Tough Tech Summit — 2023

Aryan Saha
5 min readOct 9, 2023

This past weekend, I had the opportunity to attend The Engine’s Tough Tech Summit, where I, along with science-focused VCs and hard-tech founders, discussed, questioned, and debated how to build and grow companies to solve science-based problems.

Tough Tech Summit was definitely one of the top conferences I’ve attended in my life. The Engine, MIT’s VC fund dedicated to incubating and growing lab spin-outs into profitable, effective, and purpose-driven companies impacting millions. In addition to this, The Engine focuses on companies tackling the greatest and grandest of scientific problems: nuclear fusion, drug delivery, solid refrigerants, 0-carbon cement, hydrogen fuel, carbon capture, catalysts, quantum computing, biomanufacturing plant-based products, decarbonizing chemicals, wave drilling for geothermal, and more.

The Engine organized Tough Tech Summit into two days: one for investors, and one for builders. On invest day, VC partners and potential investors in companies came to watch these companies pitch their product for potential fundraising, along with listening to hard-tech VC leaders like David Fialkow, ex-CTO of Meta and current Managing Director at General Catalyst, and Katie Rae, CEO of The Engine. In main stage talks, there was definitely a sentiment certain VC-partners wanted to vouch for amongst other VCs. During the keynote speech on Invest day, David Fialkow re-itereated, numerous times, how the current cycle of VC attention and hope in climate-tech companies was the most confident and definite. Nearly a decade after the primary “cleantech boom and bust” around 2010s which fell after a record $44.5 billionwent into the sector, Fialkow wanted to emphasize how definite the applicability and demand was for cleantech, as well as how ventures should hedge all bets into companies tackling hard-tech. Speaking to various VC funds and consulting firms, the sentiment was matched. VC partners have been raising new venture funds focused on clean tech investment; consulting firms have been scouting clients within clean tech, as well as joining investment rounds for several of these companies.

A quick scan of the VC/investing atmosphere of the past few months supports what I learned during conversations and keynote speeches. Lowercarbon, Chris Sacca’s climate-focused VC fund, recently raised a whopping $550 million to invest in more companies. VC funding as a whole has also increased consistently:

Between the two days, Build day was by the most beneficial and engaging day for me. Compared to invest day, I was surrounded by founders throughout the day, getting into conversations with CEOs of series C companies, along with companies raising their seed round after just spinning out of their university laboratory.

Fireside Chat:

Build day started off with Katie Rae’s fireside chat with Bob Mumgaard, CEO of Commonwealth Fusion Systems, a company utilizing high-temperature superconducting magnets to create smaller tokamak nuclear fusion systems. Mumgaard spoke at depth on the struggles with growing CFS, as well as how he, as a CEO in a pioneering hard-tech company, orients his mindset for his company’s success.

In regards to his company, Mumgaard explained how the origin of CFS was in response to the question: what vehicle makes the most sense to acheive clean, widespread, and accessible nuclear fusion energy? CFS was founded as the response to how to best and most rapidly construct and implement this technology. Along with this initial vision of CFS, Mumgaard elaborated on how he needed to think ahead of time of the company’s potential roadmap, but also how important it is to get insights from the right person during each stage of growth. Early rounds required technical and cost-minimization strategies, whilst later stages require attention towards pathways to commercialization and distribution.

Unconference Sessions:

Tough Tech’s signature event, “unconference sessions,” let around 10–15 participants sit in a roundtable discussion with the co-founders of their portfolio companies. In one of these sessions, I was able to ask and participate in an intimate Q/A session with the CEO and COO of Lilac Solutions.


Lilac Solutions, founded by Dave Snydacker, Nick Goldberg, Tom Wilson, tackles issues related with Lithium-ion mining. With the world going towards electrification, demand for lithium has increased exponentially with the IEA expecting a 40x increase in demand by 2040. The status quo for lithium extraction involves the usage of brines, where a salt-water mixture with lithium is pumped to evaporation fields at the surface. Over the course of several months (up to 2 years), the saltwater evaporates and leaves unpurified Lithium Chloride mixture which is then purified in a facility. This entire process demands months of time, as well as high energy usage. When brine enters the evaporation ponds, it needs to be heated from “10 to 80 degrees celsius increased the Li+ adsorption efficiency from 15% [to]( are pumped from underground,of Na2CO3.) 70%.” Typical natural gas usage for lithium brine evaporation processes emit over 790 gCO2 per kilogram. At the end of the process, only 40% of the feedstock lithium is recovered for puification and usage.

Lilac Solutions uses a patented ion-exchange technology to decrease GHG emissions, decrease time to commercialization, decrease land usage, and increase lithium extraction methods. Lilac’s process extracts brine into tanks containing their engineered “bead”, the core technology of their process. The materials within this beads allow for percolation of lithium into the beads, which is the process of a mineral being able to enter and filter within a material. After the beads absorb the lithium-ions, hydrochloric acid is used to “flush out the lithium, yielding lithium chloride.” This lithium chloride then becomes processed using conventional methods.

Lilac Solutions raised a $150 million series B in 2021. During the unconference session, I was able to listen and ask questions to David Snydacker, CEO, and Raef Sully, COO.

After hearing numerous pitches from hard-tech companies, I was surprised by how discrete technological advances seemed to be for these companies. David Raef elaborated on the months long process it took to develop Lilac’s key solution — in fact, David narrated how he used material modeling software to create the beads in theory after he graduated with his PhD. However, after they’ve patented the process, neither leader is leading to any engineering or scientific updates to their product. Rather, they’re focusing on commercializing and achieving revenue through licensing and implementing their technology in different projects throughout the world. Hard-tech demand a level of breakthrough to make a considerable improvement in the product, which seems to explain the discrete movement in product R&D.

Special thanks to the team at The Engine for hosting the summit, along with Michael Raspuzzi, Zayn Patel, Christina Wang, Alice Liu, Anant K, Sanket Deshpande, Adam Slavney, Carlos Araque, and others for making my experience rich with new lessons and learnings.