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ActiveOctober 2026 – September 2028

Waste2X

Biowaste valorisation coupled to Power-to-X

Upgrading biogas to grid quality means stripping out 35–45 vol% CO₂, a stream that is already captured, biogenic, and concentrated. Almost all of it is vented. Hydrogenating that CO₂ instead lifts a plant's methane output by roughly 60% from feedstock it already handles, without a single additional hectare of land.

Host
Technical University of Munich
Funding
Alexander von Humboldt Research Fellowship
Role
Project lead
Period
October 2026 – September 2028
01The system

Every pathway, held open at once

This is the project's own system schematic, drawn live. A superstructure keeps all candidate routes in play so that optimisation, not the engineer's prior, decides which ones a given case should build.

SupplyPre-conversionConversionEnd useWind energyElectricitySolar energyElectricityAgricultural wasteBiomassAnimal manureBiomassElectrolyzerH₂ + O₂Air separationN₂Anaerobic digestionCH₄ + CO₂GasificationSyngasAmmonia synthesisNH₃Methanol synthesisCH₃OHMethane synthesisCH₄Power plantElectricity + heatLivestock sectorFertiliser, heatResidential sectorHeat, powerIndustry sectorsFeedstock, heatTransportFuel

Every line is a pathway the optimiser may select. Hover or focus any unit to trace its full chain, upstream to the feedstock, downstream to the end use. Click to pin it.

  • Electricity
  • Feedstock & CO₂
  • Hydrogen & fuels
01Supply
  • Wind energy · Electricity
  • Solar energy · Electricity
  • Agricultural waste · Biomass
  • Animal manure · Biomass
02Pre-conversion
  • Electrolyzer · H₂ + O₂
  • Air separation · N₂
  • Anaerobic digestion · CH₄ + CO₂
  • Gasification · Syngas
03Conversion
  • Ammonia synthesis · NH₃
  • Methanol synthesis · CH₃OH
  • Methane synthesis · CH₄
  • Power plant · Electricity + heat
04End use
  • Livestock sector · Fertiliser, heat
  • Residential sector · Heat, power
  • Industry sectors · Feedstock, heat
  • Transportation sector · Fuel
02Objectives

What the project sets out to answer

Waste2X integrates biowaste valorisation with Power-to-X to close the carbon loop on residues that are already being collected. Anaerobic digestion and gasification turn agricultural waste and manure into biogas and syngas; renewable electricity drives electrolysis; and the biogenic CO₂ that a conventional upgrading plant vents is instead hydrogenated into synthetic fuels. The project builds the plant-wide models, the optimisation and the techno-economic case that decide which of those pathways is worth building.

  1. 01

    Model the whole system, not the unit

    Plant-wide mass and energy balances across digestion, gasification, electrolysis and synthesis, at MW to GW scale, so the interactions between units are visible rather than assumed away.

  2. 02

    Search the superstructure

    Multi-objective optimisation over every candidate pathway at once, returning the trade-off front between cost, efficiency and carbon rather than a single point design.

  3. 03

    Put biogenic CO₂ to work

    Treat the digester's CO₂ as a feedstock rather than a waste, and quantify what that is worth against the cost of the hydrogen needed to convert it.

  4. 04

    Test commercial viability

    Techno-economic and exergoeconomic assessment under realistic price and policy scenarios, with the sensitivity ranking that shows which assumptions the case actually turns on.

Units in the superstructure
16

Four stages, from feedstock to end use

Candidate pathways
28

Every link the optimiser may select

Product routes
4

Hydrogen, methane, methanol, ammonia

More methane per tonne
~60%

From hydrogenating the CO₂ already separated

03Foundations

What it builds on

Waste2X is not a standing start. Each strand of it comes out of work already published or delivered.

  • Allam cycle and Power-to-X integration (Ph.D., Aalborg University)
  • CO₂ capture, compression and transport from biomass CHP
  • Offshore infrastructure repurposing for renewable methane
  • Superstructure optimisation of power-to-methanol with hybrid SOEC

Check the premise yourself

The claim that hydrogenating a digester’s waste CO₂ lifts gas output by roughly 60% is not rhetoric, it falls out of the biogas composition. The biowaste calculator runs that balance for any feedstock and throughput you like.

Open the calculator
Units in the superstructure
16
Candidate pathways
28
Conversion stages
4

Working on something adjacent?

Waste2X runs to 2028 and is open to industrial partners, data collaborations and co-supervised students.

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