Transmission and distribution networks are becoming smarter and stronger to provide the real time flexibility to handle the new challenges which include increasing levels of variable renewable and distributed generation, changing demand patterns and increasing deployment of energy efficient technologies.
These challenges vary from one country to another, resulting in the use of different solutions to meet them and different maturity levels in the implementation of those solutions.
As part of a process to survey and analyze achievements in the application of different smart grid approaches, the International Smart Grid Action Network (ISGAN) has compiled a T&D Case Book reviewing projects from seven countries. The aim is to share experiences, highlighting a wide range of applications and lessons learned.
Synchrophasors improve reliability
In the United States, synchrophasors increase power transmission in existing transmission infrastructure, allowing the introduction of more renewable energy and increasing the reliability of electricity delivery.
In Italy, WAMS (wide-area measurement systems) technology has improved the operation of the transmission system by better tracking of system stress and dynamic phenomena that potentially could lead to system disturbances.
HVDC-VSC technology increases security of supply
In Sweden, HVDC advanced voltage source converter (HVDC-VSC) technology increases transmission capacity and helps avoid voltage collapse in the grid. AC and DC overhead and underground cables are combined to upgrade the capacity in existing transmission corridors to minimize the environmental impacts.
In Ireland, HVDC-VSC technology is used to build a combined submarine and underground interconnector linking two electricity markets and thereby decreasing electricity prices and increasing security of supply. The project provides a good illustration of community involvement, simultaneously increasing the acceptance of the project and youth interest in engineering.
Smart solutions increase capacity
In Austria, smart solutions in the distribution grid increase the hosting capacity for distributed energy resources, including renewable electricity production, other types of distributed generation, demand response and electric vehicles. The case illustrates that greater capacity can be created without adding primary infrastructure.
In South Africa, a new visualization system reduces down time and improves operation, maintenance planning and fault location.
Smart substations improve operations
In France, smart substations demonstrate how electrical equipment could safely operate closer to physical limits, thereby minimizing attendant investments in equipment improvements. At the same time, functionality has increased with enhanced monitoring and diagnostics. New sensor technologies improve operation and maintenance of equipment.
TOU tariffs increase customer involvement
In Italy, time-based (TOU) tariff systems increase customer involvement and improve the efficiency of the system by balancing peak and off-peak consumption to better fit with the availability of power. Several proposed applications may further improve the systems.