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CO2 SAVING BY USING GEOTHERMAL ENERGY FOR HOUSE HEATING IN

Mai 2008

Einar Gunnlaugsson Outline • Brief introduction to geothermal activity in Iceland • The use of geothermal energy in Iceland • District heating in Reykjavík • Production of geothermal water and changes in water level

• CO2 saving by using geothermal water in Reykjavík

• CO2 saving in countries using carbonate rich low-temperature geothermal water, example from Slovakia ICELAND Size: 104.000 km2 Population: 311,396

Average Jan. temp: -0.4°C Mean annual temp: 5°C Average July temp.: 11.2°

July 2007

Geothermal activity in Reykjavík

During Reykjavik's first 1000 years geothermal heat was primarily used for washing, bathing and cooking.

For centuries women carried the laundry to the hot springs now in mid Reykjavík. Reykir

The first house heated with geothermal water in 1909 Geothermal steam used for heating in 1912

Sturlureykir Twenty largest geothermal district heating utilities

Reykjavík Suðurnes Reykjavík- the world’s largest municipal geothermal heating service Hveragerði Skagafjörður Akranes Borgarfjörður Mosfellsbær Laugarás Húsavík Ólafsfjörður Dalvík-Árskógsströnd Flúðir Þorlákshöfn Egilsstaðir og Fell Rangæinga Blönduós Siglufjörður Húnaþing vestra 3 0 10.000 20.000 30.000 40.000 50.000 60.000 70.000 m 1928

Drilling started in in Reykjavík for hot water.

14 drillholes drilled

Result about 14 l/s of 87°C water. 1930 District Heating in Reykjavík

- 3 km long pipeline

-Two school houses, hospital, swimming pool and 70 private houses connected. Reykir and Reykjahlíð

Prior to exploitation artesian flow: 120 l/s Area: 5.5 km2

Temp: 65-100 °C Capacity : 1700 l/s No of exploitation wells : 34 Reykjahlíð field Reykir field Laugarnes

– Area: 0.28 km2 – Temp: 125-130 °C – Capacity : 330 l/s – No of exploit. wells : 10 Laugarnes field Elliðaár

Area : 0.08 km2 – Temp: 85-95 °C – Capacity : 220 l/s – No of exploitation wells : 8 Elliðaár field 1933 About 3 % of Reykjavik's population connected to the District Heating Benefits of District Heating

Clean air - No smoke from chimneys 300000

200000 r

Reduction of CO2

100000 emission in Reykjavik

0

1960 1965 1970 1975 1980 1985 1990 1995 CO2 saving using geothermal water in Reykjavík

• Compared to other energy sources

• Coal: Saving of CO2 form 87,000,000 to 132,000,000 tonnes • Average 109,000,000 tonnes CO2 saving using geothermal water in Reykjavík

• Compared to other energy sources

• Gas: Saving of CO2 form 46,000,000 to 131,000,000 tonnes • Average 89,000,000 tonnes CO2 saving using geothermal water in Reykjavík

• Compared to other energy sources

• Oil: Saving of CO2 form 71,000,000 to 92,000,000 tonnes • Average 82,000,000 tonnes CO2 saving using geothermal water in Reykjavík

• Compared to other energy sources

• Total saving of CO2 form 90,000,000 to 110,000,000 tonnes Space heating

100% 1% Oil Electricity 90% 10 % 80%

70%

60% 50% Geothermal 89 % 40%

30% The primary direct use of geothermal 20% energy in Iceland is for space heating 10%

0% 1970 1975 1980 1985 1990 1995 2000 Chemistry of geothermal water

• Low-temperature geothermal water is usually low in carbonate and are

not emitting CO2 to the atmosphere • The chemical composition of low-temperature water in Iceland has in

most cases similar CO2 content as groundwater

• In some cases the geothermal water is rich in carbonate but still the

CO2 emission is negligible Example from Slovakia

• In Galanta in Slovakia geothermal water was used to replace natural gas • 9,000 GJ/year heat production was modified • Natural gas replaced by carbonate rich geothermal water

• Although the water is rich in carbonate its CO2 emission is negligible – about 0.3 g CO2/kWh

• Reduction of about 5,000 tonnes of CO2 emission annually Galantaterm - Slovakia

Production of heat from geothermal water and gas in the period 1999 - 2007

Emissions CO2 from gas and from geothermal water

1 200,00 Geothermal 1 000,00 Total( Energycentre) CO2 emission from gas 800,00 and geothermal water 600,00

CO2 (t/y) 400,00

200,00

0,00 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 Year Galantaterm - Slovakia

Savings of CO2 emission by using geothermal water instead og natural gas

Emission if natural gas entirely used for heating

Emission Conclusion

• One of the cleanest energy source

– Reduces CO2 emission – About 100,000,000 tonnes of CO2 has been saved in Reykjavík by using geothermal water for heating houses • Sustainable energy source • In all cases domestic energy and used locally – Reduces import of other energy sources such as fossil fuels Thank you