EXERGY Real-time Efficiency Analysis for Power Stations.

EXERGY

Real-time Efficiency Analysis for Power Stations

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The issue

• You need the ability to detect and diagnose efficiency problems in a thermal power station.

• You need your operators to be able to react to the diagnoses and restore the unit to a higher efficiency.

• This can add significantly to the operational profits of the station and result in lower CO2 emissions.

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EXERGY Real-time Efficiency analysis

Less Fuel = Less CO2 = More profit

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What is EXERGY?

EXERGY is a tool for detecting and diagnosing efficiency problems in thermodynamic processes

EXERGY saves operating costs. It has a unique ability to detect problems, diagnose causes and recommend remedial actions. It also allows operators to prioritise problems by providing an estimated cost per hour of the problem.

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What is EXERGY?

• EXERGY is the ONLY software available for continuous efficiency monitoring that is based on sound physics.

• EXERGY gives you continuous online efficiency monitoring

• EXERGY lets you pinpoint efficiency losses • EXERGY delivers instant reporting and diagnostics • EXERGY finds the root cause of problems, automatically

• EXERGY is the only software that calculates 2nd Law efficiency for your power station processes. It allows trending of component efficiencies and drill-downs to locate sources of problems .

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How EXERGY works: Background

• Plant efficiency management in the first instance is concerned with the Heat Rate, a 1st Law measure of efficiency.

• Ultimately a plant wants to produce as much output for the least expenditure of fuel.

• When plant efficiency deteriorates, either through incorrect operation, sudden failure in a component or through gradual loss of condition, the challenge is to find the cause and then cost the value of repairs.

• 1st Law measures of component efficiency are not useful for this analysis.

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How EXERGY works: Background

• In contrast, 2nd efficiency measures are ideally suited for this task.

• Exergy (availability) losses are additive (i.e. the total exergy loss for the plant is the sum of all the component losses), enabling attribution of the losses to plant components.

• The plant is modelled as a hierarchy of components, starting with entire plant. Losses can be tracked from top level of the plant to individual components.

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How EXERGY works: Background

• Entropy is additive• Entropy (and Exergy) is not a conserved quantity• Unit heatrate trend correlates exactly with Exergy loss

trend• These properties enable a quantitative method for

determining the root cause of heat rate excursions. • The resultant diagnostics procedure is valid both for

short term ( real time) and long term.

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Thermal Plant Efficiency

• The plant state at commissioning should be optimal

• Variance from optimal due to:

– Gradual deterioration of components

– Failure of components

– Sub-optimal/incorrect operation

• EXERGY detects the root cause of any efficiency loss.• Alarms when efficiency excursions occur with operating

recommendations

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EXERGY alarms

• Efficiency excursions result in alarms

• Alarms go to:

– Email if desired.

– Client PCs

– A central database

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Example Exergy alarm

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Exergy Alarm Analysis

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An example EXERGY audit: Bayeswater Station, NSW

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EXERGY audit as it happened, Bayeswater

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Exergy audit as it happened, Bayeswater

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Real Measurements, Bayeswater

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Overview of Exergy Components

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EXERGY installation

• Installs on MS Windows Server

• Interfaces with OsiSoft PI

– But custom interfaces can be used instead

– Reads instrumentation & writes back results

• Communicates with clients over TCP/IP network

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Contact us

• [email protected]

• www.powerstationefficiency.com