Illinois

Illinois enacted S.B. 680 in August 2007, requiring investor-owned utilities in Illinois to begin offering net metering by April 1, 2008. In May 2008 the Illinois Commerce Commission (ICC) adopted final rules for net metering, effective May 15, 2008.  
 
In Illinois, net metering is available to electric customers that generate electricity using solar energy, wind energy, dedicated energy crops, anaerobic digestion of livestock or food processing waste, hydropower, and fuel cells and microturbines powered by renewable fuels. Systems up to 40 kilowatts (kW) in capacity that are intended primarily to offset the customer's own electrical requirements are eligible.* While Illinois's investor-owned utilities and alternative retail electricity suppliers must offer net metering, the state's municipal utilities and electric cooperatives are generally not required to do so.  
 
For residential customers, net metering is "typically" accomplished through use of a single, bi-directional meter. For nonresidential customers, net metering is "typically" accomplished through the use of a dual meter. Dual metering is required for nonresidential customers with systems greater than 40 kW but not greater than 2 MW. The utility must provide the necessary metering equipment for systems up to 40 kW in capacity, while customers with systems greater than 40 kW but less than 2 MW must pay for the costs of installing necessary metering equipment. (Net metering and dual metering are not available to systems greater than 2 MW.)  
 
For systems up to 40 kW in capacity, any net excess generation (NEG) during a billing period is carried over as a kilowatt-hour (kWh) credit to the following billing period. At the end of an annualized period, any remaining NEG credits in the customer's account expire. Customers may select an annualized period that ends with last day of either their April or October billing period for this purpose. All net-metering customers (and dual-metering customers) hold ownership and title to all renewable-energy credits (RECs) and greenhouse-gas credits associated with customer generation.  
 
For customers taking service under a time-of-use (TOU) tariff, any monthly consumption of electricity is calculated according to the terms of the contract or tariff to which the same customer would be assigned to or be eligible for if the customer was not a net-metering customer. When net-metering customers under TOU tariffs are net generators during any discrete TOU period, the net kWh produced are valued at the same price per kWh as the utility would charge for retail kWh sales during that same time of use period. Credits for NEG may be used to offset other charges assessed by the electricity provider.  
 
Each utility must provide net metering and dual metering until the load of its net-metering customers and dual-metering customers equals 1% of the total peak demand supplied by the utility during the previous year. The number of new eligible customers with generators that have a nameplate rating of 40 kW or less is limited to 200 total new billing accounts for Ameren Companies, ComEd and MidAmerican for the period of April 1, 2008, through March 31, 2009. Utilities are directed to establish an open enrollment period during the first month that net metering is offered. If applications during the open enrollment period exceed the limits described above, enrollment priority will be determined by lottery. Utilities may initially give preference to customers already enrolled in net billing or similar programs at their discretion. Subsequent applications will be addressed on a first-come, first-served basis.  
 
* Illinois allows dual metering for systems greater than 40 kW but not greater than two megawatts (MW), although the customer must pay for the metering equipment, and nonresidential customers must pay for "all taxes, fees and utility delivery charges" for the gross amount of electricity delivered by the utility. As an economic incentive, dual metering is generally less favorable to customers than net metering.