferees power generation and cooling can no longer be treated as separate conversations.

He also told his audience many data-center operators are turning to on-site generation of compute power in order to overcome grid constraints and to reduce loss of energy lost as heat. He added that in high-denisty AI environments energy "waste represents both a cost burden and a missed opportunity," thus making "holistic energy design" and integration of generation and cooling strategies essential.

Renkis-led Corenix is aligned with two other Submer companies: Rubix Data Centers, which is a London-based Submer startup that develops and operates AI data center campuses; and, recently acquired Radian Arc, an infrastructure as a service for running sovereign, teleco-focused GPU cloud services.

In July, Submer announced it would invest what is today the equivalent of about $1.13BN to develop an AI data center operated by Rubix in Catalonia, an autonomous region of Spain.

Submer was co-founded in Spain in 2015 by brothers-in-law Pol Valls Soler and Daniel Esteve Pope, who VNC research indicates serve respectively as chairman/CEO, and as secretary/director and CIO. Submer Group Companies has been led three years by Patrick Smets.

The early advance of Submer's SmartPod and related offerings during 2018-22 was partly driven by grants via a European Innovation Council (EIC) program.

Submer investors have thus far included M&G Investments (London), Norrsken VC, Tim Reynolds (erstwhile cofounder of Jane Street Capital), Mundi Ventures, Planet First Partners, Big Sur Capital and others. 

Notably, the objectives of abovementioned investors M&G, Norrsken, Planet and others have been characterized by the EIC as aligned with the European Green Deal-linked taxonomy or classification framework, which undergirds efforts to guide investment toward sustainable projects and activities. 

VNC has found no explicit references to plans for a Submer IPO or other liquidity-exit events. We did notice that Big Sur Capital's portfolio page said the firm had made a partial exit from Submer. Morgan Stanley's EquityZen and other platforms do offer investors a potential path toward aftermarket trades. 

VNC research indicates Submer's first fundraising was in 2018 for a Seed raise in 2018. Research indicates it has raised north of $130MM since its founding. Prior to forming Submer Inc., the cofounders operated a data-center business. Submer is strongly allied with Madrid-based Telefonica.

Submer Inc. was registered in Delaware in 2019. Submer Inc.'s Submer Group Companies Inc. was registered earlier this month in Delaware. Corenix Corp was registered in Delaware about five months ago. Submer's regional headquarters, manufacturing and other sites are mapped here.

RENKIS TRAJECTORY

Prior to joining Corenix, Renkis served more than eight years with Johnson Controls, which has a large operational presence in Milwaukee and headquarters in Cork, Ireland. 

At Johnson Controls, he was ultimately executive director for data center infrastructure. His duties spanned strategic partnerships related to such things as AI, fuel cells, and asset tokenization. Related.

Between 1992 and 2018, Renkis founded and successfully exited at least two of his own startup ventures:

• Smartvue Corporation, a "commercial physical security SaaS cloud platform" that was acquired by Johnson Controls (NYSE:JCI). Earlier VNC coverage of Smartvue here. As VNC reported in 2008, very early SmartVue investors included Crom Carmichael, Mike Shmerling and others. SEC history. Renkis last year told VNC that Fortress Investment Bank was key to its later-stage financings. Over time, Smartvue had attracted interest from potential bidders, market headwinds had risen, and debt pressures had mounted. The sale to Johnson Controls completed that chapter of his career. More on the Smartvue board in this 2015 Nashville Post story . Also, see Renkis's comments during this "Your Seat at the Table" podcast via YouTube.

• Trainersoft Corporation, which he started while based in North Carolina. It offered a corporate e-learning platform, and was acquired in 2002 by then-Boston-based Outstart. Outstart later sold to Kenexa, which was then absorbed by what is now IBM Kenexa Learn).

According to his July 2025 LinkedIn-Pulse post and a related 2024 U.S. PTO trademark filing, Renkis remains the founder of AlphaTag Corporation, which is a dba for Tagii Inc. 

Renkis told VNC in 2025 that Alphatag was an Internet of Things (IoT) play, involving near-field communications (NFC) devices and blockchain. 

VNC research this week found an Alphatag application associated with selling gift-package tags that gift recipients can use to trigger video or audio greetings from giftgivers. An Alphatag promo clip is branded "Modern Gifts," which research suggests may have been registered as early as 2020. Alphatag pairs with Stripe for payments and apparently asset-management activities -- including finding lost golf clubs that have been properly tagged.

Last December, Renkis appeared on the Data Center Go-to-Market Podcast, during which he discussed his personal experience in the Data Center sectors, as well as the fine points of Data Center Cooling as a Service.

For example, according to his LinkedIn profile, he remains an entrepreneurship mentor at both Vanderbilt University's Wond'ry innovation center and the Nashville Entrepreneur Center (NEC). Years earlier, Smartvue was a finalist for the NEC's "Gamechanger" award.

Renkis often notes his success in registering 80 or more U.S. utility patents, and VNC easily found dozens of them online, with many seemingly part of Smartvue's legacy.

A native of Erie, Pa., his earlier experience included serving as executive chairman of Thermoclad Company, which was founded by his father, Alan Renkis, who had run the company more than 50 years and had immigrated to the U.S. after World War II from the Republic of Latvia, in the Baltic region of northern Europe. His family eventually sold Thermoclad to the Protech/Oxyplast Group (now The Protech Group, based in Quebec and in Ghent, Belgium).

Renkis previously explained to VNC that while leading Thermoclad he visited Nashville on a sales mission. That's when he experienced his first "meat and three" diner. 

That's also when, during a chance encounter with a Nashville executive in the former Merchants restaurant on Nashville's Lower Broadway, he was provided an intro that led him to develop and license interactive-learning software, for which he maintained IP rights that helped start the aforementioned Trainersoft.

Copilot

Years later, after marrying Laura Williams Renkis (now a luxury-travel advisor), the couple relocated to her homestate of North Carolina, but returned to Nashville in 2002.

Renkis, now 64 and father of two adult children, resides in Davidson County.

He graduated from Denison University in Granville, Ohio, bearing a bachelor of arts degree spanning arts, economics and cinema.

During 2020-24, he also joined several Stanford University programs focused on technology leadership, AI concepts and applications, energy innovation, and the economics of energy transition. 

After a few post-collegiate years experimenting in film, video and software, he moved into digital video security and software innovation, and ultimately into broader tech entrepreneurship.

Renkis has not yet responded to our request for an update interview. We'll update this story, as warranted. VNC

.last edited 1531 30 September 2026