Charles Sturt University – Energy Performance Contract (EPC Stage 2)
/year - Cost savings
kWh - Electricity savings
GJ/year - Natural gas savings
tonnes CO2-e/year - GHG reduction
// case study
In this case study
// Solutions
Overview
Following the success of EPC Stage 1, CSU partnered with Conservia once again for the second phase of energy upgrades at Truskett Library in the Bathurst Campus. EPC Stage 2 targeted central plant infrastructure and mechanical system enhancements.
// Challenge
Solution
Conservia focused on replacing aged, inefficient systems with high-efficiency, low-emissions alternatives while continuing the rollout of intelligent control and lighting systems.
// Solutions
Key Measures:
- Replacement of an obsolete R22 water-cooled chiller and cooling tower with a high-efficiency air-cooled chiller using R134a and VSD-equipped screw compressors
- Installation of a high-efficiency forced draft hot water heater with VSD-driven circulating pumps
- Replacement of the central AHUs with new systems featuring VSDs and high-efficiency motors
- VSD and motor upgrades on additional AHUs, chilled water pumps, and hot water pumps
- BMS enhancements with energy-efficient logic including optimum start/stop, temperature resets, and CO2-based demand ventilation
- Installation of LED panel lighting in Level 3 offices and Level 5 bookshelves, replacing outdated fluorescent fittings
// Challenge
Results
The project delivered strong performance across energy, financial, and environmental metrics. Annual savings included 813,548 kWh of electricity, 4,106 GJ of natural gas, and 740 kL of water, with natural gas savings exceeding the guarantee by 93%. Financially, the $1.1M investment generated $176,831/year in cost savings, outperforming the guaranteed $157,108/year by 12.6% ($19,723), with a 7-year payback period. Environmentally, it achieved a significant reduction of 1,077 tonnes CO₂-e/year in greenhouse gas emissions.
Energy and Gas Savings:
| Resource | Proposed Savings | Achieved Savings | % Over Target |
|---|---|---|---|
| Electricity | 111,570 kWh/year | 183,300 kWh/year | 64% |
| Natural Gas | 461 GJ/year | 480 GJ/year | 4% |
Financial Outcome:
| Metric | Value |
|---|---|
| Project Cost | ~$132,860 |
| Guaranteed Cost Savings | ~$18,480/year |
| Achieved Cost Savings | ~$26,554/year |
| Savings Over Guarantee | $8,074 (43%) |
| Simple Payback Period | 7.2 years |
Environmental Outcome:
| Metric | Proposed | Achieved | % Over Target |
|---|---|---|---|
| GHG Savings | 148 tonnes CO2-e/year | 211 tonnes CO2-e/year | 43% over |
// Challenge
highlights
- Cost savings: $26,554/year
- Electricity savings: 183,300 kWh/year
- Natural gas savings: 480 GJ/year
- GHG reduction: 211 tonnes CO2-e/year
