4TH INTERNATIONAL CONFERENCE4TH INTERNATIONAL CONFERENCE ““ENERTECH 2009ENERTECH 2009””ATHENSATHENS,  2,  233‐‐2244 OCTOBEROCTOBER 20020099

COGENERATION OF HEAT & POWER (CHP) COGENERATION OF HEAT & POWER (CHP) 

FROM MEDIUM ENTHALPY GEOTHERMAL FLUIDSFROM MEDIUM ENTHALPY GEOTHERMAL FLUIDS

M. FYTIKAS & M. PAPACHRISTOUM. FYTIKAS & M. PAPACHRISTOU

Medium Enthalpy Geothermal Potential in GreeceMedium Enthalpy Geothermal Potential in Greece

TemperatureTemperature = 90= 90‐‐150150°°CC

UtilisationUtilisation: CHP & Direct Use (heating, cooling, industrial : CHP & Direct Use (heating, cooling, industrial 

and agricultural use, etc) and agricultural use, etc) 

LocationLocation: Sedimentary basins of Northern Greece & North: Sedimentary basins of Northern Greece & North‐‐

Central Aegean islands (Samothrace, Lesvos, Chios etc) Central Aegean islands (Samothrace, Lesvos, Chios etc) 

NorthNorth‐‐Eastern GreeceEastern Greece

Aristino (Alexandroupolis) geothermal fieldAristino (Alexandroupolis) geothermal field

T>50T>50ººC at 200m and C at 200m and T>86T>86ººC at 360mC at 360m

Well AAWell AA--1:1: 72.372.3ººC at 360m (geothermal gradient=160C at 360m (geothermal gradient=160ººC/km)C/km)

Well AAWell AA--1P:1P: 5151ººC at 216m (geothermal gradient =180C at 216m (geothermal gradient =180ººC/km)C/km)

Well AA3:Well AA3: 86.886.8ººC at 340m (geothermal gradient =210C at 340m (geothermal gradient =210ººC/km)C/km)

Flow rateFlow rate :: 150m150m33/h/h

Evros BasinEvros Basin

XanthiXanthi‐‐Komotini BasinKomotini Basin

Nea Kessani geothermal field

The maximum temperature The maximum temperature registered within the (relatively registered within the (relatively shallow) wells is shallow) wells is 8282°°CC..

The main hot reservoir is located The main hot reservoir is located at shallow depth 150at shallow depth 150‐‐400m with 400m with temperatures between 75 temperatures between 75 ‐‐80 80 °°C.C.

At At 1000m1000m temperature may reach temperature may reach up to up to 110 110 °°CC

Eratino Eratino –– ChrysoupolisChrysoupolis

––Intense geothermal anomaly Intense geothermal anomaly with gradient between with gradient between 8080‐‐100 100 ººC/kmC/km..––Temperatures of 60.9 Temperatures of 60.9 ººC at C at 430m and 69.7 430m and 69.7 ººC at 530m C at 530m were recorded in exploration were recorded in exploration boreholesboreholes––Artesian flow rate 200 mArtesian flow rate 200 m33/h, /h, 75oC from 700m deep well75oC from 700m deep well––Temperature of Temperature of 122 122 ººC at C at 1377m 1377m were recorded in a were recorded in a exploration well (Nexploration well (N‐‐1P), 1P), average gradient 78average gradient 78ººC/km.C/km.

Nestos BasinNestos Basin

Strymonikos GulfStrymonikos Gulf

Akropotamos (Kavala) geothermal fieldAkropotamos (Kavala) geothermal field

AKP‐1: Τ= 83 °C at 270 m; flow rate 150 m3/hAKP‐3: Τ= 90 °C at 515 m; flow rate 200 m3/h

AKP‐4: Τ= 48 °C at 180 m; flow rate 40 m3/h

High Concentration of CO2

83oC + CO2 150 m3/h

ChiosChios‐‐SamothraceSamothrace‐‐LesvosLesvos

NenitaNenita areaarea: 5 of the : 5 of the explexpl. . wells reached at temp. up wells reached at temp. up to 88to 88°°CC

3 shallow exploration 3 shallow exploration drillholesdrillholes: : ((<<120120m): m): 8080--100100°°CC, 150m, 150m33/h/h

Geoth.fieldGeoth.fieldTemperatureTemperature

((°°C)C)

PolichnitosPolichnitos6767‐‐9292

ArgennosArgennos8686

StypsiStypsi‐‐NapiNapi4242‐‐110110

0 50 100 150 200 250 300 350

Bunary cycle plantsConvectional power plants

Paper & wood processingSalt extraction

Wood dryingWool cleaning

Oil recoveryBiological mud digestion

Water desalination

AquacultureFood processing

Cleaning animal sheltersFruit & vegetable drying

Soil warmingGreenhouse heating

DeicingGeothermal heat pumps

Absorption coolingHot water

Floor panelsHeating panels

PoolsBalneotherapy

Temperature (oC)

Industrial uses

Space heating/cooling

Agri-business uses

Balneotherapy, pools

The (modified) Lindal diagram, showing the possible use of geothermal fluids at different temperatures

Power Generation from Medium Enthalpy Geothermal FluidsPower Generation from Medium Enthalpy Geothermal Fluids

Binary (or Organic Binary (or Organic RankineRankine) Cycle (ORC) power plants) Cycle (ORC) power plantsusing fluids of 85using fluids of 85--175175°°C C (USA, Philippines, Hawaii islands, (USA, Philippines, Hawaii islands,

PortugalPortugal--Azores, Germany etc.)Azores, Germany etc.)

Binary Power Plant in HawaiiBinary Power Plant in Hawaii

19901990: : The P.G.V.The P.G.V. acquired the permit for a acquired the permit for a 60 60 MW power plant in MW power plant in PunaPuna

19931993: : operation of aoperation of a 30 30 MW plantMW plant

It covers theIt covers the 20% 20% of the island needsof the island needs

8 8 MW expansionMW expansion

The opposition of the inhabitants was very The opposition of the inhabitants was very strong in the beginning strong in the beginning ((mostly for religious and mostly for religious and environmental reasons) environmental reasons) 

Today it is the most reliable power source Today it is the most reliable power source 

Total reinjection of the fluidsTotal reinjection of the fluids

Mammoth Pacific binarypower plants at the CasaDiablo (USA) geothermal field

Binary power plant in Mexico

NevadaNevada--Blue MountainBlue Mountain

California California -- East MesaEast Mesa

Utah geothermal project with  a series of small 

(250kWe) binary modular units

Combined electric and direct geothermal cascade usesCombined electric and direct geothermal cascade uses

150oC

120oC

AltheimAltheim (Austria) CHP System(Austria) CHP System

NeustadtNeustadt‐‐GleweGlewe (Germany) CHP System(Germany) CHP System

1995: District Heating (11MW1995: District Heating (11MWth th ))

2003: CHP (ORC 210kW2003: CHP (ORC 210kWee))

Temperature: 98Temperature: 98°°CC

Geothermal power plant in Geothermal power plant in SvarstengiSvarstengi (Iceland) & Blue Lagoon Spa resorts(Iceland) & Blue Lagoon Spa resorts

Geothermal power plant in Wairakei (New Zealand).The geothermal fluids cascade to a shrimp farm pond

Industrial Applications of medium enthalpy geothermal energyIndustrial Applications of medium enthalpy geothermal energy

Vegetable dehydration plant in Nevada: one well with 132Vegetable dehydration plant in Nevada: one well with 132°°C, C, 113ton/day of dehydrated onions (May113ton/day of dehydrated onions (May‐‐October), celery in MarchOctober), celery in March‐‐

April and carrots from November to January.            April and carrots from November to January.            75 employees all year round. 75 employees all year round. 

Tomato dehydration with geothermal energy in Neo Tomato dehydration with geothermal energy in Neo ErasmioErasmio ((XanthiXanthi))

Geothermal Fluid entry

Geothermal Fluid Exit

MilosMilos island (Greece). Proposed medium enthalpy (85island (Greece). Proposed medium enthalpy (85‐‐98oC) geothermal energy 98oC) geothermal energy utilisationutilisation for power generation, desalination and other usesfor power generation, desalination and other uses

Reykjavik 1932: Use of conventional fuels for heating

Reykjavik today: Utilisation of geothermal energy for district heating

89% of the heating requirements in Iceland are covered by geothermal energy

Heat exchangersHeat exchangers

Distribution pumpsDistribution pumps

Production well 

& 

Distribution networks

The first geothermal district heating system in USAThe first geothermal district heating system in USA

Geothermal Geothermal greenhouses next to greenhouses next to geothermal power geothermal power plant in plant in GufudalurGufudalur, , HveragerðiHveragerði ((IcelandIceland))

Geothermal Geothermal greenhouses in greenhouses in Idaho (USA)Idaho (USA)

Aquaculture installation at Vistonida Lake with low temperature (36oC) –Possible final step in cascade utilisation of Geothermal Cogeneration

Heating of modern greenhouses with cogeneration (Greece)

Accelerated Growth of Asparagus with Geothermal Accelerated Growth of Asparagus with Geothermal Soil Heating (210.000m2 in Greece)Soil Heating (210.000m2 in Greece)

COGENERATION OF HEAT AND POWER (CHP) FROM MEDIUM ENTHALPY COGENERATION OF HEAT AND POWER (CHP) FROM MEDIUM ENTHALPY GEOTHERMAL FLUIDSGEOTHERMAL FLUIDS

EXPECTED TEMPERATUREEXPECTED TEMPERATURE:: 150150οοCC atat 16001600‐‐1700 1700 mm

EXPECTED FLOWRATEEXPECTED FLOWRATE:: 50 50 kg/s (180m3/h)kg/s (180m3/h)

GEOTHERMAL CAPACITYGEOTHERMAL CAPACITY:: 25 25 MWtMWt

CONVERT TO ELECTRICITYCONVERT TO ELECTRICITY:: 4 4 MWMWee (binary cycle technology)(binary cycle technology)

RESIDUAL THERMAL CAPACITYRESIDUAL THERMAL CAPACITY:: 21 21 MWtMWt

POWER PLANT COSTPOWER PLANT COST

2 GEOTHERMAL WELLS + INSTALLATIONS2 GEOTHERMAL WELLS + INSTALLATIONS€€ 6.000.000  6.000.000  

€€ 5.000.0005.000.000

ANNUAL POWER PRODUCTIONANNUAL POWER PRODUCTION:: 28.000 28.000 MWhMWh/year/year ((use factoruse factor 80%)80%)

INCOME FROM ELECTRICITY SALEINCOME FROM ELECTRICITY SALE:: €€ 2.2.24240.000  (0.000  (€€ 8080//MWhMWh))

GREENHOUSE HEATINGGREENHOUSE HEATING:: ca 260.000mca 260.000m2

THERMAL ENERGY: 73.000 THERMAL ENERGY: 73.000 MWhtMWht/year /year APPROX. INCOME (APPROX. INCOME (vsvs CHP Nat. Gas): CHP Nat. Gas): 

€€ 2.900.000/year2.900.000/year

ASPARAGUS SOIL HEATING: ca 600.000mASPARAGUS SOIL HEATING: ca 600.000m2

THERMAL ENERGY: 12.500 THERMAL ENERGY: 12.500 MWhtMWht/year /year APPROX. INCOME: APPROX. INCOME: €€ 500.000/year500.000/year

TOTAL YEARLY INCOMETOTAL YEARLY INCOME

INVESTMENT AMORTISATION INVESTMENT AMORTISATION €€ 5.640.000/year5.640.000/year

< 2 YEARS< 2 YEARS

According to world‐wide experience and examples, the ORC power generation projects can easily achieve economic viability when a heating segment is added to the utilisation grid. 

Heat and power cogeneration can result in significant cost savings and in the reduction of the payback period.

The important medium enthalpy geothermal potential in “sensitive” areas of Greece, in combination with available and mature technology solutions, can contribute significantly to the development of local communities and improve national energy equilibrium

Minimum to zero environmental impacts

CONCLUSIONSCONCLUSIONS

THANK YOUTHANK YOU

FOR YOUR ATTENTIONFOR YOUR ATTENTION