Why I founded “out of the blue”

Lennart Joos
8 min readFeb 19, 2021


In September 2020, I founded out of the blue, a start-up with a mission to remove CO2 from the ocean in a safe, cost-effective and large-scale manner. Out of the blue is developing and scaling a novel process for CO2 removal from sea water, in order to fight two of the biggest problems of our time: ocean acidification and climate change.

Wait… but… why?

Why do I want to do that? Why do I keep on pushing this idea so hard? Why did I start this journey in the first place? Why was that so important for me? And why is it important for you and everyone else?

In three parts, I will cover the “why” behind out of the blue. In this piece, I want to illustrate why I decided to launch out of the blue in the first place. The next article will dive into what I believe is the right format to do this. And in the last part, I will discuss what is missing in existing approaches. If you have any questions, please connect and engage.

So: why!?

1. Removing already emitted CO2 is necessary

Since the start of the industrial revolution, more than 2000 billion tonnes of CO2 have been emitted. Every year, 40 billion tonnes are added on top of that. Even under extremely optimistic scenarios for the energy shift towards renewable sources, cutting down 7% of CO2 emissions every single year (that is more than an additional global epidemic every single year), we probably won’t manage to remain within the budget for 1.5- or 2-degrees global warming — which boils down to: “hell on earth”.

First and foremost, we need to decarbonize (i.e. get rid of fossil fuels) rapidly and massively, but we need to do more!

That “more” is CO2 removal: some of the already emitted CO2 will need to be removed from the environment again. This approach can help to buffer some of the CO2 overshoot, as well as access and rewind historical emissions. Moreover, it can somewhat stretch the lifetime of technologies that might keep relying on fossil fuels in the near future. Think about aviation: while electric planes exist, and will be used for short distances, it is highly unlikely that you’ll fly electric from London to New York any time soon.

I also want to stress that CO2 removal is not a “get out of jail free” card. This is not a silver bullet that allows us to continue unsustainable activities. The world needs to quit its addiction for fossil fuels, which means rethinking mobility, rethinking residential heating, rethinking consumption of food and electronics alike. In fact, CO2 removal only makes sense when all of the above is being taken care of. Otherwise, it’s like trying to empty the ocean with a thimble (or, as they say in my native Dutch: “dweilen met de kraan open” — “mobbing with an open tap” — you first REALLY need to close the tap).

Photo courtesy of Peter Buschmann, United States Forest Service, USDA. Some additional editing by W.carter., Public domain, via Wikimedia Commons

2. Isn’t planting trees enough?

One of the first questions I usually get when explaining my idea is “why don’t we just plant more trees, they’ve been removing CO2 from the air for millions of years?” And yes, that is not even false.

Look: I love trees, I love forests, I love nature. But Mother Nature alone cannot solve this major CO2 problem anymore — not in our lifetimes.

A short history lesson may further clarify the problem: When Julius Caesar conquered Western Europe, it was largely a pristine forest. Over the next two millennia, most trees were cut to clear land for agriculture, and use the wood for construction and fire. During the industrial revolution, Europe began to mine coal, because there were simply not enough trees left to burn to fire up the steam engines. Ironically, coal itself is made up of plants, accumulated over the course of tens of millions of years, then burned within two centuries.

How can one expect Mother Nature to solve a centuries-old problem with millions-of-years-old fossil fuels in the next two decades?

Humankind has interrupted the natural CO2 cycles so thoroughly, there is no way back along that road. The CO2 problem is a man-made industrial problem, the solution to it will lie in a reverse-engineered approach. Fossil fuels are the culprit, industry has spewed them out, it’s up to us to clean them up now.

Add to that the fact that climate change is actually making it ever harder for Nature to thrive. Weather patterns are getting more and more extreme: from long periods of drought and ever bigger forest fires, followed by more and more storms. It will only get harder to grow anything on the surface of the earth.

In fact, I believe it would be more ethical to give Mother Nature a break and leave her alone. She can take better care of herself than we can take care of her. It’s about time that some swats of the earth become truly “wild” again, without human interference, in order to fulfil their roles as lungs of the earths and buffers of biodiversity.

However, that doesn’t mean Mother Nature cannot lend us a hand in our fight against climate change, for instance by using the power of the ocean.

The majestic Redwoods in Northern California, on a trip while I was doing my PhD at UC Berkeley

3. The sea is paramount in the CO2 equation

When CO2 is emitted in the atmosphere, around a third of these emissions are taken up by the ocean. Water has an affinity for CO2, so the more CO2 is emitted, the more CO2 goes into the ocean. In that sense, the earth’s atmosphere is acting like a big SodaStream. However, as you know, the more sparking the water gets, the more acidic it becomes. Likewise, due to CO2 emissions, the sea is getting more and more acidic, which is harmful for life in the ocean, from coral reefs to shellfish, and throughout the food chain.

Ocean acidification is also called “the other CO2 problem” (next to climate change). Although less frequently talked about, it is extremely serious, a real threat to an ecosystem covering 2/3rds of our planet. Whenever there is a problem with one part of the food chain, the whole system can collapse. Even if we somehow would be able to manage or accept climate change, then still, this problem would persist.

It is therefore of paramount importance to think about CO2 removal strategies from the ocean.

It is crucial to ensure that whatever the process you use, it is completely safe. The truth is that we know more about the moon than about the earth’s oceans. We still haven’t figured out the interdependencies of different systems. If we are to interfere in the ocean, we need to be very certain that we’re not creating any secondary problems with potentially devastating consequences.

Find out of the blue on instagram: https://www.instagram.com/co2outoftheblue/

4. CO2 removal from the sea offers advantages

Although the ocean is under a large strain, it offers a number of advantages when

Environmental: Removing CO2 catches two birds with one stone — ocean acidification and climate change. Moreover, in the sea, there will be a local and temporary improvement of the water quality: if you’re removing CO2 from the sea around a coral reef, the water quality will improve, and this might help in protecting the most vulnerable ecosystems. This is not the case when you’re removing CO2 from the atmosphere: whether you’re removing it in Singapore or Sydney, there is no difference in the global climate change.

Technical: Removing CO2 from water is removing a (dissolved) gas from a liquid, which is easier that removing that gas from another gas, like the air. Moreover, the concentration of CO2 per cubic meter of water is up to 150 times higher than per cubic meter of air, so you need to move less water than air to capture the same amount of CO2.

Logistical: In the ocean, there is plenty of space for floating “CO2 removal islands”, plenty of renewable energy and plenty of oil & gas infrastructure that could be used to inject CO2 back into the underground. In that sense, it is possible to integrate the CO2 capture and CO2 sequestration, which will save transport and logistics.

Economical: Because of the unique combination of the previous advantages, out of the blue also believe that it will be significantly cheaper than existing approaches. After all, the battle over different technologies will not be won by the most elegant approach, but by the cheapest one.

5. No technology is close to ready at scale

When I started out of the blue, what I saw above all, is an enormous gap between what is needed, and what is there. We will need to remove billions of tonnes of CO2 from the environment in the near future, whereas no technology is ready at the gigatonne scale today.

The most advanced options are currently found in planting forests and adapting agriculture, and as I pointed out earlier, this won’t be enough. After all, at some point there won’t be any more fertile land to keep on planting trees on.

I strongly believe that a portfolio approach is absolutely necessary for CO2 removal: there is a need for hundreds of fresh ideas, that will mature into a handful of scalable solutions. Luckily, a lot is happening in the field, and many ideas are currently being developed and tested. Moreover, it is also taken seriously on the policy-front, which is crucial for the profitability of a large-scale deployment.

Whether or not out of the blue will end up ahead in this race is too early to tell, but it would be a real shame not to try.

Isle of Skye trek, in the background there are fish farms, which also suffer under the ocean acidification.


In conclusion, the best argument to push out of the blue, is that CO2 removal will be absolutely necessary in the near future, and there currently is no convincing technology ready at the gigatonne scale. There are advantages to taking CO2 out of the ocean, which will make it cheaper and more scalable than competing technologies.

So, let’s not waste any more time, and let’s catch CO2 . . . out of the blue!



Lennart Joos

PhD chemical engineering👷‍♂️ Founder @ out of the blue 🌊 Fulbrighter 🌎 innovation - climate tech - communication💡 2xTEDx-speaker 📢 (views my own)