GHG Emission Tracking Report Abhishek Hundiwale Lead Engineering Specialist November 14, 2016
CAISO Public
Agenda
• Background • GHG emission calculation – Total GHG emissions to serve ISO load – Cumulative effect of EIM on GHG emissions • Conclusion and next steps
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Background
• ISO has committed to track GHG emissions serving ISO load • Report is preliminary and for informational purposes only • Does not replace CARB’s regulation for GHG accounting
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Total GHG emissions to serve ISO load Total GHG Emission to serve ISO load 7,500,000 7,000,000 6,500,000
mTCO2
6,000,000 5,500,000 5,000,000 4,500,000 4,000,000 3,500,000 3,000,000 Jan
Feb
Mar
Apr
May 2014
Jun 2015
Jul
Aug
Sep
Oct
Dec
2016
YTD (January - September) million mTCO2
2014
2015
2016
GHG Emission to serve ISO load
51.81
49.53
43.15
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Methodology to track GHG emissions to serve ISO load • •
• • •
Comparison GHG emissions pattern for years 2014 - 2016 Total GHG emissions to serve ISO load = GHG emissions from internal ISO dispatches including dynamic schedules + GHG emissions from imports serving ISO load (imports minus exports) + GHG Impact from EIM transfers into ISO using counter-factual determination - GHG Impact from EIM transfers out of ISO using counter-factual determination GHG Emissions (mTCO2) = resource heat rate (MMBTU/MWh) * CO2 emission factor by resource type (mTCO2/MMBTU) * Energy (MWh) For unspecified imports emission rate of 0.428 mTCO2/MWh used Higher solar production along with improved hydro conditions in 2016 contribute to GHG emissions reductions compared to 2014 – 2015. CAISO Public
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Example 1: Total GHG emissions to serve ISO load ISO
Tiso,in = 10 MW
GA = 10 MW (Gas) GB = 50 MW (Gas) GC = 100 MW (Wind) Load = 200 MW Imports = 50 MW Exports = 20 MW
External EIM Area GX = 3 MW (Hydro) GY = 1 MW (Coal) GX = 6 MW (Gas)
Gas Resource Heat Rate (BTU/KWh) 10,000 9500 8500
GHG Emission GHG Emission Rate Rate (mTCO2/MMBTU) (mTCO2/MWh) 0.053165 0.053165 0.053165
0.53165 0.50507 0.45190
EIM Case Total GHG emission to serve ISO load GHGiso = GHGGiso + GHGIiso – GHGEiso + GHGTiso,in = 29.77 + 21.4 – 8.56 + 3.82 = 46.43 mTCO2 Where: GHGGiso = GHGG,A + GHGG,B + GHGG,C = (8500/1000) MMBTU/MWh x 0.053165 mTCO2/MMBTU x10 MWh + (9500/1000) MMBTU/MWh x 0.053165 mTCO2/MMBTU x 50 MWh + 0 = 29.77 mTCO2 GHGIiso = 50MWh x 0.428 mTCO2/MWh = 21.4 mTCO2 GHGEiso = 20MWh x 0.428 mTCO2/MWh = 8.56 mTCO2 GHGTiso,in = 3.82 mTCO2 (Based on EIM counter-factual comparison) CAISO Public
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GHG emission calculation – Cumulative effect of Energy Imbalance Market on GHG emissions • Uses counter-factual determination without EIM transfers • Compares – EIM Transfers into ISO: GHG of external resources supporting ISO imbalances and internal ISO supply displaced by EIM transfers to the ISO – EIM Transfers out of ISO: GHG of internal supply supporting transfers and external resources displaced by EIM transfers out of ISO • Positive benefits indicate how EIM transfers have reduced GHG emissions relative to a counter-factual assessment of emissions across the ISO and EIM balancing authority areas without EIM transfers CAISO Public
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CAISO Public 30-Sep
23-Sep
16-Sep
9-Sep
2-Sep
26-Aug
19-Aug
350,000
12-Aug
5-Aug
29-Jul
22-Jul
15-Jul
8-Jul
1-Jul
24-Jun
17-Jun
10-Jun
3-Jun
27-May
20-May
13-May
6-May
29-Apr
22-Apr
15-Apr
8-Apr
1-Apr
25-Mar
18-Mar
11-Mar
4-Mar
26-Feb
19-Feb
12-Feb
5-Feb
29-Jan
22-Jan
15-Jan
8-Jan
1-Jan
Reduced GHG (mTCO2)
Cumulative effect of Energy Imbalance Market on GHG emissions EIM GHG Reduction 136,724 mTCO2
300,000
250,000
200,000
150,000
100,000
50,000
0
-50,000
YTD Cumulative EIM GHG Reduction
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Example 2: EIM effect on GHG emissions ISO
Tiso,in = 10 MW
GA = 10 MW (Gas) GB = 50 MW (Gas) GC = 100 MW (Wind) Load = 200 MW Imports = 50 MW Exports = 20 MW
External EIM Area GX = 3 MW (Hydro) GY = 1 MW (Coal) GX = 6 MW (Gas)
GA = 14 MW ↑ 4 MW GB = 16 MW ↑ 6 MW GC = 100 MW Load = 200 MW Imports = 50 MW Exports = 20 MW
EIM Case •
•
Tiso,in=0MW↓10 MW
ISO
External EIM Area GX = 0 MW ↓3 MW GY = 0 MW ↓1 MW GZ = 0 MW ↓6 MW
Counter-Factual (CF) Case
GHG emissions of external resources supporting EIM transfer are determined by comparing dispatch of the EIM case with counter-factual (CF) case without transfers: – Tiso,in = 10 MW transfer provided by • ∆Gx = 3 MW (Hydro) • ∆Gy = 1 MW (Coal resource with heat rate = 10000 BTU/KWh) • ∆Gz = 6 MW (Gas resource with heat rate = 9000 BTU/KWh) GHG emissions of internal ISO resources displaced by EIM transfers are determined by comparing EIM case with the counter-factual case without transfers: – Tiso,disp • ∆GA= 4 MW (Gas with heat rate of 10000 BTU/KWh) • ∆GB= 6 MW (Gas with heat rate of 9000 BTU/KWh) CAISO Public
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Example 2: EIM effect on GHG emissions Overall EIM GHG Reduction = (-1)*(GHGTiso,in - GHGTiso,disp) = (-1)*(3.82 - 4.99) mTCO2 = 1.17 mTCO2 Where: GHGTiso,in = ∆Gx x 0 mTCO2 + ∆GY x 0.09471 mTCO2/MMBTU x (10000/1000) MMBTU/MWh + ∆GZ x 0.05316 mTCO2/MMBTU x (9000/1000) MMBTU/MWh = 3.82 mTCO2 GHGTiso,disp = ∆GA x 0.05316 mTCO2/MMBTU x (10000/1000) MMBTU/MWh + ∆GB x 0.05316 mTCO2/MMBTU x (9000/1000) MMBTU/MWh = 4.99 mTCO2
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Conclusion • Tracking report will be published monthly • Report will – Track annual GHG total emissions serving ISO load – Show year-over-year and seasonal trends – Illustrate effects of EIM on GHG emissions
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Questions
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