This document specifies methods for measuring, evaluating and reporting the performance of post-combustion CO2 capture (PCC) integrated with a power plant, and which separates CO2 from the power plant flue gas in preparation for subsequent transportation and geological storage. In particular, it provides a common methodology to calculate specific key performance indicators for the PCC plant, requiring the definition of the boundaries of a typical system and the measurements needed to determine the KPIs.
This document covers thermal power plants burning carbonaceous fuels, such as coal, oil, natural gas and biomass-derived fuels, which are producing CO2 from boilers or gas turbines, and are integrated with CO2 capture.
The PCC technologies covered by this document are those based on chemical absorption using reactive liquids, such as aqueous amine solutions, potassium carbonate solutions, and aqueous ammonia. Other PCC concepts based on different principles (e.g. adsorption, membranes, cryogenic) are not covered. The PCC plant can be installed for treatment of the full volume of flue gas from the power plant or a fraction of the total (i.e. a slip stream). Captured CO2 is processed in a compression or liquefaction step as determined by the conditions for transportation and storage.
The KPIs considered in this document are the following:
a) Specific thermal energy consumption (STEC);
b) Specific electrical energy consumption (SEC);
c) Specific equivalent electrical energy consumption (SEEC);
d) Specific reduction in CO2 emissions (SRCE);
e) Specific absorbent consumption (SAC) and specific chemical consumption (SCC).
The calculations are based on measurements at the boundaries of the considered system, particularly of energy and utilities consumption. The integrated system includes the definition of interfaces between the PCC plant and the power plant.
This document includes the following items:
— The system boundary which defines the boundaries of the PCC plant and identifies which streams of energy and mass are crossing these boundaries to help power plant operators identify the key streams that are applicable for their particular case.
— Basic PCC plant performance which defines the parameters that describe the basic performance of the PCC plant.
— Definition of utilities and consumption calculation which lists the utility measurements required and provides guidance on how to convert utility measurements into the values required for the KPIs.
— Guiding principles - Basis for PCC plant performance assessment which describes all guidelines to prepare, set-up and conduct the tests.
— Instruments and measurement methods which lists the standards available for the relevant measurements and considerations to take into account when applying measurement methods to PCC plants.
— Evaluation of key performance indicators which specifies the set of KPIs to be determined and their calculation methods to provide a common way of reporting them.
This document does not provide guidelines for benchmarking, comparing or assessing KPIs of different technologies or different PCC projects.
NOTE For the purposes of this document, thermal energy and electric energy are expressed by the unit of J (Joule) and Wh (Watt hour) respectively unless otherwise noted, with a prefix of International System of Units (SI) if necessary. (1 J = 1 W·s, 1 Wh = 1 W·h = 3 600 J).