small-scale phes demonstration
TRANSCRIPT
Small-Scale PHES Demonstration
Team Members: SwRI & Malta Inc.
PI: Natalie Smith, SwRI
Project Vision
Total project cost: $2.5M
Current Q / Total Project Qs Q9 / Q12
Bringing the Brayton Battery to life:
Solving system integration and operation challenges
Energy Summit
May 24-27, 2021
The Concept: Pumped Heat Energy Storage (PHES)
PHES Value Proposition
‣ 10+ hours of storage
‣ Separation of engine and storage
‣ Well-established component technologies
‣ Safer than other thermal-based ES technologies
‣ Potential for high round trip efficiency (RTE)
Technology Challenges
‣ First implementation challenges
‣ Control and operational unknowns
– Steady state
– Transients
‣ Charge compressor
‣ Reverse flow heat exchangers
1
Charge Mode Use excess energy to run heat pump
& store energy in hot and cold reservoirs
Discharge Mode Use thermal reservoirs to run heat engine
& generate power
The Concept: Pumped Heat Energy Storage (PHES)
2
Charge Mode Use excess energy to run heat pump
& store energy in hot and cold reservoirs
Discharge Mode Use thermal reservoirs to run heat engine
& generate power
340°C305°C
27°C12°C
340°C305°C
27°C12°C
The Team = SwRI + Malta+ Gas Turbine OEM
3
Benefiting government, industry and the public through innovative science and technology
Meet the Future of Energy Storage
kW-scale demonstration development, transient modelling, and testing
TEA and T2M
GT OEM
TEA
The Team = + + Gas Turbine OEM
4
Turbomachinery Mechanical Design
PM, Controls, Aero Cycle Optimization & Transient Modelling
TEA and T2M
Aaron Rimpel Josh Just Tommy Kerr, Ph.D.
Michael MarshallBrittany TomNatalie Smith, Ph.D.
Thomas Revak
Balance of Plant
George Khawly
Ben Bollinger, Ph.D.
GT OEMTEA
John Klaerner
Project Objectives to Address Technology Challenges
‣ Understand limitations of operational modes
– Steady state operation
– Startup, shutdown, mode switch
– Validation data for transient analysis
– Address first implementation challenges
‣ kW-scale Demonstration Facility
– Lower cost and lower risk test
– Predicted RTE = 10%
– Storage capacity for 1 hour operation charge/discharge
– Discharge Mode generates 5 kW
– 200 kW thermal
5
Demonstrate operation and verify system control strategies
of a closed air Brayton PHES at laboratory scale
TRL 2 TRL 4
Cycle Analysis Facility Design Procurement Transient Analysis Assembly Commission Test
Results: Cycle Optimization from Full- to Small-Scale
6
Full-scale: Higher temperature chloride salts up to approximately 800°C & improved compressor efficiency allow a pathway to greater than 60% RTE
Small-scale:
‣ To minimize costs and risk, several cycle condition compromises were implemented
60% High temperature salts and improved component efficiencies
48.9% Full-scale system with current technologies
24% Small-scale turbomachinery efficiencies
10% Storage media & temperature limits
‣ NPSS model accounts for turbomachinery maps, HX and valve performance, piping losses and thermal mass
‣ Optimizations with specified machinery and additional limitations resulted in
‣ lower pressure ratios
‣ lower overall performance Tom, Smith, McClung, 2020, “Cycle Considerations forthe Conceptual Design of a PHES,” GT2020-15657.
Results: COTS to Custom Turbomachinery
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‣ Initial plan: COTS machinery with minor redesigns
‣ Turbocharger sized for application
‣ Issue: Ease of ‘simple’ modification while maintaining mechanical integrity for required steady state and transient operation
‣ Result: Custom-designed turbocompressors
‣ Thermal protection provisions
‣ Rotordynamic integrity
‣ Thrust balance
Results: Transient Considerations from Modelling to Operation‣ Transient Considerations
– Equipment safety (rotordynamics, thermal, stall)
– Transient length
– Sequencing
• Machinery ramps
• Storage media
– Performance and storage media usage
‣ Charge Mode Start-up
– Compressor recycle
• Required for surge protection
• Overheating concerns with hot recycle
– Storage media and machinery ramping sequencing
– Example consideration: From ambient conditions with warm oil tanks and ambient coolant tanks, the heat transfer directions will be initially incorrect
Challenges and Potential Partnerships‣ Challenges & Risks:
– COTS Hardware:
• Closing the cycle with COTS hardware while ensuring controllability and optimized system performance
• Complete redesign of COTS hardware to de-risk demonstration operation
– Fast Transients:
• Enabling optimal transient time while protecting hardware
• Extensive transient cycle modelling has informed a phased test matrix
– Next: What does actual implementation look like?
‣ Collaboration:
– Follow-on projects to progress PHES development using our Energy Storage Test Facility including different storage media, conditions, and working fluids
Technology-to-Market
‣ Final Goal: Full-scale system (10 or 100 MW)
demonstration and deployment
‣ Status: Approximately 2024 for a 100 MW system
‣ Accelerate Development:
– Market readiness supported by improved policy and regulation
– Continued iterative component and system improvements to progress the SOA
• Charge compressor
• Molten salt technology
‣ Potential First Markets:
– Power plants in areas with high renewable penetration
Small-Scale PHES Demo
Objective: Demonstrate operation and verify control strategies of a closed air Brayton PHES at lab scale
Outcomes:
‣ Steady state and transient operation data to inform full-scale system design
– Ambient effects
– Sequencing considerations
‣ Dedicated energy storage test facility
– Predicted RTE = 10%
– Storage capacity for 1 hour steady state operation
– 50 kWth
– Discharge Mode generates 5 kW
Cycle Analysis Facility Design Procurement Transient Analysis Assembly Commission Test
N
Control Room
Sept 2021 Dec 2021