/ our Projects
Case Studies & Impact
Energaia works at the intersection of research and implementation. These selected case studies highlight how our science translates into practical solutions for emissions reduction, sustainable energy, and environmental resilience.
Gasification of Sewage Sludge in Saxony
A Low-Emission Path Forward
Location: Saxony, Germany
Project Duration: 2023–2025
Partners: Robert Boyle Institute, Municipal Utility of Zittau, Technical University of Dresden
Lead Institution: Energaia gUG
Overview
Municipal sewage sludge is one of the most persistent waste challenges in Germany, both in terms of volume and climate impact. Traditional disposal pathways—incineration, landfill, or agricultural spreading—are under increasing regulatory and environmental pressure. With national policies targeting phosphorus recovery and stricter emissions limits, the need for innovative, low-carbon alternatives is urgent.
Energaia, in partnership with the Robert Boyle Institute and municipal stakeholders, launched a scientific pilot project to assess the environmental and technical viability of sewage sludge gasification as a scalable, climate-positive solution.
Energaia, in partnership with the Robert Boyle Institute and municipal stakeholders, launched a scientific pilot project to assess the environmental and technical viability of sewage sludge gasification as a scalable, climate-positive solution.
Challenge
High GHG emissions
from incineration and transport
Nutrient loss
and limited recovery in current processes
EU pressure
to reduce reliance on land application due to contamination risks (e.g., PFAS, heavy metals)
Need for regional
decentralized treatment options
Approach
The project focused on the deployment of advanced low-temperature gasification technology adapted to the properties of dewatered municipal sludge. Energaia's research unit developed a simulation model based on sludge composition, regional energy demand, and emission profiles.
Key activities included:
Techno-economic feasibility study comparing CAPEX/OPEX of gasification vs. mono-incineration
Life cycle assessment (LCA) including Scope 1–3 emissions and nutrient flow modeling
Pilot integration with an existing waste utility to test feedstock preprocessing and drying
Analysis of residual ash and char for phosphorus recovery potential
Stakeholder workshops with municipalities, utilities, and environmental agencies
Key Findings
GHG reduction potential: up to 74% lower net emissions compared to incineration
Energy recovery efficiency: 65–72% depending on feedstock conditioning
Biochar yield: ~10% of dry matter, with promising characteristics for soil application
Operational fit: Suitable for decentralized treatment plants serving populations under 100,000
Regulatory alignment: Compatible with new German Fertilizer Ordinance (DüMV) if post-treatment applied
Impact
The project demonstrated that gasification can be a technically feasible and environmentally advantageous alternative to conventional sludge treatment. Moreover, the integration of biochar production opens dual environmental benefits: clean energy and carbon sequestration.
This case study served as the basis for:
Biomass-to-Energy Innovation Hub in the Canary Islands:
Closing the Loop on Organic Waste
Location: Las Palmas de Gran Canaria, Spain
Project Duration: 2024–ongoing
Partners: Canary Islands R&D Agency, Incub8 Las Palmas, local agricultural cooperatives
Lead Institution: Energaia gUG
Overview
The Canary Islands face unique environmental challenges: high energy import dependency, increasing organic waste streams, and fragile agricultural soils suffering from degradation andwater stress. Despite significant biomass availability from palm pruning, fruit processing, and green waste, most organic residues are either landfilled or left to decompose.
Energaia launched a flagship initiative based out of Incub8, a public-private innovation hub in Las Palmas, to address these issues holistically. The project combines applied research, technology prototyping, and capacity building to promote circular bioeconomy strategies on the islands.
Energaia launched a flagship initiative based out of Incub8, a public-private innovation hub in Las Palmas, to address these issues holistically. The project combines applied research, technology prototyping, and capacity building to promote circular bioeconomy strategies on the islands.
/ Research
Challenge
Agricultural waste
is abundant but underutilized
Imported energy
accounts for over 90% of the islands’ supply
Soil degradation
limits crop productivity and resilience
Local innovation capacity
is fragmented and underfunded
Approach
Energaia developed a phased project architecture:
Phase 1: Biomass Mapping and Feasibility
Quantified annual biomass yield across targeted municipalities
Conducted feedstock quality assessments (moisture, ash content, calorific value)
Identified top candidates for thermochemical conversion (e.g., palm leaves, citrus pulp)
Phase 2: Technology Demonstration and Testing
Installed a mobile modular gasification prototype adapted for remote off-grid use
Integrated real-time sensors for emissions and yield monitoring
Produced biochar for initial field trials in volcanic soils
Phase 3: Knowledge Hub and Training
Hosted workshops with agricultural cooperatives, students, and local policymakers
Developed open-source design templates for scalable micro-plants
Built partnerships for policy support and follow-on funding from regional green transition programs
Key Results (to date)
3 viable biomass streams confirmed for energy and biochar production
First biochar-amended test plots show 18% increase in soil water retention
Emissions from pilot unit met EU Stage V non-road standards
Increased stakeholder engagement, including requests for replication in Fuerteventura and La Palma
Impact
The Biomass-to-Energy Innovation Hub has created a real-world testbed for climate resilience, waste valorization, and decentralized energy systems. It bridges public needs (clean energy, soil restoration) with scientific solutions, and showcases the kind of applied impact that a research institute like Energaia can drive.
This case study is now being expanded into: