Modernizing the world’s electric grids is a critical enabler for achieving the societal benefits and avoiding brownouts or blackouts that come from optimizing the way we generate, distribute and use electricity. If implemented properly, distributed generation with advanced functionality and communications capability may even increase the reliability and stability of the grid.
UL continues to forge new paths on grid interconnection safety standards to keep pace with new power production applications, new product opportunities and new customer needs. We are also working closely with the state of California — the state at the forefront of incorporating distributed generation into its energy system — to draft UL 1741 SA (Supplement A) specifications for Grid Support Utility Interactive Inverters.
Advanced inverter testing is smart, reactive control of distributed generation (DG) for support of ongoing modernization of grids utilizing increasing levels of DG and renewable energy resources. Traditional utility interconnection requirements (IEEE 1547) require DG devices to disconnect when the grid is experiencing stability issues. The UL 1741 SA specifies the test methods needed to build the foundation for DG devices to stay online and adapt their output and overall behavior to stabilize the grid during abnormal operation rather than simply disconnecting.
The Rule 21 tariff is the inverter related revisions to the State of California Electric Tariff Rule 21 made by the California Public Utility Commission (CPUC). Rule 21 is a Source Requirement Document (SRD) to be used with the UL 1741 SA. SRDs set the specific parameter settings to be used with the test methods of the UL 1741 SA. Other SRDs may also be used with the UL 1741 SA as other markets look to build smart grid functionality into the modernization of their local area electrical power system.
The state of California has announced that inverters installed in the state will be required to comply with the Rule 21 tariff within one year of the publication (expected second half of 2016) of the UL 1741 SA. Other states are considering adopting similar installation requirements especially in areas containing high levels of DG and solar penetration. In this free webinar, find out what is involved, expected, and benefits of getting UL 1741 SA certification now to streamline your product access and be prepared for these new requirements.