You can estimate the memory requirements of a pipeline you want to load beforehand with [this Space](https://huggingface.co/spaces/diffusers/compute-pipeline-size/).
To load a diffusion pipeline locally, use [`git-lfs`](https://git-lfs.github.com/) to manually download the checkpoint (in this case, [`runwayml/stable-diffusion-v1-5`](https://huggingface.co/runwayml/stable-diffusion-v1-5)) to your local disk. This creates a local folder, `./stable-diffusion-v1-5`, on your disk: