Item 2. PROPERTIES

The following description excludes three power plants (Monticello, Big Brown and Sandow) with a total installed nameplate generation capacity of approximately 4,167 MW that were retired in the first quarter of 2018.

Luminant's generation fleet consists of 49 power generation units, all of which are wholly owned and operate within the ERCOT electricity market, with the location, fuel types, dispatch characteristics and total installed nameplate generation capacity for each generation facility shown in the table below:

Our wholesale commodity risk management business also procures renewable energy credits from wind generation to support our electricity sales to wholesale and retail customers to satisfy the increasing demand for renewable resources from such customers. As of December 31, 2017, Vistra Energy had long-term power purchase agreements to annually procure approximately 400 MW of renewable energy. These renewable generation sources deliver electricity when conditions make them available, and, when on-line, they generally compete with baseload units. Because they cannot be relied upon to meet demand continuously due to their dependence on weather and time of day, these generation sources are categorized as non-dispatchable and create the need for intermediate/load-following resources to respond to changes in their output.

Fuel Supply

Nuclear — We operate two nuclear generation units at the Comanche Peak plant site, each of which is designed for a capacity of 1,150 MW. Comanche Peak Unit 1 and Unit 2 went into commercial operation in 1990 and 1993, respectively, and are generally operated at full capacity. Refueling (nuclear fuel assembly replacement) outages for each unit are scheduled to occur every eighteen months during the spring or fall off-peak demand periods. Every three years, the refueling cycle results in the refueling of both units during the same year, the latest of which occurred during 2017. While one unit is undergoing a refueling outage, the remaining unit is intended to operate at full capacity. During a refueling outage, other maintenance, modification and testing activities are completed that cannot be accomplished when the unit is in operation. Over the last three years the refueling outage period per unit has ranged from 30 to 40 days. The Comanche Peak facility operated at a capacity factor of 84%, 101% and 99% in 2017, 2016 and 2015, respectively. The capacity factor for the year ended December 31, 2017 reflected an unplanned outage at one of the units between June and August 2017.

We have contracts in place for all our nuclear fuel requirements for 2018. We have contracts in place for the majority of our nuclear fuel requirements through 2019. We do not anticipate any significant difficulties in acquiring uranium and contracting for associated conversion, enrichment and fabrication services in the foreseeable future.

The nuclear industry has developed ways to store used nuclear fuel on site at nuclear generation facilities, primarily through the use of dry cask storage, since there are no facilities for reprocessing or disposal of used nuclear fuel currently in operation in the U.S. Luminant stores its used nuclear fuel on-site in storage pools or dry cask storage facilities and believes its on-site used nuclear fuel storage capability is sufficient for the foreseeable future.

Coal/Lignite — Our lignite/coal fueled generation fleet capacity totals 3,850 MW. Maintenance outages at these units are scheduled during the spring or fall off-peak demand periods.

We satisfy all of our fuel requirements at the Oak Grove generation facility with lignite that we mine. We meet our fuel requirements for the Martin Lake generation facility by blending lignite we mine with coal purchased from multiple suppliers under contracts of various lengths and transported from the Powder River Basin to our generation plants by railcar. In 2017, approximately 53% of the fuel used at the Martin Lake generation facility was supplied from surface minable lignite reserves located adjacent to the facility and dedicated to it.

Natural Gas — Our natural gas-fueled generation fleet capacity totals 7,497 MW. In April 2016, we acquired La Frontera Holdings, LLC the indirect owner of two CCGT natural gas fueled generation facilities located in ERCOT. The facility in Forney, Texas (8 units) has a capacity of 1,912 MW and the facility in Paris, Texas (6 units) has a capacity of 1,076 MW. In August 2017, we acquired a facility in Odessa, Texas (6 units) with a capacity of 1,054 MW. The acquisitions diversified our fuel mix and increased the dispatch flexibility in our fleet.

We also operate combustion turbine (CT) facilities at Morgan Creek (6 units), Permian Basin (5 units), DeCordova (4 units) plant sites and steam facilities at Lake Hubbard (2 units), Stryker Creek (2 units), Graham (2 units) and Trinidad (1 unit) plant sites. The CT and steam plants are peaking units which provide us the ability to meet increased demand from our retail customers during high market price intervals with available generation capacity and provide other wholesale opportunities.

We satisfy our fuel requirements at these facilities through a combination of spot market and near-term purchase contracts. Additionally, we have near-term natural gas transportation agreements in place for all of our sites to ensure reliable fuel supply.