By Ashleigh Cotting

Scheduled capacity additions in the Electric Reliability Council of Texas Inc. region in 2016 are expected to total nearly 12,500 MW, with wind capacity accounting for approximately 63%. As of a late February analysis, the region also had 23 MW of capacity scheduled to retire.

At the end of 2015, ERCOT's operating capacity totaled 101,553 MW. Gas-fired facilities, at 59,507 MW, totaled nearly 59% of operating capacity, followed by coal-fired capacity, at just over 19,000 MW, or nearly 19%, and wind, at just over 16,200 MW.

If new capacity comes online as projected, the ERCOT region will have a total operating capacity of just over 113,000 MW at year-end 2016. Gas will still be the dominant fuel type, at almost 62,000 MW. However, the fuel's overall share of operating capacity will drop to 55% as other new technologies are used.

Another roughly 8,000 MW of wind capacity is expected to come online in 2016, bringing the resource's total in ERCOT to about 24,000 MW, or 21% of the region's fuel mix. Some specific projects are going to be located outside of ERCOT's geographic region but are still considered part of ERCOT's resource mix because their output will be delivered into the ERCOT market. About 2,000 MW of new solar capacity is expected to become available this year as well, a nearly 10-fold increase over the amount of solar operating in 2015.

For a number of reasons, renewables are a popular new power generation resource in ERCOT. The state has strong winds. According to the U.S. Department of Energy, locations with an annual average wind speed of 6.5 meters per second or higher at a height of 80 meters are generally considered suitable for utility-scale wind development. The majority of the state of Texas sees annual average wind speeds of 6.0 meters per second or higher, making much of the state ideal for wind capacity installations. In mid-February, ERCOT logged a record peak of 14,023 MW of wind serving the region.

Texas also has a variety of state-level incentives, such as rebate programs and tax credits, which encourage utilities to install wind and solar capacity. These, when combined with the recent extension of federal tax credits for renewable energy and the state's renewable portfolio standard, create a favorable environment for renewable energy development. State policy, under the Competitive Renewable Energy Zone, or CREZ, initiative, has led to the construction of numerous miles of high-voltage transmission lines to move wind-generated power to consumers.

Although most of the new capacity expected to come online in ERCOT this year is wind, four of the five largest projects by planned capacity are gas-fired. The largest of these projects is Golden Spread Electric Cooperative's Antelope-Elk Energy Center. The overall facility will total 808 MW when completed. The first 202-MW phase began operation last year and phase 2, totaling 404 MW, is currently under construction, with completion expected in April. The final 202-MW phase, currently considered in early development, is expected to be completed later this year. The plant site is in Hale County, Texas.

The largest wind energy facility expected to begin operation in the region in 2016 is private developer Torrecillas Wind Energy LLC's 400-MW Torrecillas Wind project in Webb County, Texas.

The "under construction" status is assigned to a project when a company has broken ground and does not include site preparation. This includes activities such as pouring the foundations for building structures and erecting framework. A project's likelihood of coming to completion increases when it moves on to the late stages of development.

As of Feb. 24, only a small amount of generating capacity, 23 MW, was scheduled to retire during 2016. The largest scheduled retirement is the 18-MW Silas Ray ST, which began operating in the early 1950s and is owned by the Brownsville Public Utilities Board. The natural gas-fired plant is located in Cameron County, Texas. The University of Texas at San Antonio also plans to retire two units: a 3-MW gas-fired facility of the same name and the 2-MW oil-fired UTSA TEP II, both located in Bexar County, Texas.