A simple, free online tool for understanding home power usage and costs

I used the OpenAI Codex app to develop an idea I had while talking with my wife about power companies raising their prices during periods of high demand. We recently paid up to 90¢ per kW/h, which is insane, but when the kids hear “90¢,” they think it’s nothing. They don’t understand power pricing—or even what a kilowatt-hour is. https://kilowhat.jiovanie.com/ In about 15 minutes, I had a fully working web app that approximates how much power devices in your home use and how those costs add up over a month. You can see the cost of a single device or set up all the devices in your home, specify how long each one runs per day, and build a full monthly tally of power usage. The app also shows how a “small” 20¢ increase in the price per kW/h can add up to a massive bill at the end of the month. I designed it to be completely free to use, with no accounts or login required, no personal information collected, and zero tracking. My initial prompt was: ```text "I want to create an interesting, interactive, and maybe even FUN app that explains what kilowatthours are and how a small change in the price of a kW/h can have a huge effect on your monthly power bill. I want to make this tool available for free to anyone so it needs to work across devices and OSs and even form factors. I want it to be fun to use so it should have lots of style and flair and be very interactive. a price slider and device selector will enable people to see how much their devices draw power and how much it costs to use." ``` After the initial creation, I discussed the changes and tweaks I wanted, asked Codex to create a logo, and decided on a visual style. Then I provided my web-hosting information so it could upload the app and make it accessible to anyone. 1. I described my idea about rising power prices and the need to explain kilowatt-hours and monthly costs. 2. I asked OpenAI Codex to create an interactive app with a price slider and device selector that would work across devices, operating systems, and form factors. 3. I discussed changes and tweaks, asked it to create a logo, and decided on the app’s visual style. 4. I provided my web-hosting information so Codex could upload the app and make it publicly accessible.