Water Evaporation: A New Weapon in the Fight Against Climate Change?

Photo by Markus Spiske on Pexels

Climate change sucks.

Nowadays, it seems like we hear that a lot. So much so, that the actual meaning behind it has started to diminish. While it’s true that we’ve made extensive progress in the last few decades, our world is still far from perfect.

Today, about 1.2 billion people worldwide are living with little to no electricity. But for those that do have access to energy, nearly 84% of that comes from non-renewable sources such as coal, oil and natural gas.

Well, what about renewable energy?

In efforts to switch to a greener world, we’ve seen a ton of hype around alternative energy sources like solar panels, wind farms and geothermal power plants. But it turns out we are a LONG way from reaching the UN’s net-zero emissions by 2050 goal. In the US alone, renewable energy sources only make up 12–15% of the annual energy consumption, despite being one of the wealthiest countries. It really makes you wonder, if these energy sources work so well, why do they play such a minor role when it comes to total energy consumption?

Although there are several factors underlining why we don’t use more renewable energy, three major factors are driving us away from them.

1) Inconsistency

Currently, renewables are too inconsistent; the sun doesn’t always shine, the wind doesn’t always blow, you get the point. Even if we were to overcome these issues, geography and seasonal variations would make it extremely difficult to apply these technologies globally at scale. These fluctuations make them unsuitable for some environments, which causes them to become supplementary sources of energy since there’s no guarantee you’ll have the same power generated between two days.

For some additional clarity, here’s the energy generation of a wind power plant in contrast to the energy demands of a city:

Wind Power Plant vs Citywide Demand

2) Resource Intensity

When people think of renewables, one of their first thoughts is that these sources are environmentally friendly, which is a bit misleading. While they may not produce direct emissions, they require significantly more minerals and resources than other energy production methods. Especially today, with the global chip shortage, being able to manufacture and mass-produce “green” technologies like electric vehicles and solar panels is not only problematic but highly resource-intensive. Worse yet, most of these materials will end up as debris after their 20-year lifespan.

Debris From Damaged Solar Panels

3) High land usage

In my opinion, the most flawed part about renewables is their extremely poor power density, which is about 1000x less than natural gas. In other words, we would need to build 1000 solar farms to produce the SAME amount of energy as ONE natural gas plant. This results in more deforestation, local community displacement, extinctions, and less land available to feed an ever-growing population. I mean just think about it; our earth is 30% land and 70% water, yet we continue using more and more land.

Windmills Require a Ton of Land

At this point, we need a new form of renewable energy. One that can provide a consistent amount of power, isn’t very resource-intensive and doesn’t require much land usage at all. Most importantly, we need it NOW.

Well as ridiculous as this might sound, there might be a new way to generate energy while avoiding the previous flaws. A unique energy source that has the potential to generate 365GW of energy per hour, or fulfill over 70% of the US energy consumption.

I’m talking about Evaporation.

How It Works

You’re probably a little confused, and I don’t blame you. How could we possibly harness the water cycle for energy? Well, it’s a bit more complex than that. But before we get into the specifics, let’s briefly go over evaporation.

In terms of the water cycle, evaporation occurs when sun rays warm the surface of the water. The heat from the sun forces the water molecules to vibrate faster and faster until they move so quickly that they escape as a gas (or vapour). Once in the atmosphere, the vapour condenses to form clouds and eventually precipitates back to the ground in the form of rain or snow.

But now let’s imagine that the vapour for whatever reason, built up and was unable to leave the surface.

Well, that’s essentially what we want to try to accomplish with large-scale Evaporation Engines.

In a 2015 paper published by Ozgur Sahin and a team of scientists at Columbia University, they reported the use of microscale devices that could generate small amounts of electricity using water. In these devices, bacterial spores are grown on films and placed underneath shutter-like structures. The spores swell and shutters open as humidity increases, allowing moisture to escape. As a result, the spores dry out and contract, allowing the shutters to close. During the repeated opening/closing of shutters, a generator can turn that force into electricity.

How the Evaporation Engine Works

In simpler terms, when water molecules are turned into vapour, we want to trap them beneath these shutters instead of going directly into the atmosphere. Combined with a special type of bacterial spore, we have a device that generates power, simply through changes in humidity levels.

Looking Beneath the Shutters

In the prototype above, a yellow layer of tape stretches across the length of the shutters. These tapes contain millions of spores called Bacillus subtilis, which can exist in a dormant state for hundreds of years. What makes them unique, however, is their ability to expand and contract; just like a muscle. Interestingly enough, Bacillus subtilis spores can continue to perform the necessary mechanical motion even when they are dead.

So when the shutters of the evaporation engine are closed, it creates a humid environment that these spores require for expansion. Then once expanded, the shutters open, which allows the vapour to escape. This forms a less humid environment allowing these spores to contract again, and as a result, close the shutters. This continuous cycle of growing and shrinking bacterial spores that open and close the shutters are connected to an electromagnetic generator that produces a constant supply of energy.

The power that is produced by the generator will be transported to the grid using similar infrastructure to floating solar farms, but it will eliminate the single most expensive thing that floating solar farms require; energy storage. The average price to store energy in the US is a staggering $625/kWh. Since evaporation is a constant process, the energy generated is consistent, which is why we can eliminate the storage cost altogether.

Now that just about covers the technical side of Evaporation Engines. But there are still a few obstacles preventing us from bringing this technology to a larger scale. So let’s take a closer glimpse at how these devices could be implemented and what barriers still remain in our way.

Looking Into Implementation

The initial step to bringing this concept to reality is assembling Evaporation Engines on a larger scale. Currently, I’m estimating a cost of $512 USD/m², which includes materials like the base, shutters, films, bacterial spores, plus assembly. At first glance, this may seem a little steep. However, it is crucial to note that solar panels typically cost ≈$400 USD/m², and when factoring in their energy storage aspect, solar panels are actually less economical compared to Evaporation Engines.

Once past the developing phase, we can begin to look at launching and eventually expanding the device. The process should pilot in the United States, where they can be built on three different coastlines between 2025 to 2027.

Starting in 2025, Evaporation Engines should be deployed on the northern coast. Following the project’s success, it would make economic sense to expand to the southern coast in 2026 and then start a new project on the west coast by 2027. If the pilot in the US has been a success and the devices are able to generate extensive sums of energy, we could expand the concept globally and eventually bring energy to the hands of those in need.

US Expansion Timeline

In case you’re wondering what costs will look like, here is a rough breakdown of the implementation expenses:

Annual Cost Breakdown

Although the initial costs will be high, we can focus on immediately generating revenue as soon as the Evaporation Engines are operational. In order to pay for the initial cost of the devices, we can make PPAs (Power Purchasing Agreements) with energy suppliers and sell the electricity at a flat price of $0.4 per kilowatt.

Up until this point, I have only outlined the potential advantages and benefits of this technology. Yet if all this was already possible, the notion of an evaporation-driven world would likely be a reality and not just an idea. Unfortunately, there are a few things we need to figure out before we see this device utilized on a macro scale.

What’s Holding Us Back

Photo by Melissa Bradley on Unsplash

1) Altering Weather Patterns

The most important thing to understand before installing these devices is their influence on a region’s climate. It’s difficult to determine exactly what shifts would occur in the water cycle if these devices were to be deployed on a large scale. That being said, to generate the bulk of the country’s electricity, these engines would need to be installed on every inland body of water in the US, which is both ecologically and physically impossible. Nevertheless, shifting the project to the coastlines poses a similar risk when it comes to precipitation. Since the engines involve retaining vapour underneath the shutters, it’s tough to infer the amount of vapour that will be lost when the shutters do eventually open, and how that will affect rainfall patterns.

But this isn’t all terrible news, either. When we focus on one of the most consequential problems associated with climate change, increased precipitation, things start to become interesting for us. In the majority of regions, a reduction in water evaporation is actually beneficial to us, since it minimizes excessive rainfall. In other words, as climate change worsens, the technology becomes more powerful, and vice versa.

2) Device Durability

Another factor to consider when looking at large-scale Evaporation Engines is their longevity. One of its most significant advantages is that it can be manufactured from cheap biological materials that are easier to dispose of than solar panels. However, the combination of these biodegradable and cheap materials comes at an expense: durability. If these devices were placed on coastal waters, there’s always a chance that a storm could ruin the devices and leave the area toppled. With this in mind, the ideal engine would have to be made to withstand numerous unpredictable weather conditions while keeping costs relatively low.

It’s crucial to note that water itself doesn’t affect bacterial spores and their ability to function, especially since these spores retain their muscle-like property even when dead, which means that unless completely demolished, the devices will continue to operate.

3) Cost

The ultimate hurdle preventing us from seeing this technology on a large scale is, unsurprisingly, cost. Although the proof of concept and technical aspects of an Evaporation Engine exists, much more research and development are required to make it a reality. We aren’t moving forward with this device because of the lack of ambiguity and risk, but as more money is poured into development, we may see the first practical trials running within the next year or two.

Final Thoughts

Climate change remains, at the end of the day, one of our greatest threats. From fires to famine, the consequences are beyond real. Even with a dilemma this complex, the solution is straightforward: we need cheaper energy.

Without energy, our world just wouldn’t be the same. However, there is a great deal of innovation and changes being created to address this problem, and Evaporation Engines is just another example. Despite this uncertainty, I believe it is a promising step toward safeguarding our future.

Key Takeaways

  • While many of us worry about controlling our carbon footprint, there are people in our world who don’t have access to power at all.
  • Current renewables don’t play a large enough role when it comes to total energy generation.
  • We need a new form of renewable energy that provides consistent power, isn’t resource-intensive, and doesn’t require much land usage.
  • Using a technology called Evaporation Engines, we could harness the process of evaporation to generate consistent power for up to 70% of the US.
  • These engines work by trapping humidity beneath the device, which allows for bacterial spores to expand and contract. The repeated expanding and contracting causes shutters to generate a mechanical force (through the constant opening/closing) which can be converted to energy.
  • These devices come with three potential drawbacks; altering weather conditions, durability and large-scale development costs. However, as more time and money are invested into this technology, it won’t be long before we see it being used in real-world trials.
  • This technology holds so much promise for resolving the current energy crisis and developing an entirely new method of generating renewable energy that is cheaper, efficient, and reliable.

If you’re still here, I appreciate you checking out my article and I hope you discovered something worthwhile. If you like this space or want to learn more about the idea, check out this video in which I present the project and receive feedback from a panel of expert judges.

Presenting to a Panel of Real-World Experts!

Let’s Connect!

If you enjoyed reading this article or learned something new, I’d love to connect on LinkedIn. If you’d like to stay updated on my recent articles or projects, you can subscribe to my newsletter here!




Hey, I’m Girik, a 16-year-old based in Toronto interested in blockchain technology and web3

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Girik Narang

Girik Narang

Hey, I’m Girik, a 16-year-old based in Toronto interested in blockchain technology and web3

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