The size of your Sunscription is based on your annual historical energy use. This means that if you use more electricity, you will have a larger subscription, and if you use less electricity, you will have a smaller subscription. Most subscribers have a Sunscription sized between 80-105% of their annual historical energy use, depending on the program and state guidelines.

If you are a ComEd electricity customer and have excess Sunscription credits - or a credit amount that is greater than your total charges with ComEd – the credits will rollover and apply to charges in future months. ComEd Sunscribers are initially sized at 90% of their historical energy usage to limit the accumulation of excess credits. Excess credits rollover indefinitely until they are either used up or until the customer leaves ComEd service territory, at which point any excess credit would expire.

If you are an Ameren electricity customer and have excess Sunscription credits - or a credit amount that is greater than your total charges with Ameren – the credits will rollover and apply to charges in future months. Excess credits rollover each month until April, at which point, any remaining excess credit expires. Because solar energy production – and therefore bill credits – are lower in the winter and early spring, it is expected that very few if any Sunscriptions sized at 85% of a resident’s historical energy use would result in excess credits in the spring. Subscribers whose Sunscriptions do produce excess credits most commonly do so in the summer when there is a high amount of energy production at the Solar Garden.
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