How it works
Any Internet-connected device that controls flexible electricity demand can harness load shifting: smart thermostats, heat pumps, EVs and EV charging infrastructure, battery energy storage systems, building energy management software, even laptop computers, cell phones, and refrigerators.
Shifting load to the right times can reduce emissions. WattTime was founded to answer the question, “watt” times do reduce emissions? We research and help raise awareness of techniques to answer that question, using what’s known as marginal emissions data. We also share these data via an API so device companies can know what times will reduce the most emissions. Today, device makers and software providers are using WattTime’s data to automatically time over 900 million devices to reduce emissions via AER.
AER can be designed to reduce as much emissions as possible without getting in the way of other goals, like cost and convenience. There’s no need for end users to ever have to feel a difference in how cool their home is. Their EVs are charged and ready to drive when they’re ready to go. But behind the scenes, they’ve seamlessly and automatically cut their emissions with the proverbial push of a button.
Normal vs. Emissions-Optimized EV Smart Charging: The power grid's marginal emissions rate (dark line) varies overnight, while an EV is plugged in. Normal "whenever" charging starts right away, blind to the grid's emissions intensity at that time (grey area). AER-enabled charging waits until grid electricity is cleaner, preferentially choosing lower-emissions times (yellow area) while still recharging the battery by the end of the charge window (light blue area).