# Heat wave cooling, health, and energy efficiency guidance > Live situation record from CLSTR: https://clstr.news/situations/heat-wave-home-cooling-guidance > Updated: 2026-09-08T23:37:00.000Z. Sources: 110. Developments: 20. As heat waves persist and El Niño effects drive demand for cooling, experts continue to refine guidance on passive cooling, ventilation, and energy efficiency. A central theme remains the superiority of external shading; architect Julia Ayuso recommends tools like ‘Alicante blinds’ to block radiation before it reaches the glass. Ventilation timing is critical, with experts advising opening windows only when outdoor air is cooler than indoor air. Regarding air conditioning, specialists recommend settings between 23°C and 25°C to optimize efficiency. Energy consultant Alex Bermudez notes that every degree lowered below the target can increase energy consumption by 6% to 8%, but suggests that running a unit throughout the night has a minimal impact on electricity bills, comparing the cost to ‘a single cup of coffee.’ In Brazil, experts from Energisa Rondônia add that regular filter cleaning and keeping doors and windows closed during operation are vital for efficiency. Other energy-saving habits include turning off fans in unoccupied rooms and consolidating the use of heavy appliances. While air conditioning provides life-saving benefits—a study in Nature Health indicates these systems prevent more than 5,000 heat-related deaths annually in the United States—they also contribute to the urban heat island effect by transferring heat from indoors to the outdoors. Innovative cooling alternatives also include dual-purpose systems, such as those in Zurich, where 20°C water flows through aluminum lamellas to cool air via fans. Experts suggest that underfloor, wall, or ceiling systems are often preferable to traditional radiators for effective cooling. ## Claims - The World Health Organization recommends training in climate-controlled spaces during heatwaves in its 'Heat and Health' guide. (corroborated by 4 sources) - Luis Enrique Conde, Technical Director of Clubs DiR, suggests prioritizing moderate intensity workouts during extreme heat. (corroborated by 4 sources) - Increasing time spent on warm-ups and cool-downs helps the body adapt to temperature changes. (corroborated by 4 sources) - Using a pool to finish a workout can help reduce body temperature and muscle fatigue. (corroborated by 4 sources) - Not all heat pumps are equally suitable for cooling; suitability depends on the system's technology and appropriate heating surfaces. (single source) - Active cooling is achieved via reversible heat pumps that reverse the cycle to move heat from indoors to outdoors. (single source) - Passive cooling uses heat exchangers to transfer building heat to cooler ground or groundwater, offering lower cooling capacity but higher energy efficiency. (single source) - A study commissioned by the Bauherren-Schutzbund identified the 10 most common errors in heat pump installation for new builds and renovations. (single source) - Heat pumps were the most commonly installed heating systems in 2025. (single source) - Using clay modules in ceilings can regulate temperature and humidity to provide cooling without traditional air conditioning. (single source) ## Timeline ### 2026-09-08: Air conditioning usage impacts public health and energy consumption While air conditioning prevents thousands of heat-related deaths annually, it contributes to urban heat and energy demand. Experts suggest efficiency habits to manage rising costs during heat waves. 2 sources. https://clstr.news/cluster/air-conditioning-usage-impacts-public-health-and-energy-consumption ### 2026-09-01: Home cooling strategies and air conditioning efficiency during heatwaves As heatwaves affect France, experts suggest cooling homes through strategic ventilation or efficient air conditioning use, recommending settings between 23°C and 25°C to minimize electricity costs. 4 sources. https://clstr.news/cluster/home-cooling-strategies-and-air-conditioning-efficiency-during-heatwaves ### 2026-08-31: Heat pumps and convectors offer efficient cooling alternatives New building technologies are utilizing heat pumps and specialized convectors to provide efficient cooling during summer months, offering an alternative to traditional air conditioning. 7 sources. https://clstr.news/cluster/heat-pumps-and-convectors-offer-efficient-cooling-alternatives ### 2026-08-28: Energy efficiency tips for using air conditioning during heatwaves Using inverter air conditioners efficiently involves maintaining moderate temperatures rather than frequent cycling. Setting lower temperatures does not speed up cooling and may increase energy consumption. 3 sources. https://clstr.news/cluster/energy-efficiency-tips-for-using-air-conditioning-during-heatwaves ### 2026-08-27: Heat pump technology offers cooling alternatives for summer heat Homeowners are utilizing heat pumps for active and passive cooling to combat rising summer temperatures, though experts warn of installation errors and emphasize the importance of proper planning. 4 sources. https://clstr.news/cluster/heat-pump-technology-offers-cooling-alternatives-for-summer-heat ### 2026-08-27: Architects recommend passive cooling and duct systems for efficiency Architects recommend prioritizing passive climate control, such as proper house orientation and insulation, alongside efficient air duct systems to manage summer heat and energy consumption. 4 sources. https://clstr.news/cluster/architects-recommend-passive-cooling-and-duct-systems-for-efficiency ### 2026-08-19: Cooling solutions range from portable fans to low-tech home strategies Options for managing heat include the portable, cordless Levoit Windi Mini Pro tower fan and low-tech methods like strategic ventilation, shading, and improved hydration. 3 sources. https://clstr.news/cluster/cooling-solutions-range-from-portable-fans-to-low-tech-home-strategies ### 2026-08-17: Heatwave safety and cooling strategies for homes and health Experts provide guidance on managing heatwaves through personal safety measures for vulnerable groups and passive cooling techniques for homes, such as strategic ventilation and solar protection. 9 sources. https://clstr.news/cluster/passive-cooling-methods-to-maintain-cool-homes-during-heatwaves ### 2026-08-17: Home cooling strategies: Experts advise on heat management and energy efficiency Experts share advice for summer heat management, including using external blinds, prioritizing west-facing window protection, and lowering shutters before 10:00 AM to save on energy costs. 9 sources. https://clstr.news/cluster/home-cooling-strategies-for-summer-heat ### 2026-08-15: Exterior solar protection for summer heat management To combat nighttime heat, architects recommend using exterior blinds during the day to block solar radiation before it enters the home, rather than relying on indoor curtains or fans. 6 sources. https://clstr.news/cluster/exterior-solar-protection-for-summer-heat-management ### 2026-08-14: Air conditioning efficiency: Expert tips to save energy and improve sleep Experts recommend setting air conditioners to 26-28°C and using fans to save electricity and improve sleep quality during hot weather. 11 sources. https://clstr.news/cluster/seasonal-lotus-stems-offer-nutrition-during-autumn-transition ### 2026-08-12: Summer heat management: Tips for ventilation and cooling Summer heat management tips include ventilating basements only when outdoor air is cooler to prevent mold and using fans effectively to improve airflow and cooling relief. 7 sources. https://clstr.news/cluster/summer-heat-management-tips-for-ventilation-and-cooling ### 2026-08-11: Energy efficiency tips to reduce summer cooling costs Experts suggest managing air conditioning settings, using fans, and installing window shades to maintain comfort and reduce high summer electricity bills during heatwaves. 20 sources. https://clstr.news/cluster/energy-efficiency-strategies-for-summer-cooling-and-electricity-savings ### 2026-08-08: Energy efficiency tips for household appliances during summer heatwaves Experts recommend setting air conditioners to approximately 25.5°C, optimizing laundry loads, and managing refrigerator use to reduce energy consumption and appliance wear during summer heatwaves. 3 sources. https://clstr.news/cluster/energy-efficiency-tips-for-household-appliances-during-summer-heatwaves ### 2026-08-08: Home ventilation strategies during a heatwave To keep homes cool during a heatwave, open windows only when outdoor temperatures are lower than indoors, such as at night or in the early morning. 2 sources. https://clstr.news/cluster/home-ventilation-strategies-during-a-heatwave ### 2026-08-06: Dehumidify mode and shutter strategy cut indoor heat in summer Activating the AC’s dehumidify mode and closing shutters by day, then ventilating at night, can lower indoor temperatures by several degrees and improve comfort during summer heat. 3 sources. https://clstr.news/cluster/dehumidify-mode-and-shutter-strategy-cut-indoor-heat-in-summer ### 2026-07-28: Passive shading techniques help keep homes and terraces cool during heat waves Experts recommend timing shutters by orientation and using shade‑giving plants on terraces to reduce indoor and outdoor heat during heat waves, offering energy‑efficient alternatives to air‑conditioning. 3 sources. https://clstr.news/cluster/passive-shading-techniques-help-keep-homes-and-terraces-cool-during-heat-waves ### 2026-07-27: Phoenix and UK homes adopt window treatments to beat heat and sleep better Phoenix homeowners use window shades to cut heat, while UK residents combat soaring temps and sleepless nights with passive cooling tips and cost‑concern over air‑conditioning. 2 sources. https://clstr.news/cluster/phoenix-and-uk-homes-adopt-window-treatments-to-beat-heat-and-sleep-better ### 2026-07-20: US homeowners advised to customize thermostat settings amid heat wave Experts urge US homeowners to tailor thermostat settings during heat waves and adopt simple measures—blinds, fans, open doors—to cut cooling costs. 2 sources. https://clstr.news/cluster/us-homeowners-advised-to-customize-thermostat-settings-amid-heat-wave ### 2026-07-14: Homeowners advised to keep windows closed during peak summer heat Ventilate only in cool mornings/evenings, keep windows shut 11 a.m.–6 p.m., use curtains or reflective foil, and limit heat‑producing appliances to stay comfortable in summer heat. 16 sources. https://clstr.news/cluster/summer-2026-horoscope-highlights-for-cancer-libra-pisces-and-aquarius --- Cite as: Heat wave cooling, health, and energy efficiency guidance. CLSTR, https://clstr.news/situations/heat-wave-home-cooling-guidance