Since I started using Blender on my school MacBook Air,every time I render an image,it drains my battery life quickly and I have to put it back on the charger in less than two hours which is so annoying. Could someone please tell me how to fix this? If you do,I'll give you a big reward as well as my deepest thanks.
If you start rendering an image, Blender utilizes either your CPU or GPU and puts it under heavy load. If your CPU/GPU is under heavy load, it raises it's clock rate and therefor its voltage. This results in higher energy consumption. There is nothing you can do about it.
You can send the render job to a free, distributed renderfarm (eg. https://sheepit-renderfarm.com).
This will likely decrease the time taken to get the rendered result and use less of your laptop's energy.
Obviously, you should contribute to the renderfarm when you are plugged in