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Geothermal
currently being operated with a very special design that is mostly called as triple flash + binary combined cycle technology in the literature . Geothermal brine , gathered from various production wells , are flashed or separated at three different levels to generate 60 MWe electricity via steam turbines . High pressure ( HP ) turbine exhaust steam is also utilised to generate 20 MWe more electricity via utilising binary turbines using ORC cycle . KZD2 Geothermal Power Plant has one of the highest capacity in Turkey with 80 MW of installed power and among the most important geothermal power plants in the world . All the electricity is sold via feed-in tariff mechanism . There are 12 production wells in operational conditions . Average temperature and pressure at wellheads are 178 ° C and 10.65 barg respectively .
Enhanced flexibility through integration of thermal energy storage GeoSmart innovations for KZD2 includes integration of a latent thermal energy storage that would increase the flexibility of the power plant by storing the heat from the brine after the steam separation . This latent heat storage will use Phase Change Material ( PCM ) to store the energy as latent heat at an almost constant temperature . During periods with low demand , energy will be stored in the storage to be released at a later stage when the demand is higher . As this approach does not influence the flow condition at the wellhead , critical infrastructures will be unaffected under variable energy generation .
Removal of scaling constraints to allow higher utilisation of energy from geothermal brine At KZD2 site , the geothermal brine is extracted from deep underground and arrives at the production unit at 165 ° C and 7.85 bar . It is then expanded through 3 separators to 105 ° C and 1.4 bar ; the steam produced feeds three steam turbine stages and exhausted steam from the HP ( high pressure ) turbine feeds binary unit heat exchangers ( ORC cycle ) which are all producing 80 MWe . The limiting constraint , to fully utilising the thermal energy of the brine , is often the need to reinject geothermal brine at high enough temperature to prevent silica b ) Integration of flexible Organic Rankine Cycles ( ORC ) that can cope with variations in needs in the electricity markets and c ) innovations that would help suppliers extract more heat from the brine to help supply more heat during high demands .
These innovations are being designed to be demonstrated in working geothermal plants with different flexibility needs - low enthalpy ( Insheim , Germany ) and high enthalpy ( Kizildere , Turkey ).
GeoSmart demonstration Zorlu Enerji , one of the partners in consortium , is providing the high enthalpy demonstration Kızıldere- II geothermal power plant for the GeoSmart project . Kizildere II ( KZD2 ) geothermal power plant is
The GeoSmart Consortium is made up of 19 international collaborators , led by TWI . www . heat-exchanger-world . com Heat Exchanger World October 2022
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