Industry Friends of Low Carbon Living Forum 2017

Professor Frank Bruno

Research Professor, University of South Australia

Thermal Energy Storage and Applications

Storing Electricity for Cooling of Heating

Grid

Solar PV

Cooling

or

heating

Cooling or heating plant

Cooling or heating plantThermal Storage

battery

Energy Storage for Solar Power Plants

Thermal StoragebatteryGridSolar field

Powerblock

Conventional Thermal Storage

Hot water storage for district heating in Austria Ice banks for off peak

thermal storage in US

Hot

Water

What are Phase Change Materials (PCMs)

Store energy by changing from a solid to a liquid.

Ice is the traditional PCM

Energy to freeze (energy released) = Raising water by 80 oC

PCMs range from –100 to > 1400 oC

saltice

Thermal Energy Storage Tanks

Coil-in-tank

PCM in containers

Low cost containment

No additives required for supercooling

Readily-available non-toxic commercial grade salts.

High compactness factor

Traditional

Volume Reduction with PCMs

Cold liquid

thermal storage

PCM thermal storage

Energy Storage Economics

Li ion battery storage: 760 - 1800 $/kWhr electric (installed)

Traditional thermal storage for air conditioning: 100 – 400 $/kWhr electric

Traditional hot water storage: 140 $/kWhr electric

PCM thermal storage for refrigeration: 200 $/kWhr electric

Advantages of Thermal Energy Storage over Batteries

Cheaper

Longer life (batteries typically 10 to 15 years, thermal storage up to 30 years)

Thermal storage systems generally 100% recyclable

Can operate at higher ambient temperatures

Higher power capacity (kW)

Provides backup when heating or cooling generating equipment fails.

PCM Refrigeration System

PCM tanks

Cold Rooms

➢ 90 kWe Refrigeration system

➢ 1.1 MWhrse thermal storage (1% floor area)

Integrated renewable energy with thermal storage

Solar PV

Cold Room

Thermal Storage

Refrigeration

Electricity Grid

Battery

CONCLUSIONS

Thermal storage generally better than batteries for storing heat or cooling.

Many applications of thermal energy storage.

Thermal energy storage can save energy consumed and cost.

Thermal energy storage is one of many energy storage technologies that can increase the

uptake of renewable energy.