Consolidated Edison’s (Con Edison) has produced benefits from installing voltage control equipment on portions of its 4kV feeders and substations.
Since 2009, the U.S. Department of Energy (DOE) and the electricity industry have jointly invested over $7.9 billion in 99 cost-shared Smart Grid Investment Grant (SGIG) projects. Consolidated Edison’s (Con Edison) SGIG project has produced benefits from installing voltage control equipment on portions of its 4kV feeders and substations. Initial benefits include an increase in 4kV substation capabilities by 31.1 megavolt-amperes (MVA), or 2.8% under peak load conditions, with net savings of $15.7million, reductions of reactive power requirements at the aggregate level of 33 substations in Queens by 12.3% and 9.9% over a one-year test period, and reductions in annual system energy losses by 4,500 megawatt-hours (MWh) that saved an estimated $0.34 million in annual energy costs and reduced CO2 emissions by about 340 metric tons.
Con Edison has deferred costly capacity upgrades due to improvements in voltage controls and power factor corrections, which have reduced needs for electricity supplies. When operated properly the automated capacitors can produce near-unity power factor ratings, and thereby released capacity that distribution system planners and operators can use to defer capacity upgrades, manage capital expenditures, improve operating flexibility, and increase reliability. Using LTC controls to moderate the effects of circulating reactive flows have reduced de-ratings, extended the life of the transformers, and improved reliability through lower likelihood of equipment failures.
Efforts to apply automated controls for voltage and reactive power management on 4kV distribution systems are part of a broader Con Edison strategy to apply smart grid technologies on both the utility and customer sides of the meter to save energy and improve the reliability, efficiency, and affordability of electricity. Con Edison is showing that a more comprehensive set of tools are created for grid planners and operators when demand-side solutions like demand response and end-use efficiency are integrated with automated controls for voltage and reactive power management. Looking ahead, Con Edison plans to apply these techniques where appropriate to additional portions of their service area.