The author repurposed an old iPhone 8 as a solar-powered OCR server, processing over 83,000 requests and 48GB of images using Apple's Vision framework. The setup uses a solar panel, power station, and mini PC, and has been running continuously for over a year. The author notes that the project has saved them around $84-120 CAD annually in electricity costs. The iPhone's battery health has held up reasonably well, with 76% capacity remaining after a year of continuous operation.