Fantastic Fumes and Where to Find them: Carbon Clean's attempt at a Net Zero Emissions Future

Carbon Clean 1
Artist: Roshni Kumaravel

In 2021, Google Flights launched a feature where you could see the amount of carbon emissions against the flight options. For example, an Air India flight from New Delhi to New York will result in 903kgs of carbon emissions. To offset this, you need to plant roughly 30 trees. Two round trips a year would mean 120 trees per person per year. 

Now it is obvious that planting trees for every flight you take is just not sustainable. Asking someone to “just plant more trees” is a lot like asking an asthma patient to just “breathe more”. It isn’t helpful.

So, what are we left with? One way to offset carbon emissions is to capture them at the source. This was the idea behind the first carbon capture technologies, first proposed in 1938 and implemented in 1977 at Sharon Ridge oilfield in Texas.

 For Carbon Clean’s founders - Aniruddha Sharma and Prateek Bumb – this is the moment they’ve been working towards for almost two decades. 

Aniruddha and Prateek were neighbours in a student dormitory at the Indian Institute of Technology (IIT) Kharagpur, India. In 2008, after winning a competitive summer internship at the University of Perugia, Italy, Prateek worked on an oil and gas industry-sponsored project to design a simulation model to decarbonize an oil refinery using already existing technologies. 

Aniruddha, meanwhile, spent that summer doing an internship at the University of Bern, Switzerland building a predictive statistical model of factors leading to health problems. Upon their return to their IIT dorm in the autumn of 2008, the two discussed their summer internships and recognised an opportunity. 

Consulting to Carbon Capture 

When they decided to take up the challenge, carbon capture technology was already almost 50 years old. 

“Carbon capture as a technology has been in use mostly in the oil and gas industry in the US. But we spotted an opportunity to improve the efficiency of these plants by improving the solvent that sits at the heart of the whole process. By producing a new and better solvent we were able to reduce the overall energy required in carbon capture, reduce corrosion, and therefore reduce the operating cost,” said Aniruddha.

In December 2008, they developed a business plan for this solvent and presented it at the All Pan-IIT ’08 Global Conference at IIT Madras, India, which they won. It is also where they met a Stanford professor, who advised them to go to the US.

Both Aniruddha and Prateek had exams coming up and skipping them was not an option. “In IIT, if you miss your exams, you have to repeat the semester, which ultimately will result in you graduating six months late – missing a crucial hiring window,” Aniruddha said. But they did miss the exams, much to the annoyance of the Dean. 

In February 2009 they arrived at the Cleantech Forum in San Francisco, California. Scribbling furiously in an examination hall was replaced with walks on the Stanford campus and meetings at Sandhill Road. These meetings were with attorneys, angel investors, VCs, academics, and serial entrepreneurs to help them get a sense of the global clean tech sector. They also made their first pitch and learnt an early lesson on aiming high. “People in Silicon Valley said: ‘if you have to develop the tech, how much would it cost?’ We were naïve and pre-seed level. I said $26,000 and they said, ‘come back to us when you need $60 million’. So, we didn't get the money from Silicon Valley.” 

But even then, starting up wasn’t their first choice. Aniruddha and Pratik wanted to begin their careers through the traditional route of consulting, but quickly realized that no one wanted to be consulted by 21-year-olds and those who agreed didn't want to pay.

So, in October 2009 they founded Carbon Clean, and, in the spring of 2010, Prateek graduated from IIT Kharagpur with a Master’s in engineering and Aniruddha graduated with a Master’s degree in Statistics.

Around this time, they were given access to a mothballed laboratory space at the Institute of Chemical Technology (ICT) in Mumbai, India to continue to refine their chemical solvent. By 2010, they had arrived at a patentable formulation of amines and salts called Amine-Promoted Buffer Salts (APBS), which has the potential to reduce the energy demand for the capture and regeneration process by 10-25%, reduce corrosion by 20 times, and reduce the degradation of the solvent by 10 times. 

It was also around this time that Aniruddha and Prateek first started thinking about raising an angel round and in January 2011, Blume Ventures led a $1.08m angel round anchored by $250k from Blume.

“At that point in time, Blume's fund was not even formed, but there was an idea there. We were planning to pitch to the Mumbai angels, where we met Sanjay and Karthik. In fact, we got money from Sanjay's mother. It was a kind of warehousing deal because the fund structure wasn’t ready, and it was later rolled into Blume. I think we are one of the first investments from Blume and we even pre-date Blume,” explains Aniruddha.

“Washed-up” tech

A decade later, Carbon Clean is now designing, building, financing and operating industrial carbon capture systems. Its technology operates in 49 sites across Europe, North America and Asia, capturing over 1.8 million tonnes of CO2. The company is headquartered in London, England with offices in India, Spain, and the US. 

49+ facilities and references across the globe. Source: Carbon Clean

In May 2022, Carbon Clean raised $150m in a Series C round led by US energy giant, Chevron, alongside other investors: AXA IM Alts, CEMEX Ventures, Marubeni Corporation, Samsung Ventures, Saudi Aramco Energy Ventures, TC Energy and WAVE Equity Partners.

This reflects the trajectory of the carbon capture sector in general. The large, bespoke, and hugely costly carbon capture projects that have dominated thus far are being superseded by affordable projects that build carbon capture capacity over time and combine it with other decarbonisation tools.

The new generation of standardised, fully modular, compact carbon capture units are driving this change. Skid-mounted, delivered on a truck, and installed in around eight weeks – these carbon capture units will make carbon capture accessible to many more industries than ever before.  

But how do you change a decades-old technology so that it does its job better?

Let’s talk about washing clothes.  If you have five pairs of clothes, you probably need six or seven buckets of water to wash them. You will use detergent to wash each of them, and rinse them multiple times to get them suds out. But if you do that in a washing machine, you could probably do that same job in three buckets of water. Why? Because the tub rotates. This function increases the contact between water and the fabric, and the suds move through different layers of the cloth to clean. The same concept comes into play during the rinsing function. The result is less detergent and less water requirement. The founders started thinking along similar lines to build the equipment. As the solvent rotates, it scrubs the air clean more efficiently as compared to when it would simply pass through.

This process for absorbing the CO2 from flue gas and then stripping it out of the solvent is based on the use of rotating packed beds (RPBs). Instead of contact between the flue gas and solvent taking place in a tall column, with the solvent introduced at the top and the gas at the bottom. Carbon Clean has developed an alternative means of transfer. 

Carbon Clean’s proprietary solvent is combined with a flue gas through a RPB that is contained in a drum, replacing the need for a tall column. The centrifugal force within the packing allows the solvent and flue gas to interact more efficiently, resulting in the same CO₂ capture rate in a package that is 10 times smaller than the existing column design.

After the CO₂ is captured from the flue gas, it is removed from the solvent in a regenerator. The solvent can then be re-used and the captured CO₂ is then further processed for utilisation in value-added products or transported to permanent storage sites.

Of particular interest to the company’s investors and the wider market, is Carbon Clean’s breakthrough technology, CycloneCC. It solves the two biggest barriers to the widespread deployment of carbon capture – cost and space. CycloneCC is a fully modular, prefabricated and skid-mounted carbon capture solution that reduces the overall cost of carbon capture by up to 50% and has a physical footprint that is up to 50% smaller than conventional carbon capture units.

A young team in a young industry

“People did not take them seriously because there were no grey hairs in the organization. Because of capital constraints, our offices were also fairly modest. So, we were always up against that perception that the organization is so small, why should anyone invest crores in it?,” said Rohan Paranjpe, an early employee at Carbon Clean.

Getting sales was another challenge. Reaching the right person in a major industrial company was tough, and it was additionally hard to convince an experienced 50-year-old who’s been doing this for 30 years of their life, as a 20-year-old. Even if a meeting was secured, there was little progress thereafter.

“We were dealing with constant rejection, especially in India. Instead of being proud that a solution was coming out of India, potential clients were instead looking for solutions from overseas,” said Aniruddha. 

In one of the earliest major breakthroughs, Carbon Clean got validation from Dr. Avinash Patkar, head of sustainability at Tata Power, who had spent more than four decades in the field of carbon capture. 

“Karthik met Dr. Patkar in early 2011 and he confirmed that Carbon Clean’s solvent will be a game changer. At that time, we were a non-classical portfolio company, but we were the only one of its kind in India and Tata Power was saying it’ll work, so that really helped us,” Aniruddha said. 

Another intervention that was to prove crucial in the history of Carbon Clean happened in April 2012. Aniruddha and Prateek met a UK government scout in Mumbai who was looking for new technologies that could apply for UK government funding. Between 15 April and 29 April, Aniruddha - on his first visit ever to the UK - put together a consortium of six industrial partners, and three UK universities (Imperial, Leeds, and Sheffield) to apply for a UK government grant valued collectively at $6.6m. The success of this grant application led to the company moving to the UK and a new beginning for Carbon Clean.

“It’s not unfair for VCs to stay away from these areas because they feel this is going to take way too long, and they don’t know how the company will survive and scale until then. The Carbon Clean story reminds me of something I read in a venture capital book by Sebastian Mallaby called ‘Manufactured Serendipity’. In fact, if I write my first book it will be titled ‘Manufacturing Serendipity’, because that’s basically a VC’s job. What happened here was if Carbon Clean had stayed in India, focusing on decarbonising Indian corporates, we would either be dead or we would be in the same position even today,” said Karthik. 

What’s next

In February 2022, Intergovernmental Panel on Climate Change, a United Nations body, released a 3500-page report that suggested that humanity had “a brief and rapidly closing window” to mitigate the effect of global emissions and avoid “dangerous and widespread disruption.” The window? Three years. 

The ‘energy trilemma’ – the need to deliver energy security and affordability, while also transitioning to net zero – is front of mind for many nations. Carbon capture has a key role to play in meeting these objectives.

Heavy industries are the worst defaulters when it comes to emissions. Industrial carbon emissions account for about 30% of global emissions. If we are at 50 billion tons of carbon emissions today, about 15 come from industrial emissions.

But as they say, it is not the healthy who need a doctor, but the sick.

Hard-to-abate industries, such as steel, cement and refineries, are embracing carbon capture as their best current option to reduce their emissions. The Global CCS Institute’s Global Status of CCS 2022 Report has noted a 44% increase in carbon capture and storage (CCS) projects over the past 12 months and the capture capacity of all CCS facilities under development has grown to 244 Mtpa. In 2022, there were 30 CCS projects in operation, 11 under construction and 153 in development. In addition, 21 countries have already included CCS in their Nationally Determined Contributions (NDCs).

Carbon Clean is scaling rapidly to meet this challenge and Aniruddha is excited to be working with some historically large emitters, such as lead investor Chevron. “They are among those most eager to address the climate challenge.

Looking back to the start, both were already sensitive to the issue of global warming and its effect on India. Aniruddha, who was born and raised in Bhopal, India, the site of the world’s worst industrial accident in 1984, had joined the Indian Youth Climate Network upon entering the university and spent the next three years participating in climate change protests and writing student policy papers on global warming for submission to the Indian government. Prateek had grown up in Jaipur, India where summer temperatures had been steadily rising and had reached 550C (1310F) threatening an impending humanitarian crisis. 

From discussions with global CEOs, industry experts, investors and policymakers at Carbon Clean’s COP27 Forum, it’s clear that there is a huge demand for carbon capture and Carbon Clean stands ready to meet this demand.

For Aniruddha and Prateek, it’s been an incredible journey. In addition to the $150 Series C round, 2022 saw the start of a project for NTPC back in India and projects with Chevron in the US and CEMEX in Germany. It also saw the company double in size to reach 100 employees. In 2023, its technology will be operating in over 50 sites worldwide and will have captured well over 1.8m tonnes of CO2. Not bad for two dorm-buddies from IIT.


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    Disha Sharma

    Disha is tasked with building compelling narratives for Blume. Prior to this role, she was a journalist with Economic Times, where she extensively wrote on food tech, gaming, and consumer tech. She has also worked with LinkedIn,…
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