THE LIGHTWAVE BLOG
A place to review and voice opinion and
insight on the development of environments
28 February, 2018
Energy Efficiency, Thermal Comfort and Housing for older citizens
Many of us are well aware of the global phenomena taking place in world demographics and the structural ageing of the population. Indeed Bernard Bernanke, former Governor of the US Federal Reserve Bank stated “In the coming decades, many forces will shape our economy and our society, but in all likelihood, no single factor will have as pervasive an effect as the ageing of our population”
This population shift entails significant health, social and economic issues at all levels. At the design and building level, creating environments for older people will often require us to adopt different approaches to address the different needs of elderly people, and in particular, designs will need to respond to the degenerative effects of ageing.
I was recently pleased to discover a research paper that studied the energy efficiency of an aged care project that was designed by Lightwave. The paper examined the interplay between housing for older people, energy efficiency, energy consumption and thermal comfort. While it may seem a somewhat innocuous topic, it is highly relevant because morbidity and mortality rates are impacted by thermal comfort. Older people do not judge temperature as well as younger people. Older people, particularly those with multiple co-morbities (multiple chronic conditions) are often less able to recognise higher temperatures which is a result of poor thermoregulation. They are also and often less able to protect themselves from extreme temperatures by making necessary adjustments, such as putting on warmer clothes, turning on the air conditioner, or opening a door for more breeze.
The study, headed by Dr Wendy Miller of QUT, claimed that high temperatures for extended periods of time can have significant impacts on health. More people in Australia die from heatwaves than from floods and cyclones! Additionally, modern aged care environments are moving away from the medical care model to that of a wellness based care delivery method. In such a model, the thermal comfort of residents will be important contribution to the entire well-being of residents.
The facility subject to the investigation is located on the Southern outskirts of Brisbane and consists of 110 one and two bedroom apartments. The study reviewed the electricity consumption data for some 3.5 years. Additionally 11 apartments had sensors installed to the bedrooms, bathroom, living area and outdoor patio. The sensors recorded the temperature every 30 minutes. The temperatures of the apartments were recorded while they were both occupied and unoccupied. As with all scientific study, progress is slow, however a number of key correlations were identified and a number of observations were made by the research team that are of interest. They include:
- Energy consumption per single person household was only 79% of what is considered to be the standard of a low energy consumption household
- Apartments directly under an exposed roof had higher energy consumption than apartments below another apartment
- No correlation was found in relation to apartment size and energy consumption, only an observation that the larger units tended to consume less energy per square metre than smaller apartments
- Clear evidence that electricity consumption increased in the months of February (summer peak) and July (winter)
The results of the temperature readings shed similar insights
- Consistently lower temperatures were recorded in lower floor apartments. Lower floor apartments with exactly the same floor plan and orientation as upper level apartments recorded temperature readings of 25-27 degrees Celsius, while the upper levels recorded averages of 26 -29 degrees Celsius
- Balconies that faced west displayed temperatures during the summer months that make them unusable, regardless of what level of the building they were on.
- The apartments that displayed average temperatures of 25-27 did not vary whether they were occupied or vacant, while the temperatures of the apartments with the 26-29 degree readings indicated that residents were operating the air conditioners regularly to modify the temperature. This data provides confirmation that an apartment with appropriate thermal comfort levels requires less action by an elderly and frail resident to manage their comfort.
Dr Miller provides a summary of the results in the paper and initiates a number of discussion points and their policy implications. She proposes that while many health protection regulations apply in aged care, thermal performance of a building is not considered as part of a residents health. An argument is presented that that the impact of energy efficiency on internal temperatures needs to be fully understood so that strategies to adjust and manage routines in heat waves can be executed and that higher thermal performance standards for aged care should be implemented.
Miller, W., Vine, D., Amin, Z., 2016. Energy Efficiency of housing for older citizens: Does it matter? Energy Policy 101, 216-224. http://www.sciencedirect.com/science/article/pii/S0301421516306553