Heat waves and innovation in air conditioning in the United States

This study investigates whether extreme heat episodes (heat waves) have contributed to the development of air conditioning (AC) technology in the United States. To this end, we use weather data to identify days at which heat and relative humidity were above levels comfortable to the human body, and match these with patent data at the county level for nearly a hundred years. We find that in the 2 years after a county has experienced extreme heat AC patents increase. Overall, average extreme heat exposure results in an increase of 7.5% greater innovation. We find no similar increase in the frequency of non-AC-related patent filings, and therefore conclude that heat waves result in innovation targeting their mitigation.