Emission Impossible – can we build without global warming? Reidun Dahl Schlanbusch. TEDxBergen

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My research is focused on reducing greenhouse gases emissions in the building industry. However, my degree is actually in nanotechnology. That means I really like molecules. Even the CO2 molecule is a very pretty molecule. It looks like a little ladybug. It has a little black carbon dress and beautiful red oxygen wings. And because of its special little figure, it has the ability to absorb heat. You might already know that the building industry is causing a lot of these little ladybugs, ending up in the atmosphere contributing to global warming. But do you know how much greenhouse gases there actually are in the atmosphere? This figure is illustrating the relative amount of the different gases in the atmosphere. This tiny little thing up here is the amount of greenhouse gas. So, why is there so much fuss about this little thing? Some people claim this figure is showing that global warming isn’t a problem since the amount of greenhouse gas is such a small fraction, and humans are adding an even smaller part.

To me, this figure is showing the opposite, it shows how potent this gases are because without this tiny little red thing the average temperature on Earth would be an inhabitable minus 18ºC. That’s how sensitive our climate is to small amounts of this gas. Out of the human contribution of greenhouse gases, the building sector is associated with about one third. So this figure is really showing me that my research on reducing greenhouse gases emissions in the building sector really can be making a difference. And that’s why my talk today is called “Emission Impossible” and can be built without causing global warming. Humans contribute to global warming because we burn fossil fuels to get energy. Buildings consume energy for heating in the winter, cooling in the summer, cooking, hot water, and electrical equipment. However, if you look at the whole life cycle of a building, we have everything from the energy intensive production of construction materials like steel and concrete. We have the transport of these materials in the global market, we have the diesel machines at the construction sites. In short, we have a huge amount of accumulated emissions long before anyone even turned the lights on in the building.

Not to mention at the end of the building’s life time, construction waste makes up one third of European waste. So with this in mind, it seems very unlikely that we can build anything without causing global warming, and simply impossible to construct a zero emission building. Well, we have research showing it might actually be possible and within the next five minutes, I will teach you how to do it. In order to design a zero emission building, we mainly need to focus on three things: we need to reduce the energy demand in the building, we need to reduce the greenhouse gas emissions from the materials, and we need to produce clean energy on the building. We need to reduce energy demand because the energy that goes into the building is accountable for certain emissions. In Norway, most of this energy is electricity and most of our electricity is renewable hydropower. However, considering that the Norwegian electricity grid is more and more connected to the European electricity grid, coal, oil, and gas are still needed to give us the amount of energy that we need at all times.

Therefore, also the electricity that goes into the building is accountable for certain emissions. So we really need a building with minimal energy demand. We already know how to build that. It’s already possible. Current building codes have a high focus on energy saving in the use face of the building, but are ignoring the impact coming from the materials. Materials contribute to greenhouse gases when they are produced, when they are transported, and when they are waste treated. In order to construct a zero emission building, we need not only to focus on reducing the energy demand but also reducing the greenhouse gases from materials. I will show you just one example. This house is a pilot building for a research center on zero emission buildings. The center is run by Sintef, where I work, and the Norwegian University of Science and Technology.

The building is designed by Snøhetta and is actually built so you can go see it just outside of Larvik, in Norway. This is a picture from the inside, displaying a little more of the materials that were used. In order to reduce the emissions coming from the materials, we need to think about materials that can be produced in a clean way and we need to choose local materials in order to save transport. However, the best is to use materials we don’t have to produce nor waste. Materials we can use again and again. The bricks in this brick wall, are reused from a demolished building, so except for transporting them there, outside of Larvik, they are free of charge in terms of greenhouse gases. In addition, bricks feel naturally cool when it’s hot, and naturally warm when it’s cold. Because they have something called thermal mass.

So by placing this brick wall in the center of the house like here, we get a natural energy saving reducing energy demand and reducing emissions from materials. In order to zero out the last and necessary rest of greenhouse gases that our building has caused, or will cause, we really need to think outside the box. Literally, we need to see the building as a part of the energy infrastructure. We can install solar cells or other sources of renewable power on the building so that the building uses its own clean electricity. If the building produces enough, it can even export electricity to the grid. The energy that the building consumes from the grid is accountable for certain emissions. But if the building instead uses its own 100% clean electricity, over time, we can zero out the emissions that we have spent, because when we feed 100% clean electricity into the electricity mix, we are making the mix a little greener. Looking at the whole life cycle of the building and seeing the building as a part of the energy infrastructure, the building is costing a net zero greenhouse gases emissions.

Is this really possible? Up to date, no one has yet succeeded in compensating all of their greenhouse gases by production of renewable power. It is extremely challenging, especially at the material part. But it is not impossible. This pilot house, in Larvik, came really close, and is an important step on the way to a complete zero emission building. So the general idea of a zero emission building, is to be able to compensate the greenhouse gases that it caused by production of renewable energy. Of course, the emissions that were done, cannot be undone just by renewable energy. I mean, the climate change and the global warming that these emissions caused won’t be cooled down again by solar cells. It is just like– if I do something really stupid, I unfortunately can’t go back in time and undo it. But, at least, I can try and compensate. The idea of a zero emission building is really addressing the key issues of climate change mitigation, because it is reducing the emissions from one of the most important industries, and at the same time, lifting up production of renewable energy.

It’s an idea that is really changing the industry into becoming greener and more sustainable. And that’s why I wanted to share this idea with you today. Thank you very much. (Applause).

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