Practice carbon aware development.
Hard to implement
8 High impact score
The current carbon intensity of the electricity grid drives the decision as to when energy intensive processes (such as deployments, data transfers, file uploads/downloads) should be run.
Therefore, do more when renewable energy is flooding the grid, do less when fossil fuels are.
Tools such as ElectricityMap highlight grid intensity. Open Source projects such as the Carbon Aware SDK are written specifically for aiding carbon aware development.
N.B. this could be a server-side batch job (for example) or front-end adaptations.