Go yo the town nearest the data center, and tell everyone to use up as much power as possible. Than have a bot farm maximize the power draw of the servers by doing an almost DDoS attack. Keep the grid constantly under pressure so the UPSs in the data center can't compensate when the power goes out. Constant surges will destroy their equipment eventually, or just cause so many outages that people stop using the services.

This would cause people's appliances to shut down too, but if everyone turned off fridges and HVACs or whatever, and then just have heaters blow air outside constantly in high as much as possible, and maybe use ovens on broil at the same time, that might work.