Reliability and Resiliency



At VEC, we take reliability and resiliency seriously to minimize outages and to make sure we have a robust system to withstand weather and other events. VEC recognizes that the safe and reliable operation of the grid is important both to deliver energy to our members and to provide a reliable interconnection for distributed generation projects. VEC has been an innovator when it comes to the implementation of smart grid technology. VEC’s Control Center is staffed around-the-clock, seven days a week by qualified System Operators. VEC uses a variety of tools to decrease outages and to ensure VEC is providing safe and reliable power


Reliability includes system performance during normal operations and the mitigation of  outages from trees, weather, car pole crashes, etc.  Reliability metrics are reported annually to Vermont’s Public Utility Commission.  Reliability activities include:

  • Vegetation Management
  • Utilizing coated conductor
  • Replacing older and smaller conductor
  • Snow unloading mitigation
  • Voltage stability
  • Sectionalizing (e.g., installing fuses on side taps)

Resiliency is how quickly a utility recovers from a major event. The impact of resilience investments may not be realized until after a major outage event. Resiliency activities include:

  • Moving wire from Rights-of-Way to road side to make restoration faster
  • Sectionalizing (e.g., reclosers, switches, etc.)
  • Tie lines and back-up circuits
  • Interconnected substations and circuits

VEC’s Reliability and Resiliency Plan outlines our strategy for “Keeping the Lights On” and “Getting the Lights Back On Faster”.

Annual Reliability Report

VEC is required to file an annual 4.900 report, which contains a detailed assessment of annual outage performance as well as a plan for how to improve reliability to its members. VEC’s Service Quality and Reliability Plan (SQRP) identifies requirements for VEC’s System Average Interruption Frequency Index (SAIFI) and Customer Average Interruption Duration Index (CAIDI).  

SCADA

Supervisory Control and Data Acquisition (SCADA) enables VEC to view real time data as to the status of equipment and other assets (open vs. closed for instance) as well as their analog values (power, voltage, current, etc.). It also allows us to remotely operate assets such as reclosers and switches.  Learn more.

Outage Management System (OMS)

VEC has used an Outage Management System (OMS) supplied by the National Information Solutions Cooperative (NISC) since February 2008.  The system relies on four inputs:

  • AMI meter information provided by Aclara.
  • Integrated Voice Response (IVR) automated phone system data.
  • Member service inputs from the VEC Member Service Department.
  • Inputs from VEC’s external overflow call center.

AMI Metering Systems

VEC has been operating its present AMI system since 2005. It relies on Powerline Carrier (PLC) communication to provide two-way communications between the substations and meters. Data backhaul from the substation to the Johnson Headquarters is provided using mostly fiber optic cable. The system is extremely reliable and on average provides 99.7% read performance.

Vermont Weather Analytics

The Vermont Weather Analytics Center (VTWAC) is a powerful tool that enables utilities to better protect communities, meet customer needs, and garner renewable energy’s full value. VTWAC delivers advance weather forecasts up to three days ahead, precise to 1 km², linked to customer demand data and to solar and wind generation models. Partners in this work included every local Vermont utility, state agencies, renewable energy developers, Vermont academic institutions and the formidable intellectual resources of IBM Research. The results are the most precise and accurate wind and solar generation forecasts in the world.

As the penetration of renewables increases, there is a need for accurate monitoring of generation output, load forecasts and generation forecasts. VEC has taken an active role in the Vermont Weather Analytics Center. The joint effort between Vermont Distribution Utilities, VELCO, and IBM is to increase grid reliability, lower weather-related operational costs and optimize the use of renewable generation resources.

The Center uses four models:

  1. Deep Thunder which will produce accurate weather forecasts up to 48 hours in advance down to 2 sq km,
  2. Demand Forecast Model which will increase the accuracy of state load forecasts,
  3. Renewable Forecast Model which will produce generation forecasts for solar and wind farms, and
  4. Renewable Integration Stochastic Engine which will integrate the results of the aforementioned models to optimize the value of Vermont's generation, demand response, and transmission assets.

Drone Technology

VEC always looks to leverage technology to improve the efficiency and safety of our operations.  Drones offer a range of capabilities that enable us to enhance and benefit our operations in a number of ways.  Learn more here.