Switzerland’s Scenarios for Land Based Mitigation – A Summary for Policymakers
We’ve identified a portfolio of land-based mitigation technologies and practices (LMTs for short) that stakeholders across Switzerland’s land-use sector consider to be the best suited to the Swiss context. Now, in a new report, we describe a range of possible ways these LMTs could become widely adopted (we call these scaling scenarios). We’re using these scenarios to develop a set of tools and methods that anyone can use to reliably estimate how much carbon could be stored in each of these scenarios. This can potentially inform everything from individual farmers’ soil management practices, to national climate plans and international climate negotiations.
The full scenario analysis for Switzerland can be found here, with key messages summarized in the sections below.
Switzerland’s Potential for BECCS
The most promising LMT is bioenergy with carbon capture and storage (BECCS), which has a technical potential of storing 5.1 Mt CO2 per year, double that of other LMTs. BECCS could be sourced from various biomass feedstocks, such as oil crops, sugar crops, forestry, and organic waste. However, there are concerns about competition for land with food production, as Switzerland is a net food importer. About half of the BECCS potential could be achieved without competing for biomass.
The combustion of biomass releases CO2 that was originally captured from the atmosphere through plant photosynthesis. To achieve negative emissions, an effective approach involves capturing this CO2 during combustion and storing it. In Switzerland, Bioenergy with Carbon Capture and Storage (BECCS) is gaining attention as a negative emission technology to compensate for remaining emissions by 2050. However, currently, no BECCS facilities in Switzerland capture CO2 from biomass combustion due to a lack of geological storage options.
Potential actors that could be coupled with Carbon Capture and Storage (CCS) are biogas plants that already use CO2 capturing technology to remove CO2 from biogas before entering the gas grid. Large-scale district heating plants utilizing bioenergy also seem suitable for BECCS. As BECCS primarily focuses on CO2 removal and does not offer additional benefits, it can be financed through carbon emission trading systems or direct payments for CO2 removal.
Regarding CO2 pricing, Switzerland currently has a tax on fossil fuels, but negative emissions cannot be sold within the cap and trade system. However, if negative emissions were accounted for, and the tax became applicable to all industries, BECCS would become more feasible. Alternatively, Switzerland may explore achieving negative emissions through compensatory projects in other countries.
Biochar
Biochar, a form of charcoal produced from biomass, has a theoretical potential to mitigate 2.2 Mt CO2 per year in Switzerland. However, competition with other LMTs for biomass, such as BECCS, could limit its implementation. The country has a sustainable biomass availability of 6.3 Mt per year, but only 3.4 Mt are currently utilized. Synergies between biochar production and BECCS could be explored to maximize efficiency.
As a Land-Based Mitigation Technology (LMT), biochar is used to enhance soil properties and serve as a long-term carbon storage method. Biochar's long turnover times in the soil, spanning decades to centuries, classify it as an LMT, making it an attractive option on voluntary carbon markets. Although some perceived risks exist, they are not considered significant concerns in recent literature on biochar application. Due to limited agricultural land in Switzerland and the country's priority to maintain food self-sufficiency, it is improbable that land suitable for food production will be allocated to biochar biomass production.
Competition for land and biomass would primarily occur on non-food production land, involving biochar, BECCS, and other material uses of biomass. While competition may arise between the direct application of harvest residues in the field and using them for biochar production, the latter could offer higher
Agricultural Management Practices
Agricultural management practices, such as reduced tillage and improved crop rotations, have a technical potential to sequester 2.7 Mt CO2 per year in Swiss agricultural soils. These practices are cost-effective and generally do not compete for biomass with other LMTs.
The measures to increase soil organic carbon content can be categorized into two main groups, both of which are already commonly employed by farmers in Switzerland. The first category focuses on augmenting the input of carbon into the soil, which facilitates the buildup of soil organic carbon. These measures encompass the use of cover crops, retaining residues on the field, returning organic residues and manures to the soil, cultivating deep-rooting crops, adopting improved crop rotations (including grass-clover leys), and implementing agroforestry techniques. The second category involves measures that decrease the turnover of existing soil carbon. One such measure is reduced tillage, though its impact on soil organic carbon remains a subject of debate, as it may either reduce soil organic carbon by disrupting soil aggregates or simply redistribute carbon within the soil profile.
Agroforestry and Peatland Management as Promising LMTs
Agroforestry, which involves planting trees alongside crops, could be a promising option to increase tree coverage in Switzerland without reducing agricultural land. It has the potential to sequester more carbon and has shown positive outcomes for those farmers already using this method.
While there are still some uncertainties and debates about the best approach, these land-based methods and practices offer potential solutions to address climate change and reduce CO2 emissions in Switzerland.
Conclusion
In general, Switzerland plays a pioneering role in negative emission technologies.
However, since land is limited there, all the LMTs in our portfolio are in competition with each other and with food production to some extent. Swiss policymakers are aware of this and are thinking about how to minimize conflicts and use each technique where it causes the least competition.
Biochar is a technology that can permanently store carbon and is available now, but it's too expensive to be competitive with current carbon prices. Additionally, there are some social concerns that need to be addressed before it can be widely used.
Swiss policymakers see the short-term potential and benefits of agricultural practices like reduced tillage and organic farming because they are cost-effective and have additional advantages. However, these practices are not permanent solutions, especially under future climate changes.
Modern agroforestry systems also have significant potential, and they might even make crop systems more resilient in a changing climate compared to monocrops. However, there's a lack of research on agroforestry in Switzerland, and there are no long-term trials to draw conclusions from.
