01. RESOURCE FLEXIBILITY

Both worldwide and in Greece, the vast majority of geothermal fields are characterized by medium enthalpy, water dominated resources. Turboden ORCs are particularly suited for the utilization of geothermal resources of such hydrothermal features.

Compared to conventional steam–based plants, Turboden ORCs have a definite thermodynamic advantage for resources at moderate temperatures (up to 150-200 °C). Furthermore Turboden ORCs can also utilize low-temperature resources (close to 90-100 °C), where electricity generation is neither technically nor economically feasible in steam cycle based plants.

02. SIMPLICITY & EASE OF OPERATION

In contrast to steam based plant where full time supervision by qualified operators is required, ORC plants are designed for automatic and continuous operation and can be operated even by unskilled personnel with weekly operation requirements as low as 3-5 hours.

Furthermore contrary to the complex and lengthy start stop procedures required for steam turbines, Turboden ORC follow a simple a short and simple process with the push of a button.

03. ZERO EMISSIONS

Geothermal fluids in Turboden ORC power plants are fully confined and re-injected through a closed loop process.

During the flashing process steam cycle based plants release non-condensable gases mainly composed of Carbon dioxide (CO2), but also with trace amounts of pollutants such as methane (CH4) and Hydrogen sulphide(H2S). The release of hydrogen sulphide is particularly problematic due to the resulting odor nuisance.

In binary power plants geothermal fluids are never flashed and only used as a medium for heating up and evaporating the working fluid; geothermal fluids per se are not evaporated and never make contact with the atmosphere before they are pumped back into the geothermal reservoir with all the containing minerals and dissolved gases

04. LOW MAINTENANCE | LONG OPERATIONAL LIFE

Even in standard power applications the maintenance of steam turbines is complicated and costly, requiring major overhauls at 5 year intervals. When employed in geothermal applications, steam systems require even more frequent maintenance due to turbine wear.

In contrast to flash and dry steam based plants where the geothermal fluid comes directly into contact with the turbine, geothermal power plants based on Turboden ORCs utilize the geothermal resource only as a medium for heating up the working fluid. The ORC’s turbine has no contact with the aggressive geothermal fluid which is confined inside the tubes of the heat exchangers.

Unlike steam the working fluid is non eroding and non corroding for valve seats tubing and turbine blades allowing for long operational life.

05. MODULARITY & SCALABILITY

Reservoir characteristics are seldom known with certainty at the early phases of a geothermal power project. The modularity of Turboden ORCs provides and effective way to deal with resource uncertainty, by allowing the expansion of generation capacity along with the development of the field.

The Turboden ORC based geothermal power plants INMIS designs and builds are tailored made to match specific resource conditions. Typical single unit sizes range from 1MWel to 8MWel, which are scalable for tailor made solutions for larger plants of 20MWel-30MWel.

06. RESERVOIR SUSTAINABILITY

In order to maintain a geothermal system and ensure the sustainable use of any geothermal resource the underground aquifer must be replenished at a rate similar to its use.

Turboden ORC plants are operating in a closed loop process where geothermal fluids after used for electricity generation, are injected back into the reservoir to be reheated and continue the sustainable cycle