Geothermal EXERGY - Efficient and tailor-made Organic Rankine Cycle geothermal binary power plants

“In only 6 years we achieved the second largest ORC binary geothermal fleet worldwide”

Geothermal resources are one of the most secure and stable among renewables for reliable base-load energy production.
Today the total installed capacity worldwide is 14,060 MW, with USA, Philippines, Indonesia and Turkey leading the way.

Growing demand for electrical power production from geothermal resources at medium-low temperatures has created a promising and evolving market for ORCs that have proven to be the best power generating solution in these cases.

With our patented Radial Outflow Turbine technology, EXERGY offer efficient and tailor-made Organic Rankine Cycle (ORC) geothermal binary power plants and today counts over 370 MWe of geothermal power installed or under construction in its portfolio.

EXERGY’s ORC systems can be applied in diverse resource conditions:

LOW/MEDIUM ENTHALPY
LOW/MEDIUM ENTHALPY
HIGH ENTHALPY
HIGH ENTHALPY
COMBINED CYCLE (FLASH AND BINARY)
COMBINED CYCLE (FLASH AND BINARY)
WELL-HEAD GENERATION
WELL-HEAD GENERATION

EXERGY’s ORC systems are available from small 1 MW modular units to tailor-made plants up to 50 MW.

PORTFOLIO
PORTFOLIO
371,5MW
PLANTS
PLANTS
24
AVERAGE PLANT SIZE
AVERAGE PLANT SIZE
15,4MW
AVERAGE AVAILABILITY
AVERAGE AVAILABILITY
99%
OIL SAVED  toe/y 
OIL SAVED toe/y 
467090

Thanks to the simpler design and specific configuration of the ROT technology our ORC geothermal plants can offer several advantages:

STANDARD MECHANICAL DESIGN FOR EACH TURBINE FRAME
STANDARD MECHANICAL DESIGN FOR EACH TURBINE FRAME
  • The fluid dynamic design of each turbine is optimized in order to reduce supply time, guaranteeing maximum efficiency without need for mechanical redesign of the turbine
MULTIPLE PRESSURE ADMISSIONS POSSIBLE ON A SINGLE DISK
MULTIPLE PRESSURE ADMISSIONS POSSIBLE ON A SINGLE DISK
  • 20% more power than a single level system with a simple configuration
  • Suitable for low temperature heat sources, as low as 90° C
UP TO 7 STAGES ON A SINGLE-DISK TURBINE
UP TO 7 STAGES ON A SINGLE-DISK TURBINE
  • Extreme flexibility for changing geothermal fluid conditions, in terms of flow, temperatures and constituents

EXERGY’s ORC systems are available from small 1 MW modular units to tailor-made plants up to 50 MW.

EXERGY’s ORC systems are available from small 1 MW modular units to tailor-made plants up to 50 MW.

Binary geothermal power plants have the possibility to feature multi-pressure-level cycle systems. This cycle configuration offers a significant increase in the power output and in the cycle efficiency. Technologically advanced multi-pressure-level geothermal binary systems traditionally available on the market require at least one turbine per pressure level. The EXERGY Radial Outflow Turbine, thanks to its unique single disk and multi-stage configuration, allows multiple pressure level cycles to be expanded on a single-disk overhung turbine.

The geothermal fluid flows through the first sequence of HIGH pressure heat exchangers, transferring heat to the organic fluid. This organic fluid vaporizes and flows into the HIGH pressure turbine Inlet. Then the geothermal fluid flows through the second sequence of LOW pressure heat exchangers, vaporizing the organic fluid, which is then admitted into the LOW pressure turbine Inlet. The EXERGY Radial Outflow Turbine (ROT), fed by HIGH and LOW pressure organic fluids, drives a generator to produce electrical power. The geothermal fluid is then re-injected back into the ground and the cycle continues.

Some geothermal binary plants, downstream the ORC cycle, release exhaust non-condensable gases at high pressure and temperature no longer usable in the ORC cycle. EXERGY has designed and developed the NCG expander unit in order to utilise this residual gas flow with the maximum efficiency, before its discharge into the atmosphere.

The NCG expander is a compact plug-n-play unit, containing a turbine that expands the non-condensable gases exiting the ORC cycle, to produce additional electrical energy. Each NCG unit is designed to improve the plants’ performances and profitability, and at the same time, reduce the environmental impact of the plant. When the NGC is supplied in plants with high NCG volumes it can increase up to 5% the plant’s efficiency.

COMPACT AND SIMPLE DESIGN
COMPACT AND SIMPLE DESIGN
  • Easy and fast installation with a plug-n-play solution
  • Shippable in single units
IN HOUSE DESIGN
IN HOUSE DESIGN
  • Perfect match with the performance needs and design details of the plant