Heat olive oil in a soup pot over medium-low heat and saute onion, stirring occasionally, until soft, about 5 minutes. Add butternut squash and carrots; cook and stir for a few minutes. Do not let the onions brown.
Add water, vegetable bouillon, ginger, and orange zest to the pot. Increase heat to medium and slowly bring to a simmer. Cover and cook until carrots soften, about 20 minutes.
Remove orange zest strips and discard. Blend soup into a smooth puree using an immersion blender. Season with salt and pepper.