In December 2003, the Nevada Public Utilities Commission (PUC) adopted interconnection standards for customers of NV Energy (formerly Nevada Power and Sierra Pacific Power) with on-site generation up to 20 megawatts (MW) in capacity. These standards are largely consistent with IEEE 1547 standards, California's interconnection rule (California Rule 21) and the model interconnection agreement developed by the National Association of Regulatory Utility Commissioners (NARUC). Significantly, the PUC determined that NV Energy may assess customer-generators for past fuel and purchased-power expenses in tariffs. NV Energy has incorporated the standards into their tariffs as [http://www.nvenergy.com/company/rates/snv/rules/images/Rule_15_South.pdf Rule 15].
The interconnection standards approved by the PUC also updated Nevada's net-metering policy, originally enacted in 1997. Previously, Nevada Revised Statute 704.774 addressed basic interconnection requirements for net-metered renewable-energy systems with a maximum capacity of 10 kilowatts. This statute requires net-metered systems to meet standards established by the Institute of Electrical and Electronic Engineers (IEEE), the National Electrical Code (NEC), and Underwriters Laboratories (UL). Customers who complied with these guidelines could not be required to install additional equipment (such as a manual external disconnect switch), abide by additional safety requirements or purchase additional liability insurance. An October 2008 PUC order further clarified the issue of liability by specifically requiring the removal of any tariffs' obligation that the utility be named as an additional insured on the customer's insurance.