This document proposes a new method for more fairly allocating the environmental impacts and greenhouse gas emissions of electric power systems to different regions based on both electricity consumption and transmission loads. The method uses network analysis of power grids to calculate the "energy distance" representing transmission loads. It then applies this energy distance analysis along with standard life cycle assessment to re-allocate a country's total greenhouse gas emissions from electricity generation to different regions. The approach provides a more comprehensive picture that considers both consumption and transmission infrastructure impacts compared to conventional allocation based solely on consumption. The method is demonstrated through its application to Chile's national power grid and results in different regional allocation outcomes.

1. Towards Fair Allocation of Environmental
Responsibility to Electric Network Users
Heetae Kim, Petter Holme
Department of Energy Science, SKKU, South Korea

2. Motivation
10km
Santiago
Curico
50km
Cost-benefit mismatch

3. Electric power system and Greenhouse gas
Transmission
From resources to energy services and greenhouse gas (GHG) emission
Consumption Generation
Power plantsUsers Infrastructures

4. Electric power system
Consumption Generation
CO2
Infrastructures Power plantsUsers
Greenhouse gas emission of generation:
- estimated from consumption

5. Electric power system
Power plantsUsers
TransmissionConsumption
Infrastructures
Transmission
distance
? km
Greenhouse gas emission of transmission:
- should not be estimated from consumption

6. How to estimate GHG: ideal
Total emissions
Resource
combustion
Conversion factor
Resource
consumption
Electricity
consumption
Transmission facilities Conversion factor Facility use
km
Transmission
distance
CO2
CO2
×
×
Functional index
Environmental
impacts
Conversion
factor ×=
measured by
measured by
conversion process corresponding to transmission and generation
Transmission
facilities
Resource
combustion
=
=

7. How to estimate GHG: real
Total emissions
Resource
combustion
Conversion factor
Resource
consumption
Electricity
consumption
Transmission facilities Conversion factor Facility use
km
Transmission
distance
CO2
CO2
×
×
Functional index
Environmental
impacts
Conversion
factor ×=
Transmission load is difficult to consider separately
Transmission
facilities
Resource
combustion
=
=
measured by
measured by

8. How to estimate GHG: current
Total emissions
Resource
combustion
Conversion factor
Resource
consumption
Electricity
consumption
Transmission
facilities
Conversion factor Facility use
km
Transmission
distance
CO2
CO2
×
×
Functional index
Environmental
impacts
Conversion
factor ×=
Transmission
facilities
Resource
combustion
Transmission
facilities
Resource
combustion
=
=
measured by
measured by
The merged conversion factor and functional index are used
However, the transmission load will not be negligible because …
Environmental impacts from transmission facility is neglected (< 5 % of total)
CO2
×=
Electricity
consumption
Merged
conversion
factor

9. Environmental impacts timeline
Construction Operation & maintenance
Transmission
facilities
Resource
combustion

10. •Increasing cost of transmission facilities
- Super conductive material, smart grid
Environmental impacts timeline
Construction Operation & maintenance
Transmission
facilities
Resource
combustion

11. •Increasing cost of transmission facilities
- Super conductive material, smart grid
•Decreasing fossil fuels
- Solar power, wind power, etc.
•Sensitive stakeholder economy
- International electric power trade and transmission
Environmental impacts timeline
Construction Operation & maintenance
Transmission
facilities
Resource
combustion

12. International transmission projects
NorNedAsia Super GridDeserTec

13. Research purpose
✴ Allocate environmental impacts of electric power to regions
according to both electricity consumption and transmission load
✴ Integrate network theory into Life cycle assessment(LCA)
allocate

14. Method outline
Energy distance2 GHG allocation3Total GHG emissions1

15. Inventory analysis
SIC center of Economic Load Dispatch (CDEC-SIC)
✓the main national electricity company
✓serves 92% of country’s population
✓10 regions out of 15
✓42 provinces out of 57
Data collection
✓2007 to 2012
System boundary
"ISO 14044:2006, Environmental management - Life cycle assessment
- Requirements and guidelines." ISO (2006)

16. Developing Chilean conversion factor
g CO2/ kWh GWh
0.006 325
0.266 13,450
0.157 7,946
0.285 14,385
0.027 1,358
0.020 1,013
0.239 12,072
= 23.02 Mt CO2-eq
Greenhouse gas (GHG) emissions
of Chilean electric power system
CDEC-SIC Annual report (2014)
R. Itten, R. Frischknecht, M. Stucki, "Life Cycle Inventories of Electricity Mixes and Grid" ESU-services Ltd. (2013)

17. Network generation
<Transmission system dada>
Node
(Poser plant)
Link
(Transmission line)
Agua
santa
Placilla
Node
(Substation)
CDEC-SIC Annual report (2014)
466 nodes
↳129 power plants
291 substations
46 towers
543 edges

18. Network generation
466 nodes
↳129 power plants
291 substations
46 towers
543 edges

19. Transmission algorithm
Amount of electricity consumption × Transmission distance
i : a substation node
j : a power plant node
aij: electricity supply from j to i
dij : transmission distance from j to i
nhd(i) : neighbor nodes of i
Edi : energy distance of i
i
j Power plant
Substation
Transmission
distance dij
2
A
B
1
Greedy algorithm
↳the nearest substation has the top priority
and the others are supplied subsequently
Possible
pair
Transmission
distance
Optim
al
Electricity
supply aij
Edi =
f (aij ,dij )
j∈nhd(i)
k
∑
f (aij ,dij )
j∈nhd(i)
k
∑
i=1
n
∑
Energy distance
Lo, K. L. et. al, Generation, Transmission & Distribution, IET. 1(6) 904-911, 2007

20. Result
Transmission
distance
Electricity
consumption
1200 MWh 4000 km 10 %
Comprehensive
system load
0 0 0

21. Result

22. Result
by energy distanceby consumption
676
66000
kt CO2
Regional greenhouse gas emissions allocated
30000

23. Conclusion
Network analysis on electric power grid
↳ Useful complement to LCA analysis
Transmission load adjusted allocation
↳ Consider both of electricity consumption and transmission distance
Re-allocate environmental impacts to users
↳ Life cycle assessment on GHG emissions
↳ Energy distance analysis
↳ Make the fair allocation possible

24. Acknowledgement
Thank you for your attention!
Any question?
Prof. Petter Holme Fariba Karimi Heetae Kim Eun Lee Minjin Lee Prof. Sang Hoon Lee
National Research
Foundation in Korea
kimheetae@gmail.com