The Economy, Land & Climate Podcast

Can BECCS really provide negative emissions? NRDC's senior scientist Sami Yassa presents new research

February 23, 2022 Economy Land & Climate Insight Team
The Economy, Land & Climate Podcast
Can BECCS really provide negative emissions? NRDC's senior scientist Sami Yassa presents new research
Show Notes Transcript

Sami Yassa, senior scientist at the US based NGO the Natural Resources Defense Council (NRDC) and their scientific lead on forests and forest biomass,  sets out NRDC research on the use of Bioenergy with Carbon Capture and Storage (BECCS) which looks at whether it can really produce negative emissions.  He also explains NRDC's work with the US Congress on biomass.

Further reading from Sami Yassa:

·         NRDC's recent research on BECCS

·         Further explanatory documents and data from the research 

·         NRDC US Congress work around biomass and ensuring scientific independence for US environmental agencies


Find more podcasts and articles at www.elc-insight.org

Alasdair:

Hello, and welcome to the Economy, Land and Climate Podcast. I'm Alasdair MacEwen, and in this episode, and following on from our previous podcasts examining the use of forest bioenergy, I spoke to Sami Yassa, senior scientist at the US based NGO, the Natural Resources Defense Council, NRDC, and their scientific lead on forests and forest biomass, who has recently published research on the use of bioenergy with carbon capture and storage for BECCS.

Sami:

I think the top line message is that the industry greenwashing, chief among them, Drax, is misleading policymakers in the UK and the public and, frankly, their customers. They're greenwashing and they are being deceptive. They are saying that BECCS can produce negative emissions. And they're flatly wrong. They're flatly wrong because these upstream sources are uncapturable.

Alasdair:

I began by asking Sami Yassa to explain his most recent research.

Sami:

Industry proponents like Drax like to claim that biomass for electricity combined with carbon capture and storage produces negative emissions. And their argument, which is largely waving their hands without any real rigor is that they claim that if you can capture the emissions out of the smokestack at the power plant and store those, then you've gotten to zero emissions, and then they argue and if you can regrow the forest, after you've cut it and burned it, then the regrowth sequesters carbon. So overall, you get negative emissions. So they argue that bioenergy with carbon capture and storage is a negative emissions technology and bioenergy with carbon capture and storage we call BECCS. That's the acronym. So our study looked exactly at that question, if you capture stack emissions, and if you account for forest regrowth, can you produce negative emissions? And the answer is flatly No. You don't even come close, you cannot get to carbon neutrality, and you cannot get negative emissions whatsoever. And the reason is twofold. First, there are uncapturable emissions that cannot be captured at the stack. These emissions occur offsite, upstream in the production and transport of pellets. They are simply uncapturable because they occur off site away from the power plant. And one example the energy used to transport the pellets or the energy used to dry the pellets. The second issue is that after a forest is cut, what our study shows is that its ability to sequester carbon is degraded in the scenario that we looked at. So absent bioenergy demand, the sequestration of the forest will be higher than the scenario involving cutting the forest and using those materials in a power plant for BECCS. So let me describe the details. We looked at the supply chain, and we looked at the transport of wood from the forest, the drying of that wood prior to manufacturing the pellets, the processing of those pellets at the manufacturing plant, shipping those to the UK, looked at each one of those steps in the supply chain. And we also looked at what happens in the forest itself after it's thinned. And looking at the sequestration capacity and the rate at which it is drawing carbon out of the atmosphere. The scenario that we looked at is a very narrow scenario. We looked at a scenario in which plantations in the southeast are thinned, and they are then manufactured into pellets, shipped to the UK, and burned in a BECCS plant in the UK. This is a scenario very similar to obviously, the Drax scenario. In a nutshell, the top line results are that when you account for each of these uncapturable emissions, that is the emissions that occur offsite. And even when you assume the stack emissions are captured, you still have a net positive emissions of about 780 kilograms of CO2 for every megawatt hour of electricity produced. Now I want to talk about that number for a minute and put it in context. This is after you've captured the stack emissions, and it's the net of all of these upstream emissions - 780 kilograms of CO2, for every megawatt hour of electricity produced. Well, natural gas produces 360. So just the upstream uncapturable supply chain emissions are double what natural gas produces when you generate a megawatt hour of electricity. Coal is 980, which tells you that the upstream emissions, the uncapturable, emissions from BECCS are about 80% of what's generated in a coal fired plant. So even if you're capturing the stack emissions, you cannot get to zero carbon and you cannot get negative.

Alasdair:

Can you say a little bit about, first of all, how you calculated those emissions? That'd be really interested to know what what the methodology was behind the research, essentially.

Sami:

There were two methods of calculation, and each segment of the supply chain is a little different. There's the transportation of wooden pellets. There's the drying of wood, we just drew the numbers directly from the literature, there was no modeling, there was no real calculation. It was just what does the industry say about the amount of carbon emitted associated with this upstream process. And in fact, in a couple of cases, we use Drax's numbers themselves. So for example, with respect to transport and processing, there was a range of values, all within a fairly narrow range, including the estimate from Drax. Drax came in on the low end. But we use Drax's number and it was about 100 kilograms of CO2 for every megawatt hour of electricity produced, just for transport and processing. The numbers for heating the wood prior to pellet manufacture, again, it's straight from the industry literature. It's just basic physics that's published, because you need to get to a certain moisture content in order to produce the pellets. We know the starting moisture content, we know what they need to do to dry them. And this is published by numerous sources. So that was straightforward. On the question of forest regrowth and what's called foregone sequestration, that involved modeling by our analysts, a firm that we hired to do this research, Hammerschlag LLC. And in that instance, it was also very straightforward. The way you look at emissions from forest harvesting, the resulting net emissions that are generated, is you look at how does a forest grow absent bioenergy demand? That's a very easy projection. It's done over and over and over in the literature. It's just a standard curve that's used for what's called growth and yield projections. Because forest landowners want to know, you know how much wood they're going to have to harvest, you know, 20 years out, or 30 years out. And they use growth and yield projections that are standard growth curves. So you take a plantation in the southeast, and there are very well established growth curves, which we use to project what happens absent bioenergy demand in a plantation, then you do a scenario where the forest is thinned, namely, you remove some of the trees. And there again, you have a projection and these projections are very, very well established. And so the modeling simply involves comparing the growth of the forest looks like absent bioenergy demand, and compare that to what the growth of the forest looks like when you have a thinning operation that's introduced. The result is that thinning degrades the ability of a forest to sequester carbon compared to what would have happened absent the demand for that thinning. And that was the essence of the modeling. So let's just use an example. Let's say you've got a forest acre with 100 trees on it, and those 100 trees are going to grow at some rate, let's say at age, the forest reaches an age of 20 years old. And those 100 trees are each capturing one unit of carbon from the atmosphere. So that acre is drawing down 100 units total if each of those trees is drawing one unit and there's 100 trees. Okay, so that's cool. 100 units are captured if you don't do anything to the forest. Now you go in and you remove a bunch of trees. You got 30 trees left in the forest after thinning, which is pretty typical of a thinning operation. And let's even say that those trees are now going to grow faster because they're getting more sunlight and water. That's the whole idea behind the thinning operation, the sequester two units. Well, now you've got 30 trees securing two units, which is 60 total on that acre. So you've gone from the ability to sequester 100 units of CO2 down to the ability to sequester 60. And that's the gist of this analysis.

Alasdair:

Can you say something more about the significance of this research? And why is so significant for for listeners?

Sami:

I think the topline message is that the industry greenwashing, chief among them, Drax, is misleading policymakers in the UK and the public and ratepayers and frankly, their customers. They're greenwashing and they are being deceptive. They are saying that BECCS can produce negative emissions. And they're flatly wrong. They're flatly wrong, because these upstream sources are on capturable. Point number one. Point number two, when you thin a forest, you degrade its ability to sequester so their whole line about forest regrowth adding negative emissions is flatly wrong. The significance is that we looked at this question, in a scenario very, very specific to what's occurring right now. Namely, plantation thinning production of pellets, export to the UK and burning them in a power plant. In the UK.

Alasdair:

Are there any scenarios where you think BECCS with wood and burning burning wood could produce negative emissions?

Sami:

I don't see it. And the reason you cannot get negative is that you cannot get carbon neutral in the first place. So when you remove wood in a forestry operation, and burn it to produce electricity, you cannot get to carbon neutrality. Because you've created a carbon debt, you have released that carbon into the atmosphere immediately, instantaneously. And all scenarios involving forest biomass assume, well, we're going to mitigate that over time, we're going to mitigate that through forest regrowth, or that's going to be mitigated because those materials would have decayed anyway. There's all kinds of quote mitigation arguments that the industry likes to put forward. But even if you take them at their word, that there's mitigation in the future, from a forestry biomass operation, that mitigation takes time to regrow the trees. And it takes time to restore the carbon in the forest the way it was, that time is typically many decades. That's well beyond the timeframes we have to address climate change. And so it does not pencil out in the timeframes that matter for climate change. Even if you assume the industry's most optimistic assumptions, which themselves are flawed. Let's take a company like Drax. Drax says, oh, forests regrow, it's fine, we're doing fine, forests regrow in the southeastern US. Drax has no jurisdiction or authority to ensure that those forests are replanted, to ensure that they grow at the rate that they claim they will regrow at or to ensure that the landowner doesn't turn around and sell that forest and turned it into a parking lot. Drax has no authority or jurisdiction over ensuring that any of their promises will actually bear out the way they claim.

Alasdair:

But Drax would argue that, you know, they they now own their own plantations on quite a large scale. And that's on an increasing scale, surely,

Sami:

same thing, they can't guarantee that the rate of forest regrowth is going to occur at what they project, they can't guarantee that a fire isn't going to burn through that forest after they've cut it and changing the whole scenario. I mean, they can't predict the future. And it's nonsense for them to be making these promises to policymakers about carbon neutrality and net negativity, based on general statements about forest regrowth. It's like you go to a bank, you apply for a loan for a home mortgage, and you say, oh, don't worry, I don't have any assurances or numbers that I'm going to be able to repay you but just trust me. Is the bank going to say yeah, no problem? There's no documentation evidence. You don't have a job, and you know, we don't know how you're going to get your income, and they don't think that way, and there's no reason policymakers shouldn't be thinking that same way.

Alasdair:

Has Drax responded actually, to your research?

Sami:

I don't think they responded directly at the time. There was a slew of reports, one from Chatham House, and they issued a bunch of negative statements generally. And, you know, just their standard rhetoric, no real, substantive response.

Alasdair:

I mean, that brings me on to the question that in previous podcasts that we've had, we've we've spoken to other scientists about biomass, and about BECCS. I mean, we spoke to Duncan Brack from Chatham House, we spoke to Dan Quiggin also from Chatham House, who's been doing some some other research on Beck's. We've also spoken to John Sterman at MIT, and to Phil McDonald from Ember who's been looking more into the costs of BECCS. I just wondered if you could try to place your research within these other pieces of research that were also going

Sami:

I think that we tried to do two things that might have on? made it more distinct. The first is we looked expressly at a very narrow scenario. So we did not reach conclusions about BECCS generally. And we didn't suggest that these conclusions are general, we looked at a very narrow scenario involving plantations and the thinnings. And the export and and BECCS in in the UK. And the reason is, is that more and more, the industry is saying we're using low grade thinnings. And the presumption is that that's a better solution than other forms of forestry. This research shows that, even in that same scenario, you have some very bad, very bad outcomes, like I said, 80% of the emissions from coal. The second thing is that we looked at the full supply chain, from the very start, where you're cutting the forest through the drying and processing and transport. And we looked at, again, the foregone sequestration element as well. So we accounted for these uncapturable emissions in a very systematic way through the supply chain.

Alasdair:

I just wanted your view on why BECCS is becoming such favoured technology in modeling, etc. and why you think that it seems that modelers are still using BECCS in quite large amounts. I mean, the industry would point to the IPCC and others having quite huge amounts of BECCS for their greenhouse gas removals in their models, and I just wondered if you had an opinion about why that was.

Sami:

Okay. So this is a very important question. Industry proponents, like Drax, have co opted and misrepresented IPCC modeling, and modeling outside of the IPCC analyses. If you look at the IPCC reports on BECCS, the first thing you see is that the biomass that they looked at the integrated assessment models uniformly focused disproportionately on biofuels. So the BECCS analysis that they're looking at, if you dig into these models, you see that they are looking at low carbon energy crops, short rotation, energy crops and agricultural residues predominantly to be used in biofuels. Very, very small portion and this is in the IPCC reports themselves. A very small proportion of the inputs and modeling relates to woody feedstocks, forest feedstocks and electricity production. The prospect of BECCS as contemplated in that integrated assessment models has nothing to do with wood for electricity, for the most part, and the results are not representative of wood, forest materials for electricity. The results are representative of low carbon agricultural residues and short rotation energy crops for biofuels. So they've co-opted this, just because the word biomass appears in these models, they've adopted it. And it's very plausible that agricultural residues and low carbon short rotation energy crops for the purposes of biofuels, when used in conjunction with BECCS would produce negative emissions That's a very plausible scenario. Because you have such short rotations, you can achieve carbon neutrality. My guess is that the modelers have focused on on that issue, that the industry has co-opted that issue. But secondarily, another reason that the modelers choose to look at BECCS is that people are looking for a net negative solution. We know we have to get net negative by mid century. And so the real solutions don't lie in producing forest biomass to produce electricity. They rely on natural climate solutions, you know, a whole suite of other approaches that have nothing to do with the approach contemplated by Drax. I really think this point is so important that the BECCS modeling in the IPCC and the suggestion that BECCS might be able to produce negative emissions is not looking at forest materials for electricity full stop.

Alasdair:

It's interesting you say that, because I think that's an assumption that probably at least many people have made, which the BECCS model is involving woody biomass.

Sami:

Yeah. And again, it's not that it doesn't involve it at all. But the component of woody biomass doesn't involve trees. Where it does appear it doesn't involve trees, it involves harvest residues. And when it does appear, it's a residue that is in very, very, very small proportions. It's sort of sometimes lumped in with agricultural residues. Each of these models, integrated assessment models is somewhat different. And of course, the IPCC just aggregates those results. So it's just not representative of what Drax is contemplating and what many people claim.

Alasdair:

I'd like to move on to your kind of work in the US or not only this, this piece of research, what stage is biomass and BECCS at in in the US with the Biden administration?

Sami:

we are trying to ensure that federal government policy through Congress, and the administration doesn't repeat the same mistakes as the EU and the UK. And what was that mistake? It was fundamental, it was an erroneous scientific assumption that forest biomass is carbon neutral. That was the foundation for the subsequent subsidies and other forms of support that drove this expansion. Absent those subsidies, a company like Drax simply could not survive economically. I mean, that's well established. So we know that the subsidies are the driver of bad outcomes. And the subsidies are justified through this false notion that forest biomass is carbon neutral, just because again, the generalised claim that forests regrow. So thankfully, in the US, we have not reached the point where there are federal policies that establish carbon neutrality of forest biomass. But that's not to say that industry proponents aren't working hard to get there. There is a concerted effort by the industry and their proponents in Congress in the US Senate in the US House of Representatives to establish carbon neutrality as a matter of fact, federal policy that takes the form of what's called a rider to the must pass appropriations bill. So how does that work? Every year, US Congress has to fund the agencies like the Environmental Protection Agency or the US Department of Interior. And Congress, as you know, holds the purse strings in the US government. So they determine how much money is appropriated to the these agencies every year. And these are generally speaking must pass bills because you got to fund the government. You got to fund the operation and the government, whether it's the Environmental Protection Agency or the Internal Revenue Service or the Department of Veteran Affairs. All of these agencies need funding. Well, the committees in Congress to fund the US EPA and the Department of Interior and other agencies, the proponents of the biomass industry slipped in some language that's unrelated to the funding. They said that these agencies have to develop policies to reflect quote, the carbon neutrality of forest biomass. So Congress is legislating erroneous science. They are tying the hands of the agencies and saying, we're going to dictate the scientific terms. And we're going to insert this in a must pass bill. It is insidious. Over the past few years, they've succeeded. And we've been fighting it. There's a campaign. NRDC is involved, where we've been fighting this rider year after year. And our hope is to have it amended or removed in future years. But it's an uphill battle, because there are a lot of proponents of forest biomass in the US Congress.

Alasdair:

Is there much talk of development of bioenergy with carbon capture and storage or BECCS?

Sami:

Less so than in the UK. Right now, the focus has been around this carbon neutrality debate. And, in particular, you know, the industry looks at clean energy provisions, let's let's take Joe Biden's build back better policy and setting aside the question of whether it's likely to prevail or the prospects of succeeding there are there are clean energy provisions, not only in the build back better, but in other forms of legislation that are championed by true climate champs in the Congress. And these provisions typically involve incentives or subsidies for true clean energy like wind or solar, for example, there are federal tax incentives, production tax credits for wind companies or solar companies. The fear is that if you have a provision that says agencies should reflect the carbon neutrality of forest biomass, then under incentive programs, that might be construed as meaning forest biomass should also receive those subsidies. And that's a huge threat. That's exactly what we want to avoid.

Alasdair:

I wanted to come back to a point that you made earlier and I suppose your job, you set out your role at NRDC earlier as around carbon accounting. I wondered if you could say something about the carbon accounting rules, which have also allowed for, it's something that Duncan Brack at Chatham House has talked about, around the land use emissions being kind of lost in transfer essentially? It's probably better if you explain it. But I wondered if you could say something about about the carbon accounting rules, and what you might see as a way out of that in the future, and if you think there is one at all, in terms of actually being able to count true emissions in relation to biomass?

Sami:

I'll keep it at the high level, these forest accounting rules are holdovers from considerations, starting with the Kyoto Protocol back in 1990. So they are dated, they are not based on the current science, yet people continue to point to them. The second point is that they, as you said, fail to account for emissions. Why? Because they say that a company like Drax, doesn't have to count for the emissions out of its smokestack in the energy sector, in the power sector. Because those fuels come from a land based source, namely forests. And the accounting rule says, If you want to determine the emission that's coming out of the smokestack at Drax, you have to look at the forest. And you can then say okay, well, that forest was cut, and the reduction in carbon in the standing forest was such in such an amount. And that's where you actually do the calculations in the accounting, not at the smokestack. So Drax is in a position of saying we're zero, because that's what the accounting rules say. They say in the power sector, you can place a big zero in your ledger, and let the US look at its forest stocks. And you can see the nonsense associated with that approach. Because there's no systematic way that's been established to account for how much Drax is logging in the US in the first place. And then to transfer that into UK based policy to have them be responsible for it. So it's a fundal fundamental disconnect that was created. And again, it makes no sense the solution is to account for emissions at the stack, full stop. And if Drax wants to make promises about forest regrowth, or any other form of mitigation that occurs After you've cut the forest and burned it, let them make the promises. But you, in my opinion, need to show that that regrowth has occurred. So if they want to say, we're emitting, you know, 780 kilograms for every megawatt hour produced, and we're going to pay for that, but 20 years from now, we're going to show you that the forest that we cut has regrown. And maybe then we can get a credit. Sure, that approach might make sense, you know, get credit for the actual sequestered carbon that you produce, and you are responsible for, as a utility. You mentioned, well, they own some land, sure, they can document what they planted, when and how much it grew. You can do that in a forest, it's well established. But this nonsense about, well, we're gonna count at zero at the smokestack and just assume that it's being taken care of in the land use sector.

Alasdair:

So where do you think the the changes necessary are going to come from in order to get emissions countered that at stack at the power plant?

Sami:

I think it's going to have to be done either country by country, I don't see it being generated as a matter of, you know, international protocol. So in the US, we are strongly advocating that the starting point for regulation of the biomass industry, and for no analysis of its impacts in climate policies, the starting point is the stack and then you work back from that.

Alasdair:

My thanks to Sami Yassa, senior scientist at the Natural Resources Defense Council for his time, you can find links to his full research on BECCS as well as other information about the US congratulates work mentioned, published with this podcast and on our ELCI website. We'd also appreciate any feedback from our listeners, and we're very grateful for the positive feedback so far. And if there are new topics you would be interested in us looking into do feel free to get in touch with us through our website. Thanks for listening.