Climate change is a hot topic right now (no pun intended)! Nations came together at the 21st International Conference on Climate Change in Paris with one goal in mind: figure out how to keep global warming from rising 2°C.
One possible way to reduce pollution and slow down (or even halt) climate change is to use fuel cells for many of our energy needs. Fuel cells, like batteries, produce electricity. The main difference is that batteries use stored energy inside of them to generate electricity while a fuel cell uses electricity from an external fuel tank of hydrogen gas to do so.
What’s so great about fuel cells, besides the fact that they run on what is literally the number one element on the periodic table, is that fuel cells tend to last longer than batteries, which reduces environmental waste. You can also refill a hydrogen tank in much less time than it would take to charge a battery. However, the best thing about fuel cells is that when you put hydrogen and oxygen gas into a fuel cell, you get water! Can you imagine a car that only emits water?
This may sound too good to be true, and unfortunately, it is, at least right now. Hydrogen can only be a clean fuel if it is produced without releasing greenhouse gases or other pollution into the atmosphere. Most hydrogen is produced with the use of natural gas, oil, or coal, so the key is to find a clean, sustainable way to produce hydrogen.
Here, UOIT’s Clean Energy Research Lab (CERL) comes in with a potential game-changer for hydrogen production!
Before we get into what exactly happens at CERL, how does one produce hydrogen cleanly? Think of boiling a pot of water. Water, being made up of hydrogen and oxygen atoms, turns from a liquid to a gas when you have your stove set to 100°C. Now imagine turning your stove temperature up to over 2000°C. In addition to probably burning your house down, you’re splitting water molecules into hydrogen and oxygen molecules.
It’s very difficult to get temperatures of 2000°C, so thermochemical cycles are used to help reduce how much heat is needed. The word “thermochemical” can be broken down as “thermo,” as heat is an important part of the cycle, and “chemical,” as chemical reactions help the hydrogen production happen at much lower temperatures. The heat could be provided from so-called “waste heat” from nuclear reactors, making that heat useful in the end. The majority of the work done at CERL is on developing the first lab-scale thermochemical copper-chlorine cycle, where you only need temperatures of only 500°C to produce hydrogen. Research is also done to see how renewable energy can provide electricity for copper-chlorine thermochemical cycle, such as wind or solar, as well as using geothermal energy to provide heat.
Professors from UOIT, students, and experts from all over the world get involved with the research taking place at CERL. Currently, CERL is working on producing one kilogram per day of hydrogen, with a goal of ten kilograms in the future. Long term goals are to have a full-scale plant making 10,000 kilograms of hydrogen a day! The research at CERL is made possible by the Ontario Research Fund. The initiative of creating a research facility dedicated to hydrogen as a clean fuel for the future started with the idea of working with Bombardier to convert GO Trains from diesel to hydrogen power.
I first had the opportunity to tour CERL with my Hydrogen Power Systems class, to learn more about how this cycle works, and what kind of research and development happens in CERL from Dr. Ofelia Jianu, a Postdoctorate Fellow at UOIT. Upon entering CERL, I was given this diagram of the copper-chlorine thermochemical cycle to follow along with the tour. Don’t worry if you can’t understand it, as you can think of this diagram as a reference map of what the Clean Energy Research Lab looks like. It was really interesting to find out that there are different rooms to carry out different parts of the cycle shown.
(figure taken with permission from EIC Climate Change Technology Conference 2013)
I’ll start by telling you all about the electrochemical cell (bottom of the diagram), which is where the hydrogen production actually takes place! The electrochemical cell here is a device where you can send electricity through a mix of hydrochloric acid (HCl – here is where the hydrogen currently is) and a solid substance called cuprous chloride (CuCl) to get a chemical reaction where the hydrogen is extracted. The hydrogen has been produced, but the job isn’t done yet!
What makes the copper-chlorine cycle so environmentally friendly is how every chemical, besides oxygen and hydrogen, are recycled continuously. Now comes the question: How do we get everything back to how it started to make more hydrogen?
The next step is taking the leftover cupric chloride (CuCl2) from the hydrogen production step and drying it to prepare it for the next big reaction. In the same room as the electrochemical cell is this spray drying unit, which would use the waste heat from a nuclear reactor on a full-scale version of the copper-chlorine thermochemical cycle (top right corner of the diagram). When dried, the cupric chloride looks like green rock candy!
After that, like an instant pancake mix, just add water! Our green rock candy goes through a hydrolysis reaction in the machine shown below with help from the steam flow meter also shown (top of the diagram). If you refer to our roadmap above, you’ll notice this part of the cycle happens at 400°C! Hydrolysis is the process of breaking chemical bonds using water, meaning the water is used to help us get back the hydrochloric acid needed for hydrogen production in the first step, while giving us a new solid substance called copper oxychloride (CuOCuCl2).
Now is when things get really hot! High temperatures of about 500°C are used to break down the copper oxychloride into oxygen gas, and the cuprous chloride also needed for the hydrogen production to take place in step one (middle of the diagram). We have finally come full circle!
This is what the oxygen production reactor looks like, as well as where a lot of research takes place. Researchers look at different aspects of the cycle, such as what can be done to recover heat to use again in the cycle, and of course to prevent explosions!
In the same room, experiments taking place with this machine have to be closed off in a fume hood, as you would need respirators otherwise.
Of course, you can’t have a research facility without something that looks like it came out a Sci-Fi movie!
The kind of research taking place at CERL is incredible! Ofelia also showed us a machine she used to do research with, which captures bubbles at different heights of the tube, for modelling what happens when hydrogen and oxygen flow through water.
You can’t have a system with the word “thermo” in it without some research dedicated to heat engines and heat pumps! Here is one heat engine that was used for research.
I also got a chance to check out the kits used for youth outreach. Classes can either come to CERL for a field trip or have a guest from CERL come to their classes. High school students have the opportunity to learn how hydrogen and fuel cells work by building their systems of producing hydrogen, then using it for electricity.
Here is a setup of a solar panel used to send a small amount of electricity through water to make hydrogen and oxygen gasses, and then a fuel cell using the hydrogen and oxygen to turn a motor. It’s fascinating to think of how this small system could one day be implemented on a large scale.
You can check out clean energy workshops available at CERL online.
Keep in the loop with clean energy advancements by following CERL on twitter.
Are you interested in the future of clean energy? What do you think of hydrogen’s role as a clean fuel for the future? Let us know in the comments below!