The Power to Choose Clean Energy

You’re looking at the real-time cleanliness of a local electric grid for ZIP CODE =

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Green Index

WattTime Green Index


The WattTime Green Index ranges from 0 to 100; the higher the number, the dirtier the grid.


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WattTime combines a variety of inputs and conducts a calculation to produce a single number representing the relative cleanliness of the grid.

The WattTime Green Index refreshes every 5-minutes and is plotted on the graph above to provide decision-making insight for energy consumption. As you can see, the marginal fuel on the grid varies wildly and there are times that are cleaner than others, giving us all a choice in the type of electricity we want to use.