kIEFER TEK LTD, specializes in design, authorization, installation, operation and management of biogas plants for the generation of electricity and heat power.

Biogas is produced by anaerobic digestion mainly of livestock waste (waste water from pig farms, cattle farms), agro-waste and wastewater, as well as municipal organic waste. It consists of 65% methane and 35% carbon dioxide and can be exploited by feeding internal combustion engines, gas burners or gas turbines in order to produce electricity and heat. The greatest advantage of a biogas plant is the very low (up to zero) cost of raw materials in contrast to the gain from its products.

Authorization of Biogas Plants

The erection of each new biogas plant requires a number of permits. Because of its complexity, the biogas technology is a fairly new industrial application in many countries and particularly in Greece there is not enough experience in the evaluation of biogas plants.

In any case, the design process requires expertise, since a wide range of different technologies has to be used. For this reason we support our customers with complete technical documentation, which is essential for the construction of the Project.

Project design

The project design includes the detailed dimensioning of the biogas plant. During the development process takes place the definitive selection of the installation materials of the Biogas plant in order to minimize the probability of any authorization modification.

  • receipt and storage of the input material
  • preparation of the raw material
  • fermentation/ gas production
  • storage and disposal of the produced material
  • gas accumulation
  • gas preparation
  • gas production
  • machine measurement and control

Biogas technology

Due to the continuous communication with our suppliers, our technologyis always updated according to the international standards.

The Biogas technology used by kIEFER is based on a continuous two-stage process. Normally, three tanks are required: a digester, a secondary digester and a digestate storage tank. In cases where the percentage of the used liquid manure exceeds 30%, single-stage plants can be constructed. Then the installation consists of a digester and a "cold" secondary digester, which is used, at the same time, as a storage tank for the digested substrate.


The atmosphere inside the digester contains almost no oxygen. Inside the tank there is a mesophilic constant temperature (40-42 °C) and a neutral pH (6,7- 7,5). The plants are equipped with standard components, depending on their needs. The basic parameters for the evaluation of biogas plants are the retention time and the organic loading rate. Taking into account these parameters, we ensure that the owner can operate the plant with economic success.


Suitable as feedstock are basically all the organic materials. These can be food industry waste, organic fertilizers or renewable plant resources from farms. Because of the law’s priority to renewable energy sources, the German owners of biogas plants in previous years used largely renewable plant resources and liquid manure.

Return on investment

In order to achieve the optimum return, we evaluate the project in technological, economic and ecological terms.

The calculations are based on the characteristics of the raw material that is available in the plant area and the availability of agricultural land for the production of the raw material.