We have been told the technologies of the intelligent grid are going to change the way we work and do business. It is going to transform the electro-mechanical power system of the last millennium into a 21st century digitally integrated power network. That is a pretty tall order when you think about it.

The electrical transmission grid isn't a national grid; actually, its three interconnection systems: the Eastern, Western and Electric Reliability Council of Texas (ERCOT) interconnections. The Eastern and Western interconnections are huge and asynchronous, which prevents direct interconnections between them. ERCOT is limited by regulatory reasons, which also prevent direct interconnections to the other systems.

This lack of connectivity is becoming an issue now that renewables (wind and solar) have entered the marketplace. We are caught up in a national quest to have 20% of electricity generated by wind by 2030. Independent power producers (IPPs) are encouraged to build facilities, but there is a problem. The locations rich in renewable resources are far removed from the load centers with little if any access to transmission facilities.

ERCOT has abundant wind-generation resources. So much so that there are times when more wind-generated electricity is available than there are buyers. At these times, the IPP gets pennies on the dollar for the power, which is not good for encouraging further development of wind power in this area. If it could be sold across interconnection boundaries, the IPP would receive a competitive price for its electricity, which in turn would support the continued expansion of wind power.

Many of the wind experts I interviewed for the “Renewable Energy” supplement (Transmission & Distribution World, March 2009) were frustrated by not being able to use wind efficiently because of these idiosyncrasies of the transmission system.

There isn't much interaction when the markets and the renewable resources are in different grids. Of course, there are interconnection points between the various grids, but they are few and far between. They are also power-transfer challenged. These interconnection points were developed using HVDC converters or variable-frequency transformers. Many are approaching 30 years in age.

Years ago I was involved with building an HVDC converter station and recently have been working on projects to extend the life of older HVDC facilities. Consequently, when I heard there was a proposal to build a three-grid interconnection project using HVDC and high-temperature superconducting (HTS) cable my interest level really jumped.

In October 2009, New Mexico's Gov. Bill Richardson, former energy secretary for the Clinton administration, held a news conference announcing the Tres Amigas Superstation (TASS) project. Gov. Richardson said when he was energy secretary he attended countless DOE meetings addressing the issue of connecting the three grids. He felt TASS offered a fresh approach to this problem. He went on to say that the New Mexico has leased TASS more than 14,000 acres (5666 hectares) near Clovis, New Mexico, and will support the project.

The Clovis area has been selected for the project because of its rather unique location — it's just a stone's throw from all three grids. Okay, a long stone's throw, but you understand what I mean. By locating in Clovis, there is less than 100 miles (185 km) between the three grids, and in terms of cross-country transmission, that is not far — in affect, a stone's throw.

During the news conference, Phillip Harris, CEO of Tres Amigas LLC and the former CEO of PJM Interconnection LLC, said, “TASS would be a merchant transmission hub for transferring green power between the three grids.”

Harris described TASS as a three-way-traffic roundabout-type of configuration using HVDC voltage-source converters to link the grids with American Superconductor HTS cable technology.

American Superconductor has invested about US$1.75 million in TASS and holds a position on the project's board of directors. In an Associated Press report, Russ Stidolph, CFO of Tres Amigas, said that financing for the development stage has been secured, which will take place in the next couple of years. There is no doubt that there is a lot of work yet to be done.

In The Wall Street Journal, FERC Chairman Jon Wellinghoff said, “This was a very interesting idea.” He went on to say FERC would look very closely at the TASS proposal. He felt FERC needed more of these creative approaches to encourage renewable energy development.

This project is still in its initial stage and faces many regulatory challenges. It is not a slam-dunk technology-wise either. VSC technology hasn't been used in applications much above 300 MW, although there are proposals in the 500-MW range. HTS cable's longest installation has only been about 2000 ft (0.6 km) so far.

It is intriguing. It could unravel, but support continues to grow. Every advancement we make has to deal with issues such as these, but as Wellinghoff pointed out, it is a creative approach and we need more of them. That is the heart of the intelligent gird — using technology to solve old problems.