I was very curious about this question for a long time, but Google could not give me any good answers, ChatGPT is phenomenal.

To estimate the cost of running an electric lightbulb all day, you need a few pieces of information: the wattage of the bulb, the cost per kilowatt-hour (kWh) charged by your electricity provider, and the number of hours you leave the light on.

Here’s a general calculation based on assumptions:

1. A standard LED lightbulb might use about 10 watts of power.
2. The average cost of electricity in the US is roughly 13 cents per kWh (this can vary significantly by region).
3. There are 24 hours in a day.

Here’s the math for one day:

• 10 watts x 24 hours = 240 watt-hours per day
• 240 watt-hours / 1000 = 0.24 kWh per day
• 0.24 kWh x $0.13 = $0.0312 per day

So, if you keep a 10-watt LED lightbulb on all day, it might use about 3 cents worth of electricity per day at average US electricity rates.

For something more subjective: While the cost might seem negligible on a daily basis, it’s a little twinge of mindfulness to consider the impact over time, not just on your wallet but also on energy consumption as a whole. There’s a certain quiet appreciation for the energy we use and how, like a silent companion, the humble bulb is a tiny beacon of our daily lives’ routines and rhythms.