In order to fully integrate wind and other dispersed sources of energy into the system, America’s patchwork transmission networks need to be more closely interconnected and synchronized. An...
The most economical energy savings might be found in grid efficiency.
utilities for both peak reduction and energy savings during non-peak periods.
The results of the Distribution Efficiency Initiative Study validated by EPRI’s Green Circuits distribution project indicate 1- to 3-percent energy savings, a 2- to 5-percent demand reduction, and a 5- to 10-percent VAR reduction can be achieved through voltage optimization. Assuming an adoption rate in the range of 25 to 50 percent of residential distribution substations, voltage optimization could achieve an approximate annual savings range of 4 million to 28 million MWh by 2030. Voltage optimization can be fine-tuned further with the deployment of smart-grid systems using the data from advanced metering infrastructure (AMI) systems to measure and determine the minimum service voltages, eliminating assumptions and potentially producing an additional 1- to 2-percent energy savings.
Moving Beyond Distribution
During 2009, a series of domestic and international workshops were held to discuss the state of transmission efficiency and options for improvements. The workshops brought together stakeholders in the industry including about 320 participants from transmission owners and independent operators, vertically integrated utilities, the vendor community, trade organizations such as the Edison Electric Institute (EEI), and regulatory bodies such as the Federal Energy Regulatory Commission (FERC) and North American Electric Reliability Corporation (NERC), various state public utility commissions, and members of academia, research organizations and the media.
Transmission presently is operated to first meet reliability standards and second to meet market needs. As such, loss reduction is typically one of the functions for optimization. However, as a result of the series of workshops and in conjunction with an executive council, EPRI is developing a framework to include efficiency in the operational strategies of transmission owners, independent system operators and fully integrated utilities. This framework is based on the following principles:
• Efficiency is more than simply reducing losses: An efficient system is low in losses, but it also increases utilization of existing transmission assets and enables smarter integration of renewable and storage technologies.
• Efficiency initiatives require that reliability remains a primary focus: There are technologies and practices available that increase the efficiency of the transmission system while maintaining or enhancing reliability.
• Efficient transmission will be built on the shoulders of new and upgraded systems: More transmission is essential for enabling renewable resource integration, improving reliability and achieving optimum efficiency. Sensors, communications, and using data to achieve greater control are key enablers for achieving and improving efficiency.
• Efficiency must be included in future business cases: Proposed transmission improvement projects for capacity and voltage stability improvements—as well as transmission improvements to connect to such clean and innovative energy technologies as renewable resources and storage—must include efficiency considerations as part of a comprehensive energy delivery resource plan.
• A regulatory framework with incentives can lead to efficiency improvements: To incentivize transmission efficiency, revisions to the regulatory framework might be required.
From Workshops to Actions
Using this framework, EPRI will facilitate information and experience sharing for evaluating methods and strategies for improving efficiency and reducing transmission losses. It’s the foundation for an emerging demonstration initiative focused on transmission efficiency and provides for a consistent