Bill Spence, Independent: Being positive about going negative

Bill Spence: Thank you, Sarah, and I'm delighted to be here with the opportunity to speak to the Climate Assembly. I am Bill Spence, I'm going to speak to you about greenhouse gas removal, particularly being positive about going negative. I am an engineer, I've been an engineer for the past 36 years, and for about half of my career, I've focused on trying to find and bring oil and gas out of the subsurface, into the atmosphere. About midway in my career, I realised the problem I was creating and I switched to learning how to identify that CO2, capture it, and put it back underground. So I feel particularly adept at sharing with you both the emissions and the capture side of this technology.

So let me take you to slide number two with an overview of my presentation. So, I will give a brief summary of why we need to do greenhouse gas removals, what nature has done in past history to safely remove greenhouse gas, take you on to how much removal we need to do and the cost involved, and then a quick overview with my conclusions.

I'll take you to slide three. So why do we need to do removals? Well, we're on the verge of filling our atmosphere with more CO2 than is safe for mankind. Our atmosphere is incredibly thin. And if in the next 30 years by 2050, we want to get the net zero, we need to slow the release of CO2 and launch a concerted effort of greenhouse gas removals to result in net zero. So it isn't an either-or. We've got to do both. Slow the emissions and increase the net removals.

Let me take you to slide number four where we go through what nature has done. I would like to make the point that nature has done this safely before, and I take you back 65 million years to when the dinosaurs roamed the earth. When the dinosaurs were here, CO2 levels were five times higher than they were today. So nature has figured out how to bring those levels down, and its used two key routes. Nature removes CO2 from the atmosphere using trees and creating rocks. So if I explore the tree side, the trees act to take CO2 out of the atmosphere and turn it into plants that those plants in due course will break down and become soil or peat, and that in some cases became buried and covered in the deep subsurface that became coal and oil and gas. On the flip side, we see it can also create rocks. CO2 comes out of the atmosphere to make rocks as we see in the Atlas Mountains in North Africa, the Rockies in Canada, the white cliffs of Dover here in the UK. Both of these routes offer safe, long term, proven storage. The only issue is that nature has had 65 million years to bring these levels down, and we need to do this a million times faster. So what we were fortunate to have, is we've got a number of scientists and burgeoning businesses that are already learning how to do this a million times faster.

And I take you to slide five. Look what really can be done at scale and speed based on how nature has done it in the past. So starting with tree based, you're going to the rock based ones. These squares that have now appeared on your screen represent the scale of capture and storage, greenhouse gas removal that can be done by various methods. The first is backs bio Energy plus CCS, and we heard Chris talked about that earlier. This is using plants to absorb the CO2, we then take those plants, burn them down, and the CO2 goes deep underground, but allowing us to use the energy that those plants have stored from the sub. We could do something in the order of 50 to 100 million tonnes of CO2 per year using backs. The second option, second biggest square, is using forest soil and wood in construction. So instead of taking all of the CO2 and putting a deep underground, what we learned to do is use that carbon-based material at the surface to make sure our soils continuously get better, our forests get bigger, receive more and more wood structures that store the CO2. That has something in the order of 10 million tonnes of CO two per year potential. Going down another scale is the idea of direct air capture, and this is where mankind is, in essence, simulated a tree. A device, which is able to pick the CO2 out of the atmosphere, capture-- just as a tree would-- captured and then we put it deep underground. Smaller again at 1 - 5 million tonnes of CO2 per year through director capture, and the fourth option is the one turning into rock. Now we see it has the smallest potential at present, and whether this is one of those options that has something at present in the order of a 1,000,000 tonnes per CO2 per year. So this is our current projection of where we'll be in 2050. Now, the question is, with these options, just how much do we need to do if this is how much we can do?

And I take you to slide six. Here I use a little needle gauge to show where I think we're going to be in our best case, the best case being that we only need to tidy up after airplanes, or aviation, and agriculture. So I'm assuming everybody else has done their job, and all that's left to tidy up is aviation and agriculture. So greenhouse gas removal isn't an excuse for inaction, it is for those difficult sectors. And we're looking at something in the order of 50 million tonnes of CO2 per year as our best case, so delivering 50 million tonnes per year would be a challenge, but it's doable. And what's important is to understand the cost involved in doing this cleanup of the last 50 million tonnes. And I show a small box to the top right where you look at the greenhouse gas removal costs. To do this last 50 million tonnes, to tidy up from aviation and agriculture, we're going to spend something in the order of £10 billion per annum. Now if I wind back and we look at the entire budget to get to net zero of replacing the automotive fleet, tiding up industry, agriculture, power, all of that cost-- about 1/3 of that, 33% of that, will need to go to tidy up this last bit during greenhouse gas removals. So it is an expensive option, but the last bit is always the most expensive.

So from here I will take you to slide seven. So if we are to deliver 50 million tonnes of CO2 removal in any given year, it is my opinion that we're going to need about 3/4, 75% of that, to be done with backs biomass plus CCS and the other 25% to be done by increasing forest areas, capturing more CO2 in the soils, using wood and construction, utilising technologies that direct air capture and storage, and enhanced weathering. The combination of but 3/4 specs backs, 1/4 the other options in order to meet the greenhouse reductions we need.

And I take you to slide number eight. It gives us a summary of where we will be in the event that many of the sectors, many of the parts of our economy don't clean up as much as they should. And I show across the bottom a number of little icons. If we say that not just planes and agriculture fail to get to zero, if buildings, industry, power, shipping and automotive failed to get there, we end up in a maximum case now shown by my little needle gauge shown in the red. 90 million tonnes of CO2 per year. That's because you're really starting to bump up against the limits of what we can do with carbon capture and storage, what we could do with biomass and tree availability. All of these things started to bump up against the limits of what we can do. So it's important that we don't leave ourselves in this position where we're having to tidy up after a number of parts of the economy who don't do their job.

Now, at this point I need to make it very clear as I go to slide number nine, that the intention is not for us to damage the forest and the wetlands to fix the atmosphere. We're not about moving the problem from one place to another. It's about doing both sustainably. Our forests and wetlands provide clean air, habitats, livelihoods, soil stability, medicine, just to mention a few. We can't afford to lose that, so sustainability must be core to greenhouse gas removal. And I don't think this comes as a surprise to any of you.

So in summary, wrapping up, I take you to slide number 10. We have five key elements to chase after here. First, like all good things that you acknowledge, you've got a problem. There's too much CO2 in the atmosphere. We need to slow emissions and start removals with acknowledging the problem. Second is to look at the wide range of opportunities we have and continue to develop a broad range of greenhouse gas removal solutions, all the way from rocks to forests and all of the knock-ons that they bring. The third one is to acknowledge we're going to have a heavy reliance upon trees, forests and biomass. So to start now, to secure fair, potentially international deals to ensure a long term access to sustainable forests, plants, and wetlands. We need to have a place to put all of that CO2, so the fourth thing we need to do is launch and grow an extensive carbon capture and storage network. It is already starting around the world. The UK has a good lead but has not yet executed one of these. It needs to start soon. The final piece in this summary is the recognition of how much we need to do. 50 million tonnes of CO2 by 2050 is a lot, and we need to start now if we're going to get to that level. So, Sarah, I wrap up at this point and I look forward to taking questions. Thank you.