Airthium Founder Andrei Klochko on Replacing Fossil Fuel

We are building a technical solution to make it cheaper not to pollute at scale and prevent 33% of worldwide CO2 emissions cost-effectively. We build heat engines of a new kind that convert electricity to heat and heat to electricity with record efficiency, low cost, very low maintenance, and zero carbon emissions. In the near term, those engines will be used to provide low-cost, zero-carbon steam and hot air for industries (like paper manufacturing and food processing) and in the long term, to provide cost-effective seasonal energy storage. Seasonal energy storage is what is needed to replace coal and gas-fired power plants by 100% renewables and make electricity cheaper for customers in the process.

We are two co-founders plus 10 employees. I started Airthium right after my PhD to find a cost-effective solution to the problem of energy storage. Then Franck joined me a few months later. He found me because he just came back from one year traveling around the world and was shocked by the magnitude of what pollution had done to our environment everywhere he went. Fast forward to the present day and we have six PhDs on the team, are developing decarbonized industrial heat and seasonal energy storage, and are about to move to our own industrial space.

There are three levels of competition, both for industrial heat and energy storage.

The first level is business as usual — to keep burning fossil fuels. Net zero pledges from companies, consumer perception, and future CO2 regulations are in our favor. Once we are fully industrialized, we also expect to be cheaper than fossil fuels in many geographies.

The second level is alternative, clean industrial heat (concentrated solar, biofuels, resistive heating) and backup electric power sources (flow batteries and hydrogen storage, either hydrogen gas storage in salt caverns or cryogenic liquid in above-ground storage at negative 253 degrees Celsius). We are cheaper than all of those — except for salt caverns, which are severely geographically restricted.

The third level is similar high-performance heat engines (Brayton cycles like Malta Inc. and ENDURING from NREL, other Stirling engines like Olvondo Technology and Azelio, and ammonia-fired piston engines). We are the only reversible heat engine that can burn ammonia, store electricity as heat on a single powertrain, and have high efficiency and low cost. Eventually, based on all our forward-looking assumptions regarding how the industry and grid will evolve, we get (on paper) the lowest total cost of clean heat and reliable renewable electricity.

The big problem with climate change is cost. It is simply cheaper to pollute. We plan to reverse this trend to make clean power cheaper than fossil fuels. Our plan is two steps: First, we tackle industrial heat as a beachhead market and then seasonal energy storage as a long-term market.

Regarding industrial heat, heat pumps make more heat with the same amount of electricity by harvesting heat from a “free” waste heat source in the process (like hot water generated when cooling down industrial machines). By making heat pumps available in the 200 to 550 degrees Celsius market segment, we allow this segment to replace polluting gas burners with clean heat pumps in a cost-effective way. This makes electric industrial heat more efficient, and hence cheaper in many geographies, than fossil-fired heat.

This first market can remove 3% of worldwide CO2 emissions, and there are no established high-temperature heat pump competitors in our segment.

Regarding backup power, today the cheapest alternative is natural-gas-fired peaker plants. Lithium-ion batteries can replace peaker plants most of the year but not all year long. Relying on lithium ion only will lead to blackouts when solar and wind die for weeks at a time (this happens every year in most geographies). By combining short-duration pumped heat energy storage in molten salt or sand and seasonal storage in ammonia into a single system relying on just one engine (our Stirling engine), we replace lithium ion and peaker plants with a combined, mutualized, cheaper alternative.

Since solar and wind are on their way toward becoming the cheapest power sources in almost all geographies, using our system this way can cost-effectively replace all fossil-fired power generation, which is responsible for 30% of worldwide direct CO2 emissions.

This is how we plan to prevent 33% of worldwide direct CO2 emissions, and the associated global warming, in a cost-effective way.

First, we have built and tested an instrumented, pressurized, cold compression head prototype of our highly efficient Stirling engine. The experimental results so far confirm our models, and we are about to test full Stirling engine operation before the end of this year. Next year, we plan to begin preliminary testing on the first version of our engine, capable of 550 degrees Celsius operation.

Furthermore, over the last 12 months, we scaled our team from five to 12 full-time employees and recruited a chief technology officer with a PhD in fluid mechanics from École Polytechnique and two years of postdoctoral experience from École Polytechnique Fédérale de Lausanne. By the end of this year, we plan to move into a 13,000-square-foot dedicated industrial lab and office space to be able to build and test our next machines up to the 100-kilowatt heat pump demonstrator.

Also, in February 2022, we found a way to bypass the last major technical roadblock we had on our development road map. This breakthrough allowed us to access the industrial heat pump market, which we couldn’t access before because of feasibility reasons.

Finally, we have made inroads with potential industrial customers of our high-temperature heat pump in the food, paper, and automotive industries.

After this raise, the overall goal is to reach the demonstrator stage, with at least one 100-kilowatt heat pump demonstrator built, several patents filed, several pilot deals and manufacturing/maintenance partnerships significantly underway, and a much finer knowledge of our techno-economics, industrial manufacturing and supply chain, quality control, total cost of ownership, and actual market subsegments. To achieve this, we will execute several steps:

1. We will proceed with the move to our industrial lab and office space and buy several pieces of heavy machinery to significantly accelerate our prototyping capabilities and speed. This is essential in holding our timeline.
2. We have a hiring plan in place to help us perform all of the tasks listed above, including both technical and non-technical roles.
3. With those three assets (extended team, location, and equipment), we will iterate on our prototypes until stable, reliable, and efficient operation of our engine is achieved and then scale our engine and adapt it to the first use cases to reach the demonstrator stage.

Go-to-market is essential, especially so for capital-intensive hardware startups. 

We plan to start with small-scale (200 kilowatts to one megawatt thermal) retrofits of industrial facilities that use steam and hot air by keeping existing gas-fired boilers and dryers as backup sources and providing our heat pump to cut on energy costs while reducing CO2 emissions.

We then plan to scale our heat pump business up to 20-megawatt thermal units by relying on partners for assembly into a boiler or dryer product, commissioning, and maintenance.

Then, once the market is ripe, we plan to provide our engine to developers who will build the first seasonal energy storage demonstrators. In doing so, we will tap into all the reliability and manufacturing experience of the Stirling engine, accumulated during the scaling of the heat pump business.

Finally, we plan to scale the seasonal energy storage business, building ever bigger engines and letting developers commission gigawatts of them alongside the huge solar and wind farms of the future. During this phase, we plan to keep a direct connection to the end user by providing the control and predictive maintenance software that will run on all engines.