Setting your thermostat lower in the summer will not result in the air conditioning system using extra electricity continuously. However, it might require the AC to run longer initially to reach the lower temperature you've set. Once the desired temperature is achieved, the AC will work to maintain that temperature, consuming energy at a rate based on the heat gain of your home and the outdoor temperature.
The energy consumption of an air conditioning system is determined by the temperature difference between the indoors and outdoors. The greater the difference, the more heat will flow into your home from the warmer outside environment, requiring the AC to work harder to maintain the lower temperature.
Here's a simple example to illustrate the concept:
Scenario A: You set the thermostat to 75°F (24°C) when it's already 75°F (24°C) outside.
- The AC will not need to run as there is no temperature difference to overcome.
Scenario B: You set the thermostat to 70°F (21°C) when it's 95°F (35°C) outside.
- The AC will have to work harder and longer initially to cool the indoor temperature from 95°F (35°C) to 70°F (21°C).
- Once the desired temperature is reached, the AC will cycle on and off to maintain the set temperature. The rate of cycling will depend on factors like insulation, home heat gain, and outdoor temperature.
Therefore, the constant requirement of extra electricity only occurs if there is a continuous difference between the indoor and outdoor temperatures due to the thermostat being set lower than the outdoor temperature. Once the indoor temperature stabilizes at the set point, the electricity consumption will decrease significantly as the AC operates in shorter cycles to maintain that temperature.