Krieg & Fischer Ingenieure GmbH

Krieg & Fischer Ingenieure GmbH is an engineering company with more than 30 years of experience in biogas technology.

We offer a full range of engineering and consulting services in the field of biogas, from preliminary study and plant design to commissioning and start up. Our services also include preparation of surveys, expert reports, insurance reports, studies and plant optimization measures, inspection of technical safety equipment and operator services and training courses – simply everything required in the biogas sector.

Krieg and Fischer Ingenieure GmbH provides customer specific, competent and innovative solutions, independently of equipment suppliers and subcontractors. With our special focus on safety technology, we reduce the impact on the environment through emissions and contribute to improving work safety.

The engineering office Krieg & Fischer Ingenieure GmbH is globally active in the biogas sector. Our experience includes more than 160 references, all over Europe, North & South America, Asia and Africa. These include simple farm-scale biogas plants for fermenting slurry, stable manure, energy crops and agricultural waste and also complex, multi-stage, industrial fermentation technologies for waste from the food industry, food leftover fermentation or organic waste fermentation plants.

We have particular expertise in the digestion of stillage from bioethanol production and residual materials from the sugar industry such as sugar beet pulp and vinasse.

If you are interested, we can provide an energy calculation and a cost assessment for your individual and tailor-made biogas plant free of charge. Contact us directly at


Tailor-made Solutions

Krieg & Fischer Ingenieure provides one-stop planning of biogas plants, from concept to commissioning, customised, competent, innovative and independent.

We tailor process technology to the input substrate and the local conditions. Starting from the input substrates, we develop the optimal and tailor-made system for our clients.

Our expertise includes substrate-specific pretreatment with the removal of unwanted materials or additional hygienization where necessary, as well as different fermentation processes such as one and two stages, mesophilic and thermophilic fermentation and wet and dry fermentation plants. We are a technology provider and deliver know-how. We do not supply turn-key biogas plants and are independent from any supplier, developing different solutions depending on the needs of our clients. Our choice is often high fermenters delivering optimal agitating properties to provide good value for money, but where appropriate, we also design flat fermenters with a gas storage roof or a plug-type flow system.


Over 30 years of experience

Our experience in biogas technology includes more than 160 references all over the world. Apart from references in Germany, our strategy is that we are a global service provider and we have a long experience with organising and dealing with projects all over Europe, North & South America, Asia and Africa. Our independency and experience means that we are very open-minded to deal with local companies on one hand and, on the other hand, we know all experienced suppliers from Germany or Western Europe who might be able in supplying equipment to specific projects.

The digester volume located on our plants ranges from 50 m³ to 22,000 m³; the CHP size from 27 kW to 8.4 MW electrical power. In our plants different input substrates are treated. We do not only possess experience with agricultural substrates such as slurry, manure, straw and other agricultural crop residues or various energy crops such as grass silage or maize silage but also with commercial waste such as kitchen waste, food leftovers, canteen waste, waste from the food industry, out-of-date foodstuffs from the retail trade, organic waste from industries such as fruit residue or market waste such as fruit and vegetable residues or municipal organic waste such as organic waste bins or green waste, etc.

Krieg & Fischer Ingenieure GmbH shares project experience in biogas in more than 20 countries, collaboration with reliable partners in 12 countries. Together with our partners we have created a global network, and are perfectly capable of constructing biogas plants which are adapted to the specificities of your country.

We offer a wide range of services, according to your specific needs:

  • Engineering tailor-made solutions for biogas plants: We provide complete engineering, from first concept to start up.
  • Tendering and Commissioning: Krieg & Fischer gives competent advice on obtaining equipment from experienced companies.
  • Construction management: We provide construction management, for both domestic and inter- national projects.
  • Start up: Whether to help you create a commissioning concept or help you monitor the biogas production and quality of your facility, we can start-up all kinds of fermentation and biogas plants.
  • Trainings: In addition to operator training, we also provide a platform for knowledge and experience transfer between search and teaching, operators and us as a planning engineering office.
  • Operator services: We aim to help you reduce your work load while simultaneously improving the safety of your biogas plant.
  • Optimization / Retrofits: We optimize existing biogas plants to increase the biogas yield and the energy efficiency.
  • Studies: Concept development and calculations – Feasibility studies – pilot studies.
  • Expert opinions: Evaluation – survey reports – arbitration opinions – opinions for insurance purposes

To know more about our services, please visit the Krieg & Fischer Ingenieure GmbH website.


  • Biogas & RNG Project Consulting
  • Biogas System Engineering
  • Biogas System Consulting
  • Construction Services
  • Training

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