Small-scale PHES DemonstrationBrittany Tom, Southwest Research Institute

Bringing the Brayton Battery to life:

Solving system integration and operation challenges

Total project cost: $2.5M

Length 27 mo.

Project Vision

The Concept: Pumped Heat Energy Storage (PHES)

Charge Mode: Heat Pump Discharge Mode: Heat Engine

Charge

Compressor

Charge

Turbine

Hot Heat

Exchanger

Cold Heat

Exchanger

Q

Q

Discharge

Compressor

Discharge

Turbine

Hot Heat

Exchanger

Cold Heat

Exchanger

Q

Q

Cold Source Tank

Hot Storage TankHot Source Tank

Cold Storage Tank Cold Source Tank

Hot Storage TankHot Source Tank

Cold Storage Tank

WorkinWorkout

1

The Team: Southwest Research Institute (SwRI)

▸ Independent, nonprofit applied research and development organization founded in 1947

– Nine technical divisions

– 2,800 staff

▸ Machinery Department

– 60 engineers/ technicians

– Design, Analysis and Testing

– Turbomachinery

– Thermodynamic cycle

– Fluid/Thermal Systems

– Rotordynamics

– Mechanical Systems (bearings, seals, etc.)

2

2.1 Miles

1.2

Mile

s

The Team: Machinery Department Test Facilities

3

Multiphase Machinery

Laboratory Turbomachinery Laboratory

Gas Turbine Laboratory

Recip

Compression

Laboratory

‣ Advance PHES from concept to a kW-scale system demonstration

– TRL 2 TRL 4

‣ Focus on system operation and integration

‣ Performance data gathered during testing to verify system model

– Scale to predict full scale performance (10 MWe, 10 hrs at rated power)

Project Overview

4

Procurement and Assembly

Design Phase

Commissioning and Test

9 months

9 months

9 months

• Develop steady state and

transient models

• Define control strategies

• Turbomachinery Design

• Balance of Plant Design

• Continue refining

system model

• Initial cost analysis on

full scale control

system

• Demonstrate system startup,

shutdown, mode change

• Demonstrate control of efficient

closed loop system

Challenges and Potential Partnerships

▸ System Operation

– First implementation may have unknown unknowns

– Closed cycle operation

• Startup, shutdown, mode switch, bootstrap

– Uncertain system design

▸ Control Strategy and Transient Model

– Optimizing design space for efficient operation

– Tuning the controls for optimized performance

▸ In discussions with potential project partners

5

RTE

RT

E

Charge PRCold Storage

Temp

Hot Storage

Temp

Charg

e P

RC

old

Sto

rage

Tem

p

Hot

Sto

rage

Tem

p