Update (0948ET): Several suppliers for Apple and Tesla announced the suspension of manufacturing operations in China on Sunday and Monday due to local electricity constraints. 

The latest is Pegatron, which assembles iPhones at manufacturing plants in Kunshan and Suzhou, announced Monday that it's "taking energy-saving measures to comply with local government policies," according to Bloomberg. 

Pegatron said Sunday that all operations were running normally, and it prepared alternative power generator sources should the government reduce or shut power to their plants.