Air Conditioner Temperature Regulation in India

The Union Ministry of Power is considering a proposal to restrict the temperature range of new air conditioners (ACs) in India to between 20 degrees and 28 degrees Celsius. This potential restriction would apply to ACs used in households, hotels, and cars. Although no firm decision has been made yet, the Ministry is exploring this option to enhance energy efficiency and public health.

Background and Previous Initiatives

• In 2018 and 2021, the Ministry, under R.K. Singh, engaged with AC manufacturers to set an optimal temperature setting from an energy efficiency and health perspective.
• The Ministry considered fixing the default temperature setting at 24 degrees Celsius, following a public awareness campaign and consultations.

Energy Efficiency and Benefits

• Increasing the AC temperature setting by 1 degree Celsius can save 6% of electricity consumption, according to R.K. Singh.
• The Bureau of Energy Efficiency (BEE) projected that setting ACs at 24 degrees Celsius could save 20 billion units of electricity per year.
• By 2030, the total connected load due to ACs is expected to reach 200 gigawatts.

Health Implications of Low Temperatures

• Temperatures below 18 degrees Celsius are considered uncomfortable and unhealthy, as they can increase blood pressure and risk of hypertension.
• Studies involving children in Japan, New Zealand, and the UK found that AC settings above 18 degrees Celsius improved breathing during sleep.
• Whole-house warming with insulation or heaters can reduce respiratory infections and lower antibiotic usage.

Global Context and Usage

• The International Energy Agency estimated 2 billion ACs worldwide in 2018, with 1.5 billion residential units as of 2022.
• 43% of people in the Asia Pacific region needed additional cooling as of 2022.

AC Functionality and Efficiency

• ACs function by moving heat from one space to another using a refrigerant in a vapour-compression cycle.
• Efficiency is highest within a specific temperature range for refrigerant heat transfer, decreasing outside this range.

Health Studies and Recommendations

• Comfort is defined by maintaining a body's core and mean skin temperature constant, without sweating or shivering.
• ASHRAE-55 and ISO 7730 standards base comfort on factors like clothing and cultural sensibilities.
• WHO's 2018 guidelines recommend 18 degrees Celsius as the minimum safe living-room temperature in cooler climates.

Studies on Low Temperature Impact

• A 2014 study linked indoor temperatures under 18 degrees Celsius to a 9% risk of hypertension.
• The English Longitudinal Study of Ageing found higher cholesterol and weaker grip strength in colder homes.
• A UK study in 2022 associated cold homes with increased depression and anxiety risks.

Considerations for India

• Most studies have focused on temperate countries, with limited research in tropical or subtropical regions.
• People exposed to cold may also face damp surfaces and energy poverty, worsening health outcomes.

The potential regulation of AC temperature settings aims to achieve energy savings and public health benefits, addressing both environmental and health concerns.