The Energy Collective Group

This group brings together the best thinkers on energy and climate. Join us for smart, insightful posts and conversations about where the energy industry is and where it is going.

9,748 Subscribers

Article Post

Closing Another Technology Door?

The National Oceanic and Atmospheric Administration have now released 2017 temperature data, showing the year to be the third warmest on record, but also the warmest in a non-El Nino year. The story resulted in a flurry of articles across the media world.

Temperature anomaly to 2017

The New York Times published a story which attempted to summarize current efforts to reduce global emissions. Their take on the issue is akin to the Hans Christian Andersen parable, The Emperor’s New Clothes, where the Emperor was tricked into believing that his new clothes were the finest available, when in fact he was wearing nothing at all. The New York Times notes;

Inveigled by three decades of supposed diplomatic progress — coupled with falling prices of wind turbines, solar panels and batteries — the activists, technologists and policymakers driving the strategy against climate change seem to have concluded that the job can be done without unpalatable choices. And the group is closing doors that it would do best to keep open.

The choices they are referring to are nuclear, various forms of carbon capture and storage (CCS) and geoengineering. Readers of my posts over many years, and my recent book, Putting the Genie Back will recognise my particular passion for the second on this list, the role of CCS. As I see it, no matter which way you do the maths, the climate problem doesn’t resolve itself without some form of large scale carbon capture. Building carbon capture and storage capacity offers a further option which gets little attention today but may well be vital for the next generation; the prospect of climate restoration, or removal of additional quantities of carbon dioxide from the atmosphere in the 22nd century to bring the temperature back towards pre-industrial levels.

But as if on cue with the NYT story, researchers from the Potsdam Institute for Climate Impact Research (PIK) published a paper in Nature Climate (subscription required) which questions the implementation of BECCS in emissions mitigation. BECCS, or bio-energy with CCS, is conventional CCS applied on power plants operating with a biomass feedstock as their energy source. The geologically stored CO2 has been removed from the atmosphere via the carbon contained in the biomass. The Guardian also published a similar story.

BECCS plays a critical role in many climate models and the scenarios developed with them, in that it offers a route to remove emissions from ongoing use of fossil fuel in sectors where the technology pathway for zero emissions either doesn’t exist or is in its infancy. Aviation is one such example; there is no line of sight today to alternative fuels or means of propulsion for aviation, except for a drop-in hydrocarbon substitute produced via a biofuel route. A large-scale alternative to current aviation fuel or a brand-new propulsion system for planes will take decades to fully develop and deploy.

BECCS is also used extensively in the scenarios published as part of the IPCC 5th Assessment Report and are expected to feature in the IPCC Special Report on 1.5°C, coming out later this year.

The concern raised by the PIK researchers is that large scale growth of suitable biomass for power stations would disrupt other earth systems, breaching various planetary boundaries such as freshwater availability. They conclude that socio-economic pathways requiring substantial BECCS bear the risk of triggering potentially irreversible changes in the Earth system through extensive land-use change, water use, alteration of biogeochemical flows and compromising biosphere integrity.

While it is important to fully understand the impact and risks of various energy pathways, simply removing yet another mitigation option from the table isn’t helpful for a discussion that is running very short of possible routes forward. The broader use of biomass for energy, together with nature based solutions, including reforestation, changes in agricultural practices and restoring degraded land is very likely to figure in our energy future, so should be looked at more holistically. For example, looking at various practices around the world today offers great potential, when comparing the range of crop yields from what is otherwise similar land. Introducing best practices more widely could allow significant scope for bio-energy production without impairing other systems.

Original Post

Content Discussion

Rex Berglund's picture
Rex Berglund on February 7, 2018

The US DOE estimates a billion dry tons of biomass can be grown each year w/out adverse environmental impact. Given that Allam-cycle tech. using gasified biomass could provide a BECCS functionality, that would be an upper limit of 1.75 gigatons of Carbon Dioxide Removal/year in the US.

Going forward, experiments to farm the oceans for biomass are under way. This initiative by ARPA-E will engage PNNL to make biocrude from the biomass produced, but that could potentially be shifted to a focus on syngas creation providing another path for BECCS.

Engineer- Poet's picture
Engineer- Poet on February 7, 2018

The US DOE estimates a billion dry tons of biomass can be grown each year w/out adverse environmental impact.

Note that that’s just the biomass which can be taken off the land.  This is only a fraction of the carbon in play.

Given that Allam-cycle tech. using gasified biomass could provide a BECCS functionality, that would be an upper limit of 1.75 gigatons of Carbon Dioxide Removal/year in the US.

With improved management aimed at increasing soil carbon inventories, the net amount might be much greater than this (at least in the short term).

Perhaps this is a way to reduce the net impacts of things like palm-oil plantations, by taking the non-oil biomass of the fruit, dropped leaves and dead trees and storing it as biochar in the soil.

Engineer- Poet's picture
Engineer- Poet on February 7, 2018

no matter which way you do the maths, the climate problem doesn’t resolve itself without some form of large scale carbon capture.

Indeed it does not.  But how?

Building carbon capture and storage capacity offers a further option which gets little attention today but may well be vital for the next generation; the prospect of climate restoration, or removal of additional quantities of carbon dioxide from the atmosphere in the 22nd century to bring the temperature back towards pre-industrial levels.

This is hard to reconcile with the inconvenient truth that recent projects aimed at proving the concept have failed to meet their goals.  Some of the failures, like the Kemper coal-gasification plant, have been spectacular.  Going from “need to” to “have a way to” to “have an economical, scalable way to” is a path fraught with perils, and nobody has yet proven that anyone can actually get there.

There’s the further inconvenient truth that most of the “sequestration” schemes are aimed at things like tertiary oil recovery, which extracts more carbon as oil than is put down as CO2 on a volume/volume basis.

Rex Berglund's picture
Rex Berglund on February 8, 2018

Yes since we have twice as much ocean as land, aquacultured energy crops have a distinct advantage in scalability.

ARPA-E gave Marine Bioenergy $2M for the kelp farming piece of the project, the concept is a grid of air hoses and flotation buoys that can raise and lower the kelp once a day for sunlight and nutrients, sounds simple enough. Also, submarine drones for transport. Perhaps rather than converting kelp to fuel, a simpler sequestration strategy is to just reduce it’s buoyancy and let it sink to the bottom.

Glad you mentioned biochar, I thought that was a great idea till the NAS published their CDR paper and claimed there was insufficient proof biochar would last long enough in the soil to be considered permanent. So, I was heartened to find this recent study which found biochar “displayed a mean residence time > 100 years in the field, which is the threshold for permanent removal in C sequestration projects.”

Engineer- Poet's picture
Engineer- Poet on February 8, 2018

You’d think the mere existence of terra preta do indio after all these centuries would be proof enough.

Rex Berglund's picture
Rex Berglund on February 8, 2018

I know right? In the case of the CDR paper, NAS relied heavily on research by Gurwick et al which was a survey of studies covering over 300 papers. Although it didn’t rule out biochar’s long term sequestration of carbon in soil, the conclusion was that there wasn’t enough evidence to support that. Hopefully NAS will revisit the issue and update its findings.