Washington, DC, U.S.A. --- (METERING.COM) --- May 25, 2012 - The number of electricity customers participating in net metering programs has increased sharply in recent years with an average annual growth of 56 percent between 2003 and 2010, including a 61 percent increase between 2009 and 2010.

However, still the electric customers with net metering represented only 0.1 percent of all customers in 2010, according to a release from the U.S. Energy Information Administration.

The EIA says that state policies and technological developments have led to the increase in residential and business consumers installing small scale, on-site generators. Starting around the late 1990s, many states began incentive programs to encourage the installation of renewable generation, including rebates, performance-based incentives, tax incentives, and low interest loans, as well as renewable portfolio standards. Tariffs standardizing aspects of net metering like compensation and interconnection rules are also an important part of this state-based effort.

In 2003, when the EIA began publishing data on the incidence of net metering, 127 utilities in 38 states and the District of Columbia reported having a total of 6,813 net metered customers. In 2010, 655 utilities in every state except for Tennessee reported net metered customers with the total number of customers increased to 155,841. Of these California accounted for 56 percent, followed by Colorado (6.3%), Arizona (5.5%), and New Jersey (4.8%).

The IEA also notes that while almost every state has a net metering policy, these policies vary in a number of ways. These include differences in technology and fuel types, capacity limits, aggregate capacity, size or type of power provider, and compensation.

In particular the wide range of capacity limits is a strong point of variation among states. New Jersey, for example, does not have a capacity limit, but instead has a requirement that the onsite energy production not exceed the customer's annual consumption.