The Foundations Of The Electricity System

Mon, 02/25/2019 - 16:06

The transmission and distribution segments are essential for providing electricity supply across the country. As renewables take the lead in the country’s energy mix, their isolated locations in relation to the National Electricity System (SEN) mean new lines are needed to ensure every region has access to electricity. Everyone knows and understands this but getting it done is another matter.
“The Ministry of Energy’s PRODESEN 2018-32 establishes the requirement for new transmission lines but these have not been built at the needed pace. This infrastructure has to be fortified, not only to transmit energy from generation facility to the consumption point but to design a robust electricity network that allows the exchange of energy between regions,” says Leopoldo Rodríguez, President of AMDEE.
According to the Constitution, transmission and distribution activities are considered strategic areas and are reserved for the Mexican state. Even though, Article 2 of the Electricity Industry Law (LIE) indicates that while the state will maintain its titularity, contracts can be signed between particulars in compliance with the respective legal framework. The Energy Reform opened the door for the generation and commercialization segments to participate in a free market regime, liberalizing the two ends while leaving electricity transportation system in the hands of the state, and CFE in particular, through its CFE Transmisión and CFE Distribución subsidiaries.
“During (the Peña Nieto) administration, we opened an opportunity for the industry to participate directly in transmission and distribution infrastructure projects,” says Fernando Zendejas, former Deputy Minister of Electricity. He adds: “At the moment, there are two important tenders on the agenda regarding the construction of transmission line projects. The first will be in association with CFE for the Ixtepec-Yautepec Transmission Line. The second is a private project involving the interconnection between the National Interconnected System and Baja California. The latter will be the first project in the country’s history to install DC lines for electricity transport.”
But the new administration threw a spanner in the works when it took power in December, delaying the auction processes for these strategic projects along with the fourth long-term electricity auction. CFE will not address the topic in 2019. “The 2019 project of budget outflows does not contemplate resources for the transmission segment and it is a topic that needs to be revised,” says Guillermo García, President Commissioner at CRE.
Ixtepec-Yautepec Transmission Line: In 2015, the Ministry of Energy awarded CFE the Ixtepec–Yautepec Transmission Line project. This DC line will transport 3,000MW from the Isthmus of Tehuantepec region to the rest of the country. The project consists of 1,221km of line circuits that will carry a 500kV voltage from the municipality of Ixtepec to various consumption points located in Veracruz, Puebla, Morelos, State of Mexico and Mexico City. “Oaxaca is Mexico’s leader in renewable power generation, with the most installed capacity from wind energy in the country. It hosts 27 wind farms that supply 2.3GW to the national grid. With this project, Oaxaca will be able to double its installed power capacity and the electricity generated will be transmitted to other regions of the country,” says José Luis Calvo, Minister of Environment, Energy and Sustainable Development at the State of Oaxaca.
Baja California – National Interconnected System Transmission Line: This project will interconnect Baja California’s electrical system with the National Interconnected System (SIN) by being the first DC transmission line in the country. This region is the only electrically-isolated system in Mexico and holds significant potential for the development of renewable energy projects. The transmission line will start from the municipality of Seri in Hermosillo and will travel 1,400km toward the municipality of Mexicali in Baja California. Besides interconnecting the entire country, Baja California remains a strategic region due to its closeness to the US. “To date, we have 11 interconnections with the US: six emergency connections and five for continuous supply. The idea is to have them operating as a connected market,” says García. Tijuana-Miguel and La Rosita-Imperial Valley are the two interconnection points that trade electricity with California Independent System Operator (CAISO). On previous occasions, this frontier interconnected system has supported energy blackouts in both countries.
In 2017, the latest data available show that Mexico registered a peak power demand of 43,319MW. This total increased 5.9 percent from 2016. 2018, however, registered a total generation capacity of 75,685MW, with 70.5 percent coming from conventional energy sources and the rest from clean energy sources. The interconnection of new plants, as well as the associated load centers, combined with greater demand suggests the necessity to modernize and expand the current transmission and distribution infrastructure. At the end of 2017, the interconnection capacity of the 53 transmission regions totaled 76,697MW. The northeastern region led demand and experienced 14.8 percent growth versus 2016.
Regarding the expansion of transmission lines, 2,909km were added in 2017, for a total 107,042km. Considering an annual demand growth of 2.9 percent, CFE Transmisión’s 2018-2022 Business Plan projected a total investment of MX$100 million for this period. From that amount, MX$88 million will be destined to expand the transmission network and the rest will be focused on modernizing transmission lines and substations. “The system is modeled according to the necessities of power generators and load centers. Distribution does not present many problems for dispatch; issues come at transmission level,” says Eloy López, Director General of ISEBSA. He adds: “Large load centers are inherently difficult to recalibrate. Due to these difficulties, instead of recalibrating or increasing the capacity of the existent lines, CENACE is calling for the installation of new lines to modernize the grid, using the old scheme as reinforcement.”
The electrification of the energy system is becoming more tangible. In a recent study carried out by AMDEE, the Commission of Private Sector Studies for Sustainable Development (CESPEDES), the Mexican Association of Solar Energy (ASOLMEX) and Iniciativa Climática de México, it was determined that by 2024 there should be 300,000 electric vehicles in Mexico. “This projection offers a sizable opportunity for private companies versed in transmission networks to provide the required investments to prepare the country for this technological revolution,” says Marcelino Madrigal, Commissioner at CRE.
In this sense, energy storage technologies also play an important role for grid stability. Gradually, the energy system will be composed of renewable sources, peaker plants and energy storage facilities that will balance the consumption profiles with support of the electrical infrastructure. “Batteries are valuable elements of the electricity system. In case of a failure in the generation facility, batteries could supply energy for a while. This technology also provides voltage and frequency regulation, providing support to the grid and reducing the need for transmission lines in several cases,” says Leopoldo Rodríguez, President of AMDEE.