Improving energy efficiency means using less energy to achieve the same level of outcome.
Improving energy efficiency offers economic benefits, as it reduces energy consumption and thus energy expenditure. It also offers environmental benefits by reducing the environmental impacts associated with carbon-intensive energy sources such as electricity produced by coal-fired power stations.
Improvement in energy efficiency
Energy efficiency of Victorian public hospitals has been improving since 2005-06. The energy use in hospitals is influenced by many factors. The three currently used indicators to measure energy are intensity per floor area, per occupied bed-day (bed-day) and per separation.
Floor area figures collected by the department represent gross floor area and exclude carparking.
Bed-days and separations
Bed-days and separations are used as measures of hospital activity. Occupied bed-days (also known as patient days) are the number of days or part days for all patients who were admitted for an episode of care and who underwent separation. A separation is defined as ‘the formal process by which a hospital records the completion of an episode of treatment and/or care for an admitted patient’.
Figure E3 shows the change in energy intensity for Victorian public hospitals between 2005-06 and 2013-14. The figure shows an overall improvement in energy efficiency (reduction in energy intensity) across the portfolio.
Over this period, energy intensity relative to floor area and bed-days has reduced by about 10 and 8 per cent respectively, and energy intensity measured as energy consumption per separation has reduced by more than 22 per cent.
Figure E3: Change in Victorian public hospitals energy intensity (Source: AIMS)
Energy efficiency in Victorian public health services
Victorian public healthcare services have been implementing energy efficiency initiatives for more than 10 years. Some of the more common initiatives include:
- installing more efficient lighting such as LED
- installing lighting controls such as motion sensors in infrequently occupied rooms
- installing variable-speed drives for fans or pumps
- installing newer and more efficient air-conditioning
- installing air-conditioning controls such as time controllers that switch equipment off after hours
- improving the maintenance of building systems.
Examples of energy efficiency projects include:
- Austin Health installed variable-speed drivers and boiler optimisation systems, as well as energy-efficient lighting.
- West Gippsland Healthcare Group installed energy-efficient lights and a new building management system, replaced laundry equipment and upgraded its engineering infrastructure.
- Yarrawonga Health implemented energy-efficient lighting.
Energy efficiency is also incorporated in capital works projects, for example, the energy-efficient cooling and heating system at Wantirna Health.
Energy performance contacting
Energy performance contacting (EPC) is a contracting model, used extensively in the United States, to fund energy-efficiency and water-efficiency projects. The model uses guaranteed savings over a defined period (usually seven to eight years) to recoup the investment.
Energy efficiency benchmarks
Energy efficiency benchmarks allow organisations to measure how well they are managing their energy consumption. They allow for comparisons over time and comparisons with similar organisations.
Gigajoules per square metre
The ratio of annual energy consumption to floor area (gigajoules per square metre - GJ/m2) is the most commonly used benchmark for buildings. Analysis by the department has found that this metric is useful for monitoring year-on-year performance for an individual hospital or all public health services.
However, GJ/m2 is a poor measure for comparing energy performance between different hospitals, due to a very high variability in GJ/m2 values between similar hospitals.
Figure E4 shows notable spread in GJ/m2 values for similar hospitals. This high variability can be attributed to a wide range of factors but not necessarily to the way health services are managing their energy use.
Factors that are likely to explain this variability are whether the hospital:
- has a laundry
- has a co-generation system
- uses natural gas or electricity for cooling and heating
- uses much of the floor area for clinical activities.
Hospitals in the chart are grouped based on their service planning classification (type of health services delivered). The blue markers in the graph show the GJ/m2 values for all hospitals in the health portfolio.
The peer groups are ordered in accordance with the complexity of provided services. Tertiary hospitals (for example, Alfred Hospital) are providing the most complex services and rural hospitals (for example Yea and District Memorial Hospital) the least complex services.
The blue markers in the graph show the energy-intensity values for all hospitals in the health portfolio.
Gigajoules per square metre across hospitals
The graph shows high variability in GJ/m2 values across all types of hospitals. The graph also shows correlation between the type of hospital and the range of values; as expected GJ/m2 values are typically higher for hospitals delivering more complex services.
Figure E4: Range of energy intensity values (GJ/m2) for different types of hospitals.
Source: AIMS data for 2012-13.
National Australian Built Environment Rating System
The National Australian Built Environment Rating System (NABERS) is a rating scheme used by organisations to manage the environmental performance of their buildings. NABERS normalises energy consumption and floor area values to account for variability not related to energy performance. This allows comparison of different buildings. For example, in a five-star NABERS-rated office building, energy is managed more efficiently than in a four-star rated office.
A specific NABERS rating program that measures the environmental performance of hospitals is not currently available but is being actively considered.