Under traditional net metering, customers are only billed for their net consumption over a billing cycle, meaning that any energy they consume from the utility can later be offset by energy production from their solar installation. As a result, even though a customer’s solar installation only makes power for them during the day, they can use excess energy production during the day to cancel out their nighttime usage and drop their electric bill down to nearly zero...
Changes to net metering policies fall into three general categories: 1) changes to how long excess generation credits can be carried forward and applied to future energy charges, 2) the application of fixed energy charges which cannot be offset with solar energy credits, and 3) changes to the value of electricity sold to the grid from a solar installation compared to the value of electricity bought from the grid.