Energy efficiency measures can support good physical and mental health primarily by creating healthy indoor living environments with healthy air temperatures, humidity levels, noise levels, and improved air quality.

The World Health Organization estimates that globally air pollution causes about 3 million premature deaths a year,1 making air pollution a significant environmental risk. Energy efficiency measures targeting indoor and outdoor air quality can have major impacts for global health.

Recent evidence shows that chronic thermal discomfort and fuel poverty also have negative mental health impacts (anxiety, stress, and depression). Energy efficiency improvements targeting fuel poverty can therefore improve mental well-being. Energy efficiency’s impact on mental health may be enhanced if combined with financial support mechanisms2  and strong community engagement.3

A household is generally defined as being in fuel poverty if more than a certain percent of its annual income (typically 10%) is spent on energy. Such a proportional energy spend would tend to suggest difficulties in affording adequate levels of comfort. Most often, fuel poverty tends to be caused by a combination of low income, poor housing quality and high energy costs. Fuel poverty is also strongly associated with sub-optimal physical and mental health. Energy efficiency retrofits of low-income housing can offer a solution that permanently makes comfort more affordable.

Several IEA member countries, including Australia, Ireland, New Zealand, the United States and the United Kingdom have targeted energy efficiency policies to address fuel poverty with positive results. A study using data from New Zealand’s Warm Up NZ: Heat Smart programme evaluation indicated significantly higher monetised benefits among families on low to modest incomes of USD 519 per year after the retrofitting compared to USD 183 for higher-income families.4

Governments use a range of policies to mitigate fuel poverty, including support payments for fuel costs, social tariffs (subsidies) on energy prices, grant programmes for expenses associated with energy efficiency upgrades, or free retrofit programmes for low-income households. To date, programmes for energy efficiency retrofitting of low-income housing have delivered the greatest benefits, with health improvements representing as much as 75% of the total return on the investment for these interventions.5

Fuel poverty is also strongly associated with sub-optimal mental health, in part because of the financial stress of coping with high energy bills and debt. Energy efficiency measures that improve the affordability of energy bills in low-income homes can have a measurable effect on improving mental well-being (e.g. happiness and coping) and preventing mental disorders (e.g. anxiety and borderline depression).6

While energy efficiency measures in diverse sectors show potential to deliver health and well-being improvements, measures targeting buildings are often easier to verify. Energy efficiency retrofits in buildings (e.g. insulation retrofits and weatherisation programmes) create conditions that support improved occupant health and well-being, particularly among vulnerable groups. The potential benefits of energy efficiency measures include improved physical health such as reduced symptoms of respiratory and cardiovascular conditions, rheumatism, arthritis and allergies, as well as fewer injuries. In cold climates, energy efficiency improvements can lower rates of excess winter mortality while in hot climates; they can help reduce the risk of dehydration and negative health impacts.

The health benefits of energy efficient buildings can be realised in both homes and workplaces. A Singaporean study found that people working in energy efficient buildings are less likely to suffer from fatigue, headaches or skin irritations. Improving the health of workers could in turn have significant implications for workplace productivity.

Measures to improve insulation, heating and ventilation systems can have positive impacts on air quality, reducing respiratory and cardiovascular diseases, and allergies. They also drive significant and consistent mental health improvements.7

Thermal quality refers to whether the indoor temperature is comfortable and healthy. While most evidence relates to the impact of cold environments, over-heating can also damage health through dehydration.8 Energy efficiency retrofit programmes that include installing insulation are shown to enable occupants to raise indoor air temperatures to healthy levels. Temperature has a large impact on employee productivity and comfort in the work place. All of these measures, particularly ventilation, play a role in reducing indoor dampness and the associated build-up of mould that exacerbates many health conditions.9