Net Metering

Earlier this year, Net Metering for small (2,000 kW and below) renewable (solar PV, wind etc.) electricity generating sources was legislated and put in place by the utilities.

In Ameren, the rules are generally as follows:

A flat rate customer with an electricity generator will get billed for the amount of electricity their household used minus the amount it produced. If they generated more power than they used then they will receive a credit in their account for future bills. Your account will keep the credits from month to month until they are used up, or if you reach the end of the year (defined as April-April or October-October).

Customers with hourly prices (such as Power Smart Pricing customers) are billed under a similar standard. The difference is that each hour is used as either a credit or a charge based on the rate for electricity that particular hour. These hourly energy charges and credits get added up over the month and result in either a net dollar amount energy charge or dollar energy credit for that month. Any leftover credit will be used on other parts of that bill (taxes, monthly customer charge, etc). If there is still a dollar amount credit left, it rolls over to the next month's bill. By the end of the year any leftover credit is forfeited.

Here is a handy device that will help your household keep track of the performance of your solar PV system: