To keep our homes toasty warm, we rely on propane, natural gas and oil, all of which come at a price – Not only are they quite literally pricy, but they also come at a cost for our environment. After all, they cause dangerous amounts of carbon dioxide to be pumped into the atmosphere. In order to put a stop to ongoing climate change, the EU has committed to cut its greenhouse gas emissions by at least 40 per cent by 2030. Fortunately, bioscience engineers at KU Leuven might just have discovered a way to speed that process along considerably: a solar panel that converts sunlight and air into clean burning zero emission hydrogen.
Solar Hydrogen Panels Convert Sunlight into Eco-Friendly Gas
As part of the EU's 2030 climate and energy framework and contribution to the Paris Agreement, the EU has put in place legislation to reduce emissions by at least 40 per cent below 1990 levels by 2030. In November 2018, the European Commission’s new climate strategy included scenarios that reached net-zero emissions, i.e. when the amount of carbon dioxide released on an annual basis is zero or negative, by 2050. It was estimated that at least an additional €290 billion in investment each year would be needed to meet that target. In recent years, it appears that innovation, including progress on renewable energy and energy efficiency, has been the main driver behind the reduction of emissions. Obviously, Flanders does not want to lag behind in this international quest to save planet Earth, and it is high time we get to grips with our energy supplies.
When physics meets chemistry
This is where a team of bioscience engineers from KU Leuven’s Center for Surface Chemistry and Catalysis come in. For over a decade, Professor Johan Martens and Drs. Tom Bosserez, Jan Rongé and Christos Trompoukis have been developing a ‘solar hydrogen panel’, i.e. a solar panel that can create hydrogen from the water vapour in the air. Using sunlight, moisture taken from the air – i.e. no liquid water – is split into hydrogen on the one hand, and oxygen molecules on the other.
The panel is able to directly convert no less than 15 per cent of sunlight into hydrogen gas, Which is a world record. The innovation speeds the production process up to the extent you can actually see hydrogen bubbles appear as sunlight hits its surface. This unique combination of physics and chemistry manages to produce an average of 250 litres of hydrogen gas a day. And that is taking into account our less than sunny Belgian weather! Moreover, production of hydrogen using these panels is more efficient than conventional methods of creating the gas: to get through the winter with enough heat and electricity in a well-insulated house, you would need a mere twenty of them.
Now, when it comes to reducing our carbon footprints and our goal to increase energy efficiency, hydrogen is a well-loved element. Indeed, when burned with oxygen, hydrogen produces water and little else. Hydrogen fuel is therefore a zero emission fuel. In addition, hydrogen energy contains three times the amount of energy per kg compared to gasoline and other fossil-based fuel sources. No wonder hydrogen is used to launch spaceships! And the great thing is, we have a lot of it: at 75 per cent of the normal mass of the universe, hydrogen is the most plentiful element that we know of today.
However, as hydrogen is extremely reactive and light, it tends to either react with something in our atmosphere, or simply float off. So, the use of hydrogen as a fuel depends on a successful production process, as well as the carbon footprint of said process.
Wanted: a clean production process
Nowadays, most hydrogen is produced from natural gas. During this process, carbon dioxide is emitted. Although it pollutes less than other fossil fuel sources, this process is definitely not as environmentally friendly as some might claim. Of course, we can also produce hydrogen from renewable resources, but, as it stands, this is currently too expensive and has technical limitations. Using the KU Leuven solar hydrogen panel to produce hydrogen, we can benefit from a number of important advantages compared to the renewable alternatives.
For one, it is a lot cheaper to produce hydrogen using their invention compared to with electricity (electrolysis) generated by ‘traditional’ solar panels. Furthermore, electrolysis cannot just take place anywhere. Air, however, is all around us, meaning the hydrogen panels can be used anytime, anywhere, and at any scale to produce fuel. In addition, this technique does not involve liquid (drinking-)water; the moisture in the air suffices.
Another interesting characteristic of hydrogen is that, unlike electricity generated from solar panels or windmills, it can be stored in large amounts for extended periods of time. Excess amounts of hydrogen produced in summer, for instance, can easily be stored away, and used in wintertime to heat or produce electricity. In addition, compared to more ‘traditional’ systems that generate hydrogen, these panels do not rely on liquid water. For that reason, they can be installed just about anywhere, not unlike the solar panels we are all familiar with. Without the need for a connection with the electricity grid, energy can be stored as hydrogen. By converting hydrogen gas in fuel cells into low-voltage, direct current electricity, vehicles and buildings can be supplied with the energy they require.
Hydrogen in every household?
The panels are still a long way from large-scale commercial production, but they are ready for a full real world trial. In Oud-Heverlee, the latest prototype of the solar hydrogen panels is being tested in everyday living conditions. Leen Peeters, a 41-year-old entrepreneur and KU Leuven PhD, does not live completely off the grid, yet her home is dedicated to generating and storing its own power. On top of solar panels, a heat pump, larger than life batteries, and a Tesla, it will now also be equipped with twenty of the KU Leuven research team’s unique panels. One of the aims here is to find out how weather conditions influence the panels. If this experiment, which is funded by VLAIO, turns out well, a further 39 family homes in that neighbourhood can be fitted with the panels, and the bioengineers can start thinking about mass-producing them.
So, when will that be? Although optimistic, the research team is still unsure about the exact date. At the moment, they are gearing up to spend the next couple of years focusing on the panels’ small-scale development. By working out all the kinks along the way, Professor Martens and his team hope to deliver a top-notch commercial product, ready for use in various contexts, from agricultural settings, retail to transport and remote communities. As Reuters has ranked KU Leuven as Europe’s number one innovative university for four times in a row, you will not be surprised to hear the team is also considering a spin-off. An exciting collaboration with LRD, or KU Leuven Research & Development is definitely on the horizon.
Even though the problems our climate is facing go far beyond our depleting energy supplies, it is clear that hydrogen can play a crucial role in our transition to a more carbon-neutral world. Professor Martens and the rest of team have made another important step towards that goal with their solar hydrogen panel. A chemical means to a climate-friendly end!