A battery had the following activity derived from hourly meter data.
Consumed charging energy (MWh)
5,000
Injected discharging energy (MWh)
4,250
Round-trip efficiency
85%
Assess Charging Emissions
Based on location and following the PECA methodology, REsurety was chosen as the emissions data source.
Marginal Emissions Rate (MER)
Average charging MER (tCO2/MWh)
0.20
Total charging carbon impact (tCO2)
1,000
Hour
MWh
Average MER (tCO2/MWh)
Total Carbon Impact (tCO2)
1
0
0
2
0
0
3
0
0
4
0
0
5
0
0
6
200
0.15
30
7
1000
0.25
250
8
2000
0.2
400
9
1100
0.1
110
10
700
0.3
210
11
0
0
12
0
0
13
0
0
14
0
0
15
0
0
16
0
0
17
0
0
18
0
0
19
0
0
20
0
0
21
0
0
22
0
0
23
0
0
24
0
0
Match Hours of Charging with CFE Generation
PECs are retired to match hours of charging, complying with the EnergyTag Standard.
This example uses average MER to calculate carbon impact. In practice, carbon impact is calculated hourly.
Retired PECs
5000
Retired PEC Average MER (tCO2/MWh)
0.18
Percent hourly-matched
100%
Carbon Impact of Retired PECs (tCO2)
-900
Remaining charging carbon impact (tCO2)
1,000 – 900 = 100
Percent emissions-matched
90%
Submit Project Data for Verification and PEC Issuance
The PEC registry verifies the meter data, emissions data, and retired PECs. Upon completion, a Power Emissions Proof Report will be created along with the issued PECs.
Average discharging MER (tCO2/MWh)
0.45
Gross discharge carbon impact (tCO2)
4,250 * 0.45 = -1,912.5
Adjusted discharge carbon impact (tCO2)
-1,912.5 + 100 = -1,812.5
Issued PECs
4,250
Issued PEC Average MER (tCO2/MWh)
0.43
Hour
MWh
Average MER (tCO2/MWh)
Total Carbon Impact (tCO2)
1
0
0
2
0
0
3
0
0
4
0
0
5
0
0
6
0
0
7
0
0
8
0
0
9
0
0
10
0
0
11
0
0
12
0
0
13
0
0
14
0
0
15
-1000
0.4
-400
16
-200
0.45
-90
17
-1700
0.5
-850
18
-800
0.3
-240
19
-550
0.6
-330
20
0
0
21
0
0
22
0
0
23
0
0
24
0
0
Carbon Accounting
By shifting the hours of CFE generation, this battery has converted 5,000 low-impact PECs into 4,250 high-impact PECs.
Net carbon impact (tCO2)
(charging + discharging)
1000 + -1,912.5 = -912.5
Adjusted Net Carbon Impact (tCO2)
(charging + discharging + retired PECs)
(1000 + -900) + -1,912.5 = -1,812.5
Hour
MWh
Average MER (tCO2/MWh)
Total Carbon Impact (tCO2)
1
0
0
2
0
0
3
0
0
4
0
0
5
0
0
6
200
0.15
30
7
1000
0.25
250
8
2000
0.2
400
9
1100
0.1
110
10
700
0.3
210
11
0
0
12
0
0
13
0
0
14
0
0
15
-1000
0.4
-400
16
-200
0.45
-90
17
-1700
0.5
-850
18
-800
0.3
-240
19
-550
0.6
-330
20
0
0
21
0
0
22
0
0
23
0
0
24
0
0
Contract Settlement
Settling the PEC agreement using a predetermined carbon price.
