The presentation discusses how utilizing thermal potential through geoexchange systems can enhance energy efficiency and productivity. Thermal potential involves using heat sources and sinks from the local environment for heating and cooling. Geoexchange transfers heat between the earth and buildings through ground heat exchangers. Case studies show geoexchange systems at St Peters College and Geoscience Australia reduced energy usage by over 50% and provided significant cost savings. Optimizing thermal energy storage and control strategies can better integrate renewable thermal and electrical energy sources to maximize efficiency.
Thermal Potential's Role in Boosting Energy Efficiency
1. The Role of Thermal Potential in Enhancing
Energy Efficiency / Productivity
Presented by:
Yale Carden
GeoExchange Australia Pty Ltd
27 June 2018
2. Presentation Overview
Start With Why
What is Thermal Potential?
Enhancing Energy Efficiency / Productivity
Geoexchange 101
Case Studies
Conclusions
The Role of Thermal Potential in Enhancing Energy Efficiency / Productivity
3. The First Why
‘…we must consider environmental sustainability as one of the world’s greatest challenges.’
‘…must promote sustainability through educational programs and school operations.’
‘We must focus on minimising our carbon emissions and environmental footprint through
energy, water consumption and waste recycling.’
The Role of Thermal Potential in Enhancing Energy Efficiency / Productivity
4. The Other Why: Cost and Performance
Operations:
Existing system becoming old and maintenance increasing
Cost:
Increasingly expensive to operate
Comfort:
Uncontrollably warm in summer months
The Role of Thermal Potential in Enhancing Energy Efficiency / Productivity
5. Parallels with Energy Sector
Energy Sector HVAC Sector
Local Energy Potential Local Thermal Potential
Renewable Sources Renewable Sources
Decreasing Demand Decreasing Demand
Energy Storage Thermal Storage
Controls: Smart Meters Controls: Optimised Strategies
Decentralising Systems Centralising Systems
The Role of Thermal Potential in Enhancing Energy Efficiency / Productivity
8. Typical Commercial Heating / Cooling System
Cooling Towers Boilers
Ambient air
Use water
Legionella control
Burn fossil fuels
Non-renewable
Alternative gas supplies
The Role of Thermal Potential in Enhancing Energy Efficiency / Productivity
9. What is Thermal Potential?
Demand Management Tool – the (forgotten) half of the energy equation
Thermal is energy too!
Thermal energy can also be renewable – not just about burning gas and fossil fuels
Thermal potential consists of:
Heat sources (heating)
Heat sinks (cooling)
Thermal energy storage, including phase change materials
Multiple thermal sources in the built environment
The Role of Thermal Potential in Enhancing Energy Efficiency / Productivity
10. Integrating to Enhance Energy Productivity
Renewable (Electrical) Energy
Renewable (Thermal) Energy
Can we integrate the two and enhance energy productivity?
Greatest $ output for smallest kW input BECOMES
Greatest $ / kW output for smallest carbon input
Source: www.sbrc.uow.edu.au/sbrcbuilding/index.html
The Role of Thermal Potential in Enhancing Energy Efficiency / Productivity
11. Geoexchange 101: The Basics
The Role of Thermal Potential in Enhancing Energy Efficiency / Productivity
12. Geoexchange 101: The Basics
Transfers heat from the earth into the building in winter (earth as heat source)
Transfers heat from the building into the ground in summer (earth as heat sink)
Geoexchange or low temperature geothermal NOT ‘hot rocks’
Solar radiation not heat from the Earth’s crust
The Role of Thermal Potential in Enhancing Energy Efficiency / Productivity
13. The Geoexchange Cooling Cycle
The Role of Thermal Potential in Enhancing Energy Efficiency / Productivity
17 C
40 C
14. The Geoexchange Heating Cycle
The Role of Thermal Potential in Enhancing Energy Efficiency / Productivity
17 C
-5 C
16. Energy Piles
The Role of Thermal Potential in Enhancing Energy Efficiency / Productivity
17. Sewer Heat Recovery
Also includes wastewater / treated effluent
Not just heating – cooling also possible
20-25C heat source / sink is common
Match ‘water’ flow to heating / cooling requirements
Local projects using treated effluent:
Hobart Aquatic Centre, Hobart
Grand Chancellor Hotel, Hobart
The Role of Thermal Potential in Enhancing Energy Efficiency / Productivity
19. Thermal Energy Storage
0
5000
10000
15000
20000
25000
30000
35000
40000
0 2 4 6 8 10 12
TotalLoads(kWhrs)
Time (Months)
Cooling (kWhrs)
Heating (kWhrs)
Short term storage:
Simultaneous or diurnal
Annual storage
Heat
Rejection
Heat
Extraction
Heat
Rejection
The Role of Thermal Potential in Enhancing Energy Efficiency / Productivity
20. GSHPs: Water to Water / Reversible Chillers (Pool)
The Role of Thermal Potential in Enhancing Energy Efficiency / Productivity
21. GSHPs: Water to Air (Ducted) Units
The Role of Thermal Potential in Enhancing Energy Efficiency / Productivity
22. Case Study: St Peters College
Existing system uses ambient air
Thermal potential approach considered the following:
Gas;
Ambient air (used for heat recovery);
Ground with vertical borehole GHX;
Ground with horizontal GHX;
River water under existing irrigation license;
Treated effluent.
River water was Client preference. However, logistical and future-proofing issues;
Vertical GHX preferred over horizontal GHX
Minimise impact on sport fields;
Enable future expansion of system.
The Role of Thermal Potential in Enhancing Energy Efficiency / Productivity
23. The Ground Heat Exchanger
The Role of Thermal Potential in Enhancing Energy Efficiency / Productivity
24. The Ground Source Heat Pumps
2 x water to water / reversible chillers
6 x various water to air (ducted) GSHPs
Heat Recovery System
Variable Speed Pumps
The Role of Thermal Potential in Enhancing Energy Efficiency / Productivity
25. Energy Efficiency Opportunities
56%
8%
3%
25%
8%
Energy Efficiency Opportunities
Geoexchange Plant Upgrade Fresh Air Heat Recovery Roof Pool Blanket Ducted GSHPs
The Role of Thermal Potential in Enhancing Energy Efficiency / Productivity
26. Case Study: RHBEEP - Tumut (Snowy) Shire Council
The Role of Thermal Potential in Enhancing Energy Efficiency / Productivity
27. Case Study: RHBEEP - Tumut (Snowy) Shire Council
Building energy savings: 80 % or $94 000 per annum
HVAC energy savings: 71 % or $85 000 per annum
Maintenance / tenancy savings: $80 000 per annum
Electricity demand reduction: 151 kVA (75 %) Geoexchange at 49 %
Annual GHG Reduction: 79 tCO2
Simple Payback: 7.6 years
Return on Investment: 11-12 %
The Role of Thermal Potential in Enhancing Energy Efficiency / Productivity
28. Case Study: Geoscience Australia
The Ground Heat Exchanger:
350 Boreholes
104 m deep
1.25” diameter polyethylene pipe
4.5 m spacings
Ground Source Heat Pumps:
220 x WaterFurnace water to air GSHPs: Premier2
2-speed compressor
3-speed fan
BMS connectivity
R22 refrigerant
The Role of Thermal Potential in Enhancing Energy Efficiency / Productivity
29. Case Study: Geoscience Australia
The Role of Thermal Potential in Enhancing Energy Efficiency / Productivity
30. Case Study: Geoscience Australia
The Role of Thermal Potential in Enhancing Energy Efficiency / Productivity
31. Case Study: Geoscience Australia
The Role of Thermal Potential in Enhancing Energy Efficiency / Productivity
32. Conclusions: Enhancing Energy Efficiency?
Create energy from renewable sources – use as efficiently as possible
Thermal is energy too…and it can be renewable
Identify local thermal potential
Can we use renewable (thermal) energy when renewable (electrical) energy is available?
Timing issues? Storage is the key – electrical or thermal
Optimised / Predictive Control Strategies
Canberra is ideal climate for the technology with great local case studies
The Role of Thermal Potential in Enhancing Energy Efficiency / Productivity
33. Thank you
Yale Carden
GeoExchange Australia Pty Ltd
Phone: 02 8404 4193
Email: ycarden@geoexchange.com.au
Website: www.geoexchange.com.au
The RHBEEP Project
www.tumut.nsw.gov.au/riverina-highlands-building-energy-efficient-project-rhbeep.aspx
Sustainable Buildings Research Centre, University of Wollongong
www.sbrc.uow.edu.au
The Role of Thermal Potential in Enhancing Energy Efficiency / Productivity
Editor's Notes
Reduced energy consumption, including peak loads. Thisenhances capability of local renewable energy generation to provide higherpercentage of overall energy usage;
Reduced water consumption through removal of cooling towers;
Removal of gas from site infrastructure as all heating / cooling is electrically powered. Once again this enhances potential of local renewable energy generation and ensures future flexibility with respect topower (ie not being limited by gas connection);
Dual use of existing utilities (eg use of low grade heat from sewer, wastewater, irrigation systemsetc for both heating / cooling).
Reduced energy consumption, including peak loads. Thisenhances capability of local renewable energy generation to provide higherpercentage of overall energy usage;
Reduced water consumption through removal of cooling towers;
Removal of gas from site infrastructure as all heating / cooling is electrically powered. Once again this enhances potential of local renewable energy generation and ensures future flexibility with respect topower (ie not being limited by gas connection);
Dual use of existing utilities (eg use of low grade heat from sewer, wastewater, irrigation systemsetc for both heating / cooling).
Reduced energy consumption, including peak loads. Thisenhances capability of local renewable energy generation to provide higherpercentage of overall energy usage;
Reduced water consumption through removal of cooling towers;
Removal of gas from site infrastructure as all heating / cooling is electrically powered. Once again this enhances potential of local renewable energy generation and ensures future flexibility with respect topower (ie not being limited by gas connection);
Dual use of existing utilities (eg use of low grade heat from sewer, wastewater, irrigation systemsetc for both heating / cooling).
Reduced energy consumption, including peak loads. Thisenhances capability of local renewable energy generation to provide higherpercentage of overall energy usage;
Reduced water consumption through removal of cooling towers;
Removal of gas from site infrastructure as all heating / cooling is electrically powered. Once again this enhances potential of local renewable energy generation and ensures future flexibility with respect topower (ie not being limited by gas connection);
Dual use of existing utilities (eg use of low grade heat from sewer, wastewater, irrigation systemsetc for both heating / cooling).
Reduced energy consumption, including peak loads. Thisenhances capability of local renewable energy generation to provide higherpercentage of overall energy usage;
Reduced water consumption through removal of cooling towers;
Removal of gas from site infrastructure as all heating / cooling is electrically powered. Once again this enhances potential of local renewable energy generation and ensures future flexibility with respect topower (ie not being limited by gas connection);
Dual use of existing utilities (eg use of low grade heat from sewer, wastewater, irrigation systemsetc for both heating / cooling).
Reduced energy consumption, including peak loads. Thisenhances capability of local renewable energy generation to provide higherpercentage of overall energy usage;
Reduced water consumption through removal of cooling towers;
Removal of gas from site infrastructure as all heating / cooling is electrically powered. Once again this enhances potential of local renewable energy generation and ensures future flexibility with respect topower (ie not being limited by gas connection);
Dual use of existing utilities (eg use of low grade heat from sewer, wastewater, irrigation systemsetc for both heating / cooling).