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RESAIL - Reliable and economic integration of the Swiss Federal Railways to the energy strategy
Item type: Report
Bellè, Andrea; Marinakis, Adamantios; Fuchs, Alexander; et al. (2026)
This study supports SBB’s long-term energy strategy in the context of the Swiss and European energy strategies, relying on massive penetration of variable renewables and significant increase of electricity demand. As a major electricity consumer with a dedicated 16.7 Hz traction-power system, SBB is exposed to increasingly volatile and seasonal wholesale price dynamics, winter scarcity risks, and the cost impacts of transmission tariffs applied to exchanges with the public 50 Hz grid. At the same time, SBB owns a portfolio of hydropower assets, including run-of-river, reservoir, and pumped-storage plants, that provide flexibility and can partially hedge market exposure.
The central objective is to derive robust insights and recommendations for SBB’s future investment and procurement choices under the light of the ongoing energy transition. To this end, the study links system-level transition pathways at Swiss and European level to SBB-specific decision-making. A harmonized European–Swiss scenario framework is used to simulate energy system dispatch and to generate hourly energy market price trajectories for snapshot years 2030, 2040, and 2050. These scenario-based prices are then treated as exogenous inputs for an SBB-focused optimization model operating under a price-taker assumption.
SBB’s interaction with the external system is represented through a three-node model: (i) an SBB node containing demand, SBB-owned generation, and potential new investments; (ii) a copperplate representation of the Swiss transmission grid to capture tariff exposure, in particular energy-based (working) and capacity-based (peak power) tariff components; and (iii) a Swiss market node through which electricity and other carriers can be purchased or sold at the scenario prices. The planning model determines cost-optimal investment pathways while respecting SBB-specific operational constraints and a winter
self-sufficiency requirement formulated over the period October to March. Importantly, this requirement is interpreted as an "ability-to-cover" constraint (domestic production and/or long-term contracted volumes must cover at least a target share of winter demand), not as a self-consumption constraint, as electricity can still be traded on the market.
Across scenarios, the results highlight that SBB’s optimal strategy is dependent on external price dynamics, tariff exposure, and the chosen level of winter self-sufficiency. Higher seasonal scarcity and stronger peak-tariff signals increase the value of flexibility and of measures that reduce peak imports. Conversely, scenarios with more moderate winter prices and higher system-wide flexibility reduce the economic pressure to build additional dedicated capacity, although security-of-supply objectives can still justify investment. The analysis also shows that winter self-sufficiency is a binding strategic choice: tightening the target can substantially alter the cost-optimal portfolio and requires deliberate trade-offs between cost and security-of-supply.
Overall, the scenario comparison suggests a potential "low-regret" pathway. Early action should prioritize measures with strong performance across all futures: sustained efficiency measures, market procurement to diversify exposure (for example, long-term renewable PPAs such as wind to mitigate winter risk), and timely deployment of comparatively low-cost solar where it can contribute to reducing net imports and supporting winter self-sufficiency targets. More capital-intensive or highly path-dependent commitments, especially those driven primarily by extreme scarcity outcomes, can be triggered later as the transition trajectory, tariff design, and market conditions become clearer. This approach aligns with the broader Swiss energy strategy by combining near-term efficiency and renewable expansion with prudent management of security-of-supply objectives.
X:Map: annotation and visualization of genome structure for Affymetrix exon array analysis
Item type: Journal Article
Yates, Tim; Okoniewski, Michał J.; Miller, Crispin J. (2008)
Affymetrix exon arrays aim to target every known and predicted exon in the human, mouse or rat genomes, and have reporters that extend beyond protein coding regions to other areas of the transcribed genome. This combination of increased coverage and precision is important because a substantial proportion of protein coding genes are predicted to be alternatively spliced, and because many non-coding genes are known also to be of biological significance. In order to fully exploit these arrays, it is necessary to associate each reporter on the array with the features of the genome it is targeting, and to relate these to gene and genome structure. X:Map is a genome annotation database that provides this information. Data can be browsed using a novel Google-maps based interface, and analysed and further visualized through an associated BioConductor package. The database can be found at http://xmap.picr.man.ac.uk. © 2007 The Author(s).
Agent-based models for assessing clean energy adoption policies
Item type: Other Journal Item
Caterina, Croci (2026)
Search for decays of the 125 GeV Higgs boson into a photon and a ϕ, ω or D∗0 meson
Item type: Master Thesis
Pedemonte Bernat, Martí (2023)
A search for the exclusive decays of the Higgs boson to a photon and either a ϕ(1020), ω(782) or D∗(2007)0 meson is presented. These decays have been suggested as a probe of the Higgs boson couplings to light quarks and as a test of potential deviations from the Standard Model prediction in these flavour interactions. The analysis is performed with a pp collision data sample corresponding to an integrated luminosity of 39.54 fb−1 collected at √s =13 TeV with the CMS detector at the Large Hadron Collider (LHC) in 2018 during Run 2. Four decay channels are explored: H ϕγ with further ϕ π+π−π0, H ωγ with further ω π+π−π0, H D∗0γ with further D∗0 D0π0/γ, D0 K−π+ and H D∗0γ with further D∗0 D0π0/γ, D0 K−π+π0. Estimated upper limits at a 95% confidence level on the branching fractions of the four Higgs boson decay modes were obtained. These are 1.969 × 10−2, 2.867 × 10−3, 7.403 × 10−3 and 1.268 × 10−2, respectively.
On an online spanning tree problem in randomly weighted graphs
Item type: Journal Article
Remy, Jan; Souza, Alexander; Steger, Angelika (2007)
This paper is devoted to an online variant of the minimum spanning tree problem in randomly weighted graphs. We assume that the input graph is complete and the edge weights are uniformly distributed over [0,1]. An algorithm receives the edges one by one and has to decide immediately whether to include the current edge into the spanning tree or to reject it. The corresponding edge sequence is determined by some adversary. We propose an algorithm which achieves $\mathbb{E}[ALG]/\mathbb{E}[OPT]=O(1)$ and $\mathbb{E}[ALG/OPT]=O(1)$ against a fair adaptive adversary, i.e., an adversary which determines the edge order online and is fair in a sense that he does not know more about the edge weights than the algorithm. Furthermore, we prove that no online algorithm performs better than $\mathbb{E}[ALG]/\mathbb{E}[OPT]=\Omega(\log n)$ if the adversary knows the edge weights in advance. This lower bound is tight, since there is an algorithm which yields $\mathbb{E}[ALG]/\mathbb{E}[OPT]=O(\log n)$ against the strongest-imaginable adversary.