Today, the U.S. is served by three large electric grids:
- the Eastern Interconnection
- the Western Interconnection, and
- the Texas Interconnection (also known as ERCOT, or Electric Reliability Council of Texas)
Because the grids operate independently, electric power produced in the West cannot be delivered to a customer in the East.
Isolated grids prevent our nation from tapping the full potential of renewable energy resources. For example, electricity customers located in Virginia cannot get energy produced by photovoltaic panels in the sun-drenched Nevada desert. Customers living in Seattle can't use electricity created by wind farms on the Texas plains.
A project underway in the Southwest is set to fix all that.
The Tres Amigas SuperStation - planned for 22.5 square miles in Clovis, New Mexico, near the Texas border - is expected to hook all three grids together by 2014.
The SuperStation will serve as a balancing authority, enabling a reliable and efficient flow of power from multiple integrated resources and allowing participants from multiple grids to buy, sell, and deliver electricity to each other. The SuperStation is also expected to expand the marketplace for sustainable energy and spur its development. Wind resources in New Mexico alone could provide more than 54,700 additional megawatts.
Some technical features of Tres Amigas SuperStation are:
- Three HVDC (high voltage DC) terminals each receive alternating current (AC) from one of the three grids.
- Incoming AC power is converted into direct current (DC) suitable to travel along a ring of 5-gigawatt HVDC (high voltage DC) superconductor cables.
- The superconductor cables are buried underground to reduce the risk of weather-related outages, vandalism, and terror attacks.
- Energy gets converted back to AC before it gets sent out into one of the linking grids.
- On-site energy storage batteries give added flexibility to handle intermittent supply from renewable energy sources.
- Tres Amigas plans to purchase renewable energy to power the SuperStation.
The superconductor cables will be provided by American Superconductor Corporation. Construction of the Tres Amigas SuperStation is due to begin in 2012, and will be overseen by CH2M Hill.