Washington Administrative Code
Title 463 - Energy Facility Site Evaluation Council
Chapter 463-80 - Carbon dioxide mitigation program for thermal electric generating facilities
Section 463-80-050 - Calculating total carbon dioxide emissions to be mitigated
Current through Register Vol. 24-18, September 15, 2024
(1) Step 1 is to calculate the total quantity of CO2. The total quantity of CO2 is referred to as the maximum potential emissions of CO2. The maximum potential emissions of CO2 is defined as the annual CO2 emission rate. The annual CO2 emission rate is derived by the following formula unless a differing analysis is necessary or appropriate for the electric generating process and type of equipment:
CO2rate |
= |
Fs x Ks |
x Ts + |
F1 x K1 |
x T1 + |
F2 x K2 |
x T2 |
F3 x K3 |
x T3. . . |
Fn x Kn |
x Tn |
2204.6 |
2204.6 |
2204.6 |
2204.6 |
2204.6 |
where:
CO2rate |
= |
Maximum potential emissions in metric tons per year |
F1 - n |
= |
Maximum design fuel firing rate in MMBtu/hour calculated as manufacturer or designer's guaranteed total net station generating capability in MWe times the new equipment heat rate in Btu/MWe. Determined based on higher heating values of fuel |
K1 - n |
= |
Conversion factor for the fuel(s) being evaluated in lb CO2/MMBtu for fuel Fn |
T1 - n |
= |
Hours per year fuel Fn is allowed to be used. The default is 8760 hours unless there is a limitation on hours in a site certification agreement |
Fs |
= |
Maximum design supplemental fuel firing rate in MMBtu/hour, at higher heating value of the fuel |
Ks |
= |
Conversion factor for the supplemental fuel being evaluated in lb CO2/MMBtu for fuel Fn given fuel |
Ts |
= |
Hours per year supplemental fuel Fn is allowed. The default is 8760 hours unless there is a limitation on hours in a site certification agreement |
Fuel |
Kn lb/MMBtu |
#2 oil |
158.16 |
#4 oil |
160.96 |
#6 oil |
166.67 |
Lignite |
287.50 |
Sub-bituminous coal |
267.22 |
Bituminous coal, low volatility |
232.21 |
Bituminous coal, medium volatility |
241.60 |
Bituminous coal, high volatility |
262.38 |
Natural gas |
117.6 |
Propane |
136.61 |
Butane |
139.38 |
Petroleum coke |
242.91 |
Coal coke |
243.1 |
Other fossil fuels |
Calculate based on carbon content of the fossil fuel and application of the gross heat content (higher heating value) of the fuel |
Nonfossil fuels |
00.00 |
(2) Step 2 - Insert the annual CO2 rate to determine the total carbon dioxide emissions to be mitigated. The formula below includes specifications that are part of the total carbon dioxide definition:
Total CO2 Emissions = CO2rate x 30 x 0.6 |
(3) Step 3 - Determine and apply the cogeneration credit (if any). Where the cogeneration unit or facility qualifies for cogeneration credit, the cogeneration credit is the annual CO2 emission rate (in metric tons per year) and is calculated as shown below or similar method:
CO2credit |
= |
Hs |
x (Ka) / n |
2204.6 |
where:
CO2credit |
= |
The annual CO2 credit for cogeneration in metric tons/year. |
Hs |
= |
Annual heat energy supplied by the cogeneration plant to the "steam host" per the contract or other binding obligation/agreement between the parties in MMBtu/yr as substantiated by an engineering analysis. |
Ka |
= |
The time weighted average CO2 emission rate constant for the cogeneration plant in lb CO2/MMBtu supplied. The time-weighted average is calculated similarly to the above method described in subsection (1) of this section. |
n |
= |
Efficiency of new boiler that would provide the same quantity of thermal energy. Assume n = 0.85 unless applicant provides information supporting a different value. |
Calculate the metric tons of the cogeneration credit over the 30 year period.
Cogeneration Credit = CO2credit x 30 |
(4) Step 4 - Apply the mitigation factor.
Mitigation Quantity = Total CO2 Emissions x 0.2 - Cogeneration Credit |
where:
Mitigation quantity |
= |
The total CO2 emissions to be mitigated in metric tons. |
CO2rate |
= |
The annual maximum CO2 emissions from the generating facility in tons/year. |
0.2 |
= |
The mitigation factor in RCW 80.70.020(4). |
(5) Additional restrictions for modifications to an existing facility not involving installation of new generating units. The quantity of CO2 to be mitigated is calculated by the same methods used for the new generating units with the following restrictions:
Statutory Authority: Chapters 80.70 and 80.80 RCW and RCW 80.50.040. 08-14-064, § 463-80-050, filed 6/25/08, effective 7/26/08.