boincAutoDischarger

Use BOINC to artificially increase the number of battery cycles in your Mac.

Installation requirements

• BOINC (of course);
• boinccmd (the CLI manager for BOINC), make sure that is is in your PATH;
• Python3 (brew install python3);
• terminal-notifier, for notifications;
• iStats (optional), for integrated nice stats.

Usage

• ./autodischarger.py runs with a default refresh timeout of 10 seconds and no iStats;
• ./autodischarger.py [timeout] stats runs with a refresh timeout of [timeout] seconds and iStats.

Why?

My university provides all students with Macbooks with a free of charge (other than the tuition fee) lease. Since if you have AppleCare you are entitled to a free battery replacement when your it reaches 80% of the original factory capacity, I have created this tool to moderately degrade the battery on my Mac in order to get a free replacement just about when the AppleCare coverage will end.

If you have AppleCare and for some reason you too want to get a "free" battery, this is the tool for you.

What

This is a ~200 line Python 3 script that uses boinccmd in order to change automatically the settings of BOINC in order to maximize resource usage (and thus battery consumption) while your Mac is using battery power. BOINC will run with a 80% CPU limit when your Macbook is on battery power with at least a 20% charge. Once the charge runs out, BOINC will slow down to 10% CPU usage and the script will send a notification telling you to plug the charger. Once you are charging, the script will start waiting for the battery to be at least 90% charged, and then will prompt you to disconnect the charger and the cycle will start again.

My setup uses a power strip to turn the charger manually on and off. I think the process can be entirely automated by using a smartplug and automating its activation from this script (e.g the TP-LINK HS100 has this open source python control library), but unfortunately I am currently not able to buy such a product both in a physical store or online and therefore I am tediously switching on and off the charger myself every hour (I know)

This is not a finished product

Please feel free the hardcoded constant values for the charging thresholds and various BOINC config files. I have created this script for personal use and I am just sharing it here for someone that is curious enough to hack it to their needs.

Another quick note: my AppleCare expiration date is hardcoded as well, feel free to change that.

I might be able polish this script in the following days, but I have a quite busy class schedule (albeit remote). So, if you want, just create a pull request to tidy up this mess and I will accept it.

Use at your own risk

I am not responsible if your Mac will be damaged in any way by using this script. Please be careful since this is a fairly resource intensive setup and Macbooks are not exactly known for their amazing cooling system. Use at your own risk