Connect with us

Hi, what are you looking for?



Decarbonizing Cement With AI: An Interview With alcemy Founder Leopold Spenner

What’s the story behind alcemy, and how did you arrive at the current product offering?

Rob built the dynamic pricing pipeline for Flixbus (that autonomously controls >100,000 ticket fares a day), and I had spent most of my life working around CO2 reduction of cement and concrete. When we met at the second Entrepreneur First cohort in Berlin, it immediately clicked: I knew that the less CO2 concrete has, the more important autonomous control becomes.

How would you describe the problems in cement, and which of those can be solved with alcemy?

Cement, and later concrete, are made out of natural materials, so it is inherently challenging to produce it with consistent quality. Even more because one has to wait an entire month for the most important quality test result. Quality and production management is extremely manual and therefore imprecise — the resulting concrete has a high margin of error. This is a major roadblock for producing low-carbon concrete at scale (the construction material is responsible for 8% of worldwide CO2). Our predictive production control system removes this roadblock by increasing precision and transparency.

Where will you be 5 years, and where will you be in 10 years?

5 years: Low-carbon concrete has become the standard in the EU and alcemy’s technology is steering the production of every single cubic meter.

10 years: alcemy has made ready-mixed concrete so easy that the developing world starts adopting it to industrialize their concrete production, so that we have helped reduce 1 Gigaton of CO2.

In your view, what other tech needs to develop to make the building process less carbon intensive?

Speaking about the entire building process, much more focus should be spent on repurposing old buildings instead of building completely new (happens often in Germany for single-homes in the outskirts of cities while the city centers are abandoned). Secondly, I believe regulation that favors eco-friendly tenders of GCs will have a far greater impact than any technology.

Speaking about cement, it will be a combination of new natural input materials (e.g., clay), better quality control (with alcemy) and for the last 10-20% potentially carbon capture and reuse at a handful of Giga-Clinkerplants Europe-wide.

What cleantech companies and organizations inspire you, and why?

Definitely the efforts of Bill Gates and how he throws light on the huge CO2 emissions from making things like steel, cement and plastic.

What are currently the biggest challenges for alcemy?

  1. Finding product-market fit and a viable business model: the supply chain is very complex and carries lots of legacy — finding our sweet spot that makes a difference, helps save CO2 and proves to be a viable business is a big challenge.
  2. Developing the technology is challenging because we deal with real-time data that tends to be messy and need to steer production based on this — 24/7 and carrying high responsibility.
  3. Hiring a diverse team — even though this was one of our key priorities, we are now 16 FTEs with only 4 females and 2 non-German-natives. We felt like efforts to get diverse talent into a pipeline that is already relatively empty makes it 10x harder and in our stage we did not have the capacity to handle this.

Is there a particular company (organization) you wish you could work together with? Maybe someone is reading this and can help make the connection.

Architects like Rem Koolhaas (OMA), Herzog & De Mauron, or Foster + Partners

If you look at all your entrepreneurial activities, what do you wish you had known, or what mistakes would you try to avoid going into the future?

I would try to avoid being too frugal, i.e., very conservative hiring roadmaps, and too critical with ourselves, i.e., not celebrating achievements along the way appropriately.

Are you interested and excited to get into a region like China or the US early with Alcemy? Is this realistic?

Not this early. We are a deep-tech company and have perfect conditions to develop our technology here in Europe (cement/concrete R&D happens predominantly in Europe // cluster of innovative large and SME producers, suppliers, universities and associations // CO2 imperative since 2005 through EU-ETS // strong and experienced talent). In 5-7 years down the line, an expansion to US and China is planned.

What do you wish politicians would understand, and which law would you enact if you could?

That public construction procurement should lead the way by incorporating CO2 into their tender criteria.

What are the most underrated or underappreciated big trends in cleantech and society?

  1. Many people in my generation want to make an impact on halting global warming, usually with personal sacrifice (e.g. not flying, turning vegetarian, etc.). But this does not scale, and cement is a good example for this: 90% of cement is consumed in the developing world that still has lots of infrastructure to build — and sacrifice is not a solution these countries will accept. What IMHO is overlooked is that individuals from my generation in Europe can make a huge impact that goes far beyond personal sacrifice — when working on technical innovations in carbon-intensive industries: just like cement. Employees at alcemy can help save more CO2 than the entire flight sector emits — and since so few people work on cement, chances are high each and every individual will make a measurable impact.
  2. Industries that make things (steel, cement, plastic, aluminium, glass, paper, etc.) are not prominent in discussions around global warming — despite being system-critical, hardest to decarbonize and responsible for ~20% of worldwide CO2 emissions. Decarbonizing them requires huge amounts of electricity (optimally renewable, i.e. more wind mills and solar cells) and infrastructure (electricity grids, hydrogen grids, industrial railway grids, etc.) — but expansion is extremely slow in Germany due to e.g. strong objection rights for individuals and associations — making net-zero in 2045 a dream rather than a potential reality.

Images courtesy alcemy

Sign up for daily news updates from CleanTechnica on email. Or follow us on Google News!

Have a tip for CleanTechnica, want to advertise, or want to suggest a guest for our CleanTech Talk podcast? Contact us here.

Electrifying Industrial Heat for Steel, Cement, & More

I don't like paywalls. You don't like paywalls. Who likes paywalls? Here at CleanTechnica, we implemented a limited paywall for a while, but it always felt wrong — and it was always tough to decide what we should put behind there. In theory, your most exclusive and best content goes behind a paywall. But then fewer people read it! We just don't like paywalls, and so we've decided to ditch ours. Unfortunately, the media business is still a tough, cut-throat business with tiny margins. It's a never-ending Olympic challenge to stay above water or even perhaps — gasp — grow. So ...
If you like what we do and want to support us, please chip in a bit monthly via PayPal or Patreon to help our team do what we do! Thank you!
Written By

I'm investing in positive companies and am passionate about climate action and long-term human challenges. Early partner at BEAM (United People of Climate Action) and CleanTechnica (#1 cleantech-focused new & analysis website in the world), among others.


You May Also Like


There has been a lot of concern about battery materials and global geopolitical risks. In some ways, it would be easy to just keep...

Autonomous Vehicles

The danger of artificial intelligence is a common theme in science fiction because it allows authors and filmmakers to explore ethical and societal questions...

Autonomous Vehicles

One of Tesla’s main contributions to the world, besides popularizing the electric vehicle, includes its huge leaps and bounds in the artificial intelligence sector....


Researchers at MIT are discovering new ways of making concrete that will release less carbon dioxide in the atmosphere.

Copyright © 2023 CleanTechnica. The content produced by this site is for entertainment purposes only. Opinions and comments published on this site may not be sanctioned by and do not necessarily represent the views of CleanTechnica, its owners, sponsors, affiliates, or subsidiaries.