Smart-ready service C-2b · Cooling
Sequencing of different cooling generators
In short
- 1This page describes the smart-ready service C-2b, which concerns sequencing across multiple chiller units.
- 2The service is part of the Cooling domain within the Smart Readiness Indicator (SRI).
- 3There are five functionality levels, from 0 to 4, ranging from fixed operating hours to sequencing with external grid signals.
The levels
Level 0
Priorities only based on running times
Level 1
Fixed sequencing based on loads only: e.g. depending on the generators characteristics such as absorption chiller vs. centrifugal chiller
Level 2
Dynamic priorities based on generator efficiency and characteristics (e.g. availability of free cooling)
Level 3
Load prediction based sequencing: the sequence is based on e.g. COP and available power of a device and the predicted required power
Level 4
Sequencing based on dynamic priority list, including external signals from grid
What is sequencing across chiller units?
Many buildings with cooling systems use multiple chiller units in parallel, for example an absorption chiller and a centrifugal chiller. The order in which these units are activated determines how efficiently the system operates as a whole.
The smart-ready service C-2b assesses how intelligently a building automation and control system (BACS) determines this sequence. This is one of the smart-ready services within the Cooling domain in the Smart Readiness Indicator (SRI) methodology.
What functionality levels exist?
The SRI methodology defines five levels for this service, from 0 to 4. Each level represents a higher degree of intelligence in system control.
- Level 0: priorities based solely on operating hours.
- Level 1: fixed sequence based on load, for example determined by the characteristics of the chiller units.
- Level 2: dynamic priorities based on efficiency and characteristics, such as availability of free cooling.
- Level 3: sequencing based on load forecasting, using the coefficient of performance and predicted required capacity.
- Level 4: sequencing based on a dynamic priority list, including external signals from the electricity grid.
This service does not fall under method A, the simplified assessment method. It is only included in method B, the full methodology covering 54 smart-ready services.
Why does this service count towards the SRI score?
The SRI assesses buildings against seven impact criteria, including energy efficiency and grid flexibility. A higher level of sequencing can contribute to multiple impact criteria.
For example: level 4 takes into account signals from the electricity grid. This aligns with the impact criterion that rewards grid flexibility, potentially improving the building's class within the seven SRI classes.
Relevant for these building types
Next step
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