ShareJapanese households don’t make the most of reversible heat pumps
Despite a high market penetration, less than half of Japanese households use their reversible heat pumps for heating.
The heat pump market has expanded rapidly in the last decade thanks to decreased costs and policy incentives. Many stakeholders agree that heat pumps represent a key technology to reduce energy consumption and CO2 emissions in the residential sector. Global heat pump sales rose by 15% in 2021 and 11% in 2022. [1]
In Japan, the market penetration for reversible domestic heat pumps, which can be used for heating and air conditioning, was already at 90% by 2014. [2]
Less than half of Japanese households use their reversible heat pumps for heating
According to a survey commissioned by Panasonic amongst 10,000 participants aged in their 20s to 60s, 93.2% of households in Japan are equipped with at least one air conditioner. [3] Yet surprisingly, only 44.5% of the responders used their reversible equipment for heating.
The concern for electricity costs and a potential negative impact on the environment appear to be the main reasons for the reluctance of many Japanese households to rely on reversible heat pumps for heating. In many Japanese households (44.9%), heat pumps are perceived as more expensive to operate than fossil fuel heaters (i.e. oil stoves and fan heaters).
The elderly do not use their air conditioners during the summer.
Among the elderly, many refuse to turn on their air conditioners during summer heatwaves to avoid the cost. [4] Furthermore, studies have shown that thermal perception decreases with age, and older people often don’t realise when they are overheating or dehydrated. [5] In another survey conducted in Tokyo, people aged 65 or older made up 90% of heat-related fatalities. The majority unfortunately died indoors, due mostly to the fact they didn’t use an air conditioner. [6]
In response, the Japanese Environment Ministry adopted in May 2023 a 5-year plan aiming to halve heatstroke deaths by 2030. Measures include consumer information among the elderly, along with a “special heatstroke alert” based on wet bulb temperature, which takes into account humidity. The “special heatstroke alert” is likely to take effect by summer of 2024. [6]
Despite their energy-saving potential, the electricity required by heat pumps may add burden to the electricity grid during peaks in heat demand. The integration of thermal energy storage (TES) for demand side management is seen as an effective solution to cater for these fluctuations in electricity demand.
Access to air conditioning saved over 190,000 lives in 2019
In the 2022 report for the Lancet Countdown on health and climate change, the authors estimated the number of heat-related deaths averted thanks to air conditioning, especially among high-risk senior and elderly people.
Sources
[1] IEA. (2022a). The Future of Heat Pumps. https://www.iea.org/reports/the-future-of-heat-pumps
[2] Hideaki Maeyama. Market Report: Japan. (2020) Heat Pump & Thermal Storage Technology Center of Japan (HPTCJ). https://heatpumpingtechnologies.org/market-report-japan/
[3] https://bnnbreaking.com/world/japan/japanese-households-prefer-fossil-fuel-heaters-over-air-conditioners-panasonic-survey-reveals/
[4] https://japantoday.com/category/features/kuchikomi/seniors-dying-at-home-with-air-conditioners-off-why-don%27t-they-turn-them-on
[5] Liu, Meng, et al. "Air-conditioning usage behaviour of the elderly in caring home during the extremely hot summer period: An evidence in Chongqing." Building and Environment 244 (2023): 110828. https://doi.org/10.1016/j.buildenv.2023.110828
[6] https://www.japantimes.co.jp/environment/2023/07/30/climate-change/climate-change-heat-waves-aging-society/