The document discusses the role of geothermal energy in smart energy systems, highlighting the importance of energy quality management and the challenges faced by electricity producers and consumers. It emphasizes the potential for significant energy savings through improved geothermal heat utilization and district heating networks. Future concepts include innovative district heating systems that integrate with local renewable energy sources.

1. Orkustofnun
The National Energy Authority
Prof. Dr. Gudni A Jóhannesson
Director General
GEORG 25. Nov 2016
Role and Opportunities of
Geothermal in Smart
Energy Systems

2. 1
Originally by Cullen & Allwood 2010
Global Primary Energy Use 2006

3. Definition of Exergy and Energy
Quality
Heat reservoir
Mechanical work
- ExergyHeat flow
Anergy
Environment
Quality of energy at T1
(Max exergy output)/energy
Exergy destroying processes
Electricity or fuels converted
directly to heat
Mixing of water at different
temperatures
Friction losses in fluid flow

4. Quality of energy
• Quality of energy is the proportion of the
stored energy that can be used to
generate work.
T0
Tr Qr
Work

5. Exergy X for a heat source depending on
temperature
T0
Tr Qr m cHitastig varmageymis Hlutfall
o
C K hágildisorku
500 773,15 0,43
400 673,15 0,38
300 573,15 0,33
250 523,15 0,29
200 473,15 0,25
150 423,15 0,20
100 373,15 0,15
80 353,15 0,12
60 333,15 0,10
40 313,15 0,07
20 293,15 0,03
0 273,15
Viðmiðunarhitastig 273,15
W
Temperature
Proportion
exergy
Ref temperature
Electricity and fossil fuels
Quality factor 0,9 – 1,0

6. How Smart is Smart
• What is our perspective
– The electricity producer – maximum revenues
– The consumer – adequate service for a
minimum cost
– Global climate change – minimum emissions
• Smart Stupid grids
• Smart energy systems
• Good energy quality management EQM

7. Energy Quality Management
Community Level

8. Global EQM Potential
Total Primary
energy use
475 TWh
Heating 233 TWH
Saving potential by
Energy Quality
Management
150 TWh?
Total coal burning
127 TWh
2006 values

9. TheLindalDiagram
http://www.therockymountaingoat.com/2014/02/valemount-may-get-geothermal-workshop/

10. Geothermal Heat 2014
28.1 PJ in total

11. The Deep Drilling Project
>500 OC
250 OC

12. Heat pump – highest theoretical COP
0.00
5.00
10.00
15.00
20.00
25.00
30.00
35.00
40.00
45.00
50.00
-5 0 5 10 15 20 25 30
Nothitastig 35 C
Nothitastig 55 C
0TT
T
r
r

Source temperature OC

13. Heat pumps – measured COP
Fig. 1: Values of COP for brine/water heat pumps (as used typically in
geothermal heat pump systems), measured in the Heat Pump Test Centre
Toess (extract from http://www.wpz.ch/)

14. The Price for Exergy
• Reykjavik Energy – marginal cost
– Electricity including distribution
• Energy price 13,79 kr/kWh
• Exergy price 13,79 kr/kWh
– Hot water
• Price 131,45 kr/m3 DT=(80-40) K
• 46,4 kWst Reservoir quality at 80 C = 0,12
• Exergy price = 2,83 kr/kWh/0,12 = 23,6 kr/kWh
• Heat pump alternative – equalized marginal cost
• Relative COP = 0,58 x COPtheoretical

15. The Role of District Heating and
Cooling
H. Lund et al. / Energy 68 (2014) 1e11

16. Supplied energy for district heating in Sweden, TWh
Oil
Biofuels, waste,
peat
Heatpumps
Waste
heat
Natural gas
Coa
l
Electricity

17. Increased market penetration
• Integration into the total energy system
• Increased penetration of district heating
and cooling networks
• New generation of networks - prosumers
• Industries
• Biocultures
• Absorptive and adsorptive cooling
• Improved public acceptance
• Deposition of gasses with reinjection

18. Future concepts?
• The HC-radiator
80OC
40OC
Heating
Cooling
No mechanical heating or cooling
Ambient outside air

19. Future Concept - Villa NOPOLI?
• Village with no powerlines
• District heating system with mixture of
water and ethanol
• Ethanol is evaporated and condensed on
house level for small electricity generation,
cooking and afternoon toddy.
• Combined with local generation with wind
or solar. (TESLA Powerwall?)