Einar Gunnlaugsson, Reykjavik Energy. Iceland Geothermal Conference 2013 March 5-8, 2013, Harpa, Reykjavík

1. The Hengill geothermal
area – overview
Einar Gunnlaugsson

2. 2
• The Hengill geothermal
system is located about 30 km
east of Reykjavík
• It is in the middle of the
western volcanic zone
Hengill
Hengill volcanic system
South Iceland Seismic Zone
Hengill

3. 3
The Hengill area
is about 110-115
km2
Estimated to
sustain about
700 MWe power
productions in
several power
plants
Nesjavellir
Hellisheiði
Nesjavellir
Hellisheiði
Power plants:
Bitra
Bitra
Hverahlíð
Future plants:
Hverahlíð

4. 4
Nesjavellir
Hellisheiði
Master plan for
utilization of
the energy
resources
• Appropriate for
• development
• protection
• consideration
Bitra
Bitra
Grændalur
Grændalur
Hverahlíð
Gráuhnúkar
Meitill
Hverahlíð
Gráuhnúkar
Meitill
Þverárdalur
Innstidalur
Ölfusdalur
Ölfusdalur
Þverárdalur
Innstidalur

5. 5
• Started around 1950 with the
purpose of exploitation
• Geological mapping
• Bed rock
• Hydrology and alteration
• Geochemical study
• Geophysical study
• Resistivity (TEM – MT)
• Seismicity used to locate
fractures
Surface exploration
• Pilot plant used steam from
drillhole at Hveragerði to
generate electricity in 1944

6. 6
Geological
map -
Bedrock

7. 7
Volcanic systems

8. 8
Temperature based on CO2

9. 9
Geophysics -
resistivity
• Gives information about
distribution of geothermal
activity

10. • First phase of drilling 1965 –1972
• Pilot plant
• Second phase of drilling started 1982
• 11 drillhole drilled until 1986
• Decision to build a power plant 1986
• Start of operation 1990
• First phases built before the act of
EIA
• Modular development
Nesjavellir

12. 12
• EIA at Hellisheiði for 120 MWe +
400 MWth
• EIA extension of the field
additional 120 MWe
• Additional 5 MWe production from
each unit allowed without EIA
• Low pressure unit allowed without
EIA
Hellisheiði
Environmental Impact Assessment
• Installed capacity 303 MWe and
133 MWth

13. 13
• After drilling of 3 to 5 research
drillholes only limited information has
been collected about the geothermal
reservoir
• Geothermal projects different from
most other projects all information are
not available at this stage
• Therefore the permit process has to be
more flexible than it is today
Environmental
Impact Assessment

14. • Electricity 90 MW 2006
• Low pressure unit 2007
• Electricity 90 MW 2008
• Hot water to Reykjavík 2010
• Electricity 90 MW fall 2011
Hellisheiði
M

15. 15
57 production wells
Gráuhnúkar
Hverahlíð
17 re-injection wells
Bitra
Hellisheiði

16. Hellisheiði - Re-injection
• Two location
• Distance 3.5 km and 1
km from the power plant
• Number of re-injection
wells: 17
• Directional well 15,
vertical wells 2
• Average length 1968 m
(994-3012 m)
• Average depth 1753 m
(899-2760 m)

18. Hverahlíð
Hellisheiði Power Plant

19. Hverahlíð - original plan 2007 - EIA

20. 24.3.2013 Ráðstefna um orku…
Hverahlíð
Norðurhálsar
Skálafell

21. 21
Hverahlíð new information

22. Conclusion
• Geothermal development differ from
most other projects
• All information are not available when
EIA is required
• Therefore the permit process has to be
more flexible than it is today especially
after master plan for utilization of the
energy resources has been adopted
and geothermal fields grouped
according to
• development
• protection
• consideration

23. Thank you