AAT Commissions the Largest Biogas Plant in the Baltics (Saaremaa, Estonia)
TAHULA, ESTONIA — AAT Biogas Technology is proud to announce that its landmark biogas plant in Estonia has successfully passed all commissioning and startup operations. The facility is now fully operational, delivering its first commercial biomethane ahead of schedule in 2026.
Located in Tahula village (Saaremaa municipality), this state-of-the-art facility is currently the largest biogas plant in the Baltics. It represents a massive leap forward for the region’s renewable energy sector and circular economy.
The scale of this Estonian biogas project showcases AAT’s advanced engineering. To ensure maximum operational reliability and high-efficiency methane yield.
Plant Configuration & Digester Volume
The infrastructure is divided into two parallel processing lines, each consisting of:
- 1 Mix Tank for substrate homogenization
- 3 Digesters for primary anaerobic digestion
- 1 Post-Digester for maximum gas extraction
Key Technical Data: The plant operates a total of 6 digesters, with a volume of 3,880 m³ each. (Dimensions: Ø 26m x 8 m), providing the massive retention capacity needed for stable biological processes.
Sustainable Agricultural Waste-to-Energy Processing
As a major environmental milestone for Saaremaa, the plant is engineered to process nearly 800 tons per day of locally sourced solid and liquid agricultural waste.
By recycling organic waste streams, AAT’s technology reduces greenhouse gas emissions from local farming while producing clean, scalable energy. The primary feedstocks include:
- Animal Manure: Cow and pig manure
- Agricultural Residuals: Feed rests and grass silage
- Industrial Organic Waste: Flotation sludge and whey
Biomethanation and Bio-Fertilizer Output Capacity
The successfully commissioned facility delivers high-performing environmental and economic metrics, converting raw waste into high-value green energy commodities:
- Raw Biogas Production 1,460 Nm³/h
- Biomethane Equivalent 880 Nm³/h (after upgrading)
- Organic Fertilizer Production 756 t/d (nutrient-rich digestate)
Grid-Ready Biomethane Upgrade
The raw biogas generated on-site is continuously upgraded into high-grade biomethane. This green gas is ready for injection into the national gas grid or for use as a sustainable transport fuel (Bio-CNG/Bio-LNG).
Closing the Loop with Eco-Friendly Fertilizer
In addition to clean energy, the plant outputs a high-quality organic fertilizer. This digestate is returned to local Estonian farmers, replacing synthetic fertilizers and enriching the soil via a perfect circular economy loop.
Partner with AAT for Advanced Biogas Solutions
The successful launch of the Saaremaa project reinforces AAT’s position as a leading international developer of industrial-scale biogas plants in Europe. From engineering and design to commissioning and startup, AAT delivers reliable, high-yield waste-to-energy solutions.
Are you looking to develop a sustainable biogas or biomethane project? Contact AAT Biogas experts today to learn more about our proprietary technology.
