April News: Spain/Portugal Blackout, TX First Texas 765 kV transmission lines, No Turbines available till 2030! Issue #9
Spain/Portugal grid fails; 60 million people without power. Texas PUC approved 765 kV transmission lines for more reliable grid. But gas turbine lead times delay adding generation capacity till 2030.
Updated May 5, 2022
The last 10 days of April have been busy as rains fill lakes and rivers. Floods end long drought. The burn ban was lifted April 16th for Wichita County. By the end of April Wichita Falls rainfall pushed the year to date rainfall totals to 12.86” , well over the historic norm of 7.12 inches. April left wet with a final 2.01 inches of rainfall Wednesday April 30 breaking a record from 1951.
This issue covers the following topics:
· Monday (04/28/2025) Spain and Portugal lost power mid-day. What happened and could it happen here? Twice as many people live in the two countries as Texas; the area of both countries is smaller than that of Texas.
· Last week, a few more Texas Energy Fund participants were unable to meet schedules or arrange all the project funding necessary to bring more gas turbine generation capacity to market by 2030. Turbine manufacturing capacity is full; expansion of manufacturing takes time.
· April 24, 2025, Texas PUC approved Texas first 765 kV transmission lines. One 765 kV transmission route, can deliver the power of six 345 kV lines. This next generation backbone for power transmission will relieve congestion between south and west Texas as generation capacity will be able to send power to the urban triangle of DFW, Houston, San Antonio. Necessary to support the power demand forecast for 2030, while reducing energy losses as compared to legacy 345 kV technology. Think of 765 kV as the next-gen energy interstate express lane.
If you don’t remember, the last issue detailed the new demand forecast for 2030, here is the one-chart summary.
Next Tuesday, May 6th we will be attending the 2025 ERCOT Innovation Summit in Round Rock, Texas. Coverage in coming issues.
Now let’s dive into today’s newsletter.
Spain and Portugal Blackout, April 28-29, 2025
60 million people in Spain & Portugal lost power Monday, April 28, 2025
Monday at 10:33 GMT, Spain (12:33 CET, Central European Time) and Portugal (11:33 am WEST, West European Summer Time) suffered a blackout of electric power that left over 60 million people without power overnight. Authorities have ruled out cyberattacks.
Real-time grid data suggests the rapid loss of 15 gigawatts of load, without a matched reduction of power generated, overwhelmed the response capability of the Spanish grid. The system responded by disconnecting generators from the grid, as designed. Circuit breakers tripped throughout the system, preventing non-recoverable failures; this allowed the generators to be restarted after problems are corrected.
As the Spanish grid is connected to grids of adjacent countries for system reliability, these issues propagated into the grid that powers Portugal. The connection to the French grid disconnected, as designed, before the blackout affected France.
Net results, the population of Spain and Portugal (the Iberian Peninsula) had no electricity till the systems were restarted and back on-line Tuesday (04/29/2025) morning at 11:15 GMT.
Black-Start Recovery
This cascading collapse of the grids in Spain and Portugal is a worst case power event. When all the generators disconnect, a tedious process is necessary to bring the generators back on-line. Each generator must match frequency with all others on the grid.
Adding power to the grid with additional generator capacity, also requires that equal power must be delivered to loads – homes, industry and manufacturing.
Stable external power is needed to reboot the system. In this case a power connection to France, provided enough energy to bring a few generators on-line again. In industry parlance, this is a “black-start” .
As incremental power comes from a restarted generator, this additional power is used to then “black-start” additional generators. Reliable grid operation requires each generator be synchronized to the exact phase of all other generators. Standard European power frequency is 50 Hertz (Hz); differing from the standard US frequency of 60 Hz.
Loss of 60% of the load in Spain
Reports during the event reveal system problems occured as 15 gigawatts of load dropped from the Spanish grid in five seconds at 1033 GMT said the Energy Ministry Monday evening. This dropped load represented 60% of the total power demand.
The Spanish grid operator REE (REDE.MC) noted this loss of load demand exceeded the design margins. Circuit breakers through-out the grids of Spain tripped as generators disconnected. These automatic grid responses protect other generators from non-recoverable equipment failures.
Other connections to France disconnected also to protect “good” generators on their local grids from failing. Unfortunately the faults propagated into the grid of Portugal causing a blackout in both Spain and Portugal.
Three hours before the blackout small fluctuations in voltage were reported by sensors deployed by Whisker Labs from Maryland. CEO Bob Marshall said Tuesday that the software developer has a couple dozen sensors in homes in and around Madrid monitoring the grid.
ERCOT grid similarities
We assume the connection to the French grid serves a similar purpose to the four connections to adjacent North American grids via DC tie lines to the ERCOT grid.
The ERCOT “tie-lines” connections allow DC power to flow between North American grids. This power can be used to restarting one grid using “good power” from another after such a catastrophic blackout.
These ERCOT tie lines can provide about 200 megawatts transferred in or out of adjacent grids. Note total power of the grid is over 50 gigawatts.
Most days, this transfer of power supports business transactions transfering modest amounts of power between entities. But in the case of a blackout, this “tie-line” of reliable power coming into the ERCOT at the proper frequency of 60Hz can be used to sequentially bring offline generators up to the proper rotational speed and then reconnect them adding additional power to the grid. As an added generator pumps power out, load must be connected in matching power levels for reliable operation.
Consider the balance scale graphic below, where power in must balance power out to loads. With too little a load, frequency surges, speeding the rpm (rotations/minute) of all generators on the grid.
Could this happen in Texas to the ERCOT grid?
Many have blamed renewable energy sources like wind and solar as these power intermittent sources depend on wind and sun, respectively. Both wind and solar generate DC power that is then converted electrically to the grid levels.
As this power is electrical converted, as compared to thermal generators where heavy armatures spin. The spinning inertia smooths small frequency and voltage swings as loads and generators connected and disconnect randomly and independently from the grid.
Source: NREL, ERCOT: Reference footnote 11
With the ongoing deployment of renewable power, IBR resources are a growing percentage of the power for grids throughout the world. Note the chart below highlights Spain’s high adoption rate for solar and wind. Spain has not added BESS capacity as aggressively as others; ERCOT is a leader in BESS second only to California with installed BESS capacity.
ERCOT has seen lots of added Wind and Solar additions as shown below
The rotating generators have inertia due to the armature’s rotating mass.
ERCOT manages reliability with a set of ancillary services that maintain reliability even if a two-reactor nuclear power plant drops offline as long as sufficient system inertia of 88 MW (formerly 100 MW) of rotating geneneration capacity in reserve for rapid response.
This Primary Frequency Response, (PFR) is a contingency reserve provided by thermal generators governors that can respond to drops in frequency as load increases. PFR resources respond to grid demand in 10 to 60 seconds.
If less than 88 MW of thermal generator (rotating) inertia is available, voltage and frequency oscillations may occur on the the grid. Note the similarity to the oscillations observed on the Spanish grid a few hours in advance of the grid collapse and blackout.
ERCOT has required Grid Forming (GFM) support for inverter-based resources (IBR) for many years, leading the industry in tackling IBR and system reliability. This is a superior inverter strategy as GFM can stabilize like inertial power from spinning reserves. ERCOT added Fast Frequency Response, a new ancillary service, leveraging GFM IBR capacity. BESS systems can respond in half a second.
FFR from BESS has lowered ERCOT’s critical inertia point from 100 MW to 88 MW. This is the lowest amount of synchronous generation (rotating generators) required to arrest frequency decline.
For those wanting a deeper understanding of the technical details, consider reviewing this research from 2023, titled, Inverter fast frequency response is a low-cost alternative to system inertia: https://doi.org/10.1016/j.epsr.2023.109422
In practice what is the difference for grid operation between GFM (Grid Forming) and GFL (Grid Following)? GFM can dampen the oscillations from loads and generators connecting and disconnecting. As well, GRM overcomes gusty winds and clouds shading solar array from oscillations as the power output from wind and sun varies.
Consider these two cases of low frequency oscillations, less than 2.5 Hrz and oscillations between 2.5 Hz to 2.5 kHz as compared below. Grid forming IBR (Inverter Based Resources) are more robust as show in the upper half of the charts below even as oscillation frequencies vary.
Look at the data from Spainish grid operator Red Electrica below. This shows the earlier oscillations and how those variances presented less than perfect power to loads. In the US, (Virginia and Texas), Data Center loads need smooth continuous power, these oscillations from GFL technology shown on the Red Electrica provided Spanish Grid data logs, could have caused sensitive loads like data centers to disconnect.
As well the addition of large data center load require stable frequency and power. Grids in Virginia and Texas have seen rapid load disconnects to protect the sensitive computer circuitry from catastrophic failure. More specific requirements for disconnect process have been added to connection agreements to make sure reliable operation of the grid supports all users.
ERCOT addresses this weakness by specifying the attach and disconnect protocols for loads and has a large capacity of BESS (Battery Energy Storage Systems) – reference the fuel mix chart below.
More detail in later issues; in the interim, additional details may be referenced here: https://www.reuters.com/technology/big-techs-data-center-boom-poses-new-risk-us-grid-operators-2025-03-19/
Grid system operators in other regions with high penetration of IBRs have GFM-BESS deployed or under construction to support their grid reliability needs. (e.g., Australia, UK, Hawaii, Finland, Germany). Reference: https://www.esig.energy/working-users-groups/reliability/grid-forming/gfm-landscape/projects/
ERCOT has an IBR Working Group (IBRWG) of experts focusing on IBR and how to best deploy renewables without risk to the grid, customer demand or other generating equipment.
Grid Forming reacts and overcomes the oscillations quickly providing stable smooth power. As shared in the IBRWG, ERCOT does see benefit from grid forming technologies:
· Better transient dynamic voltage and frequency response, particularly in weak grid conditions
· Reduction of the risk of IBR tripping or unstable operation
· Increase of GTC (Generic Transmission Constaint) limits which can remove generation curtailment due to stability constraints.2
When comparing new generation choices the Landed Cost of Energy (LCOE) for differing fuel sources compares $/MWh. Utility scale wind and solar continue to be the most competitive forms of new electricity.
ERCOT is leading the industry in deploying renewables while not compromising the reliability of the delivery of electric power.
Supply Chains delay new Gas generation capacity to 2030
The 88th Legislature (2023) created the Texas Energy Fund, with an amendment for the state constitution approved by the voter November 7, 2023.
Initial funding of $5 billion is intened to help stimulate investment in new gas generation plants, “peakers.” Peakers can quickly be dispatched to meet the peak usage hours (~ 7am-9am and 5pm-8pm).
While seventeen companies have applied for access to these funds, seven have dropped out of the program; two having difficulty in closing all the business details, while others cannot get delivery of turbines within required timeframes as defined by the legislature and Texas PUC.
At the 2025 POWERGEN International conference mid-April in Dallas, “Gas turbines were dead in 2022,” Siemens Energy North America President Rich Voorberg told the Opening Keynote audience. “We will never get a regulator to approve gas turbines ever again in our state,” he recalls a colleague saying.
“We can’t make enough gas turbines (GT) to support this market,” said Voorberg in his keynote. Simple-cycle and combined-cycle GT are in high demand for utility scale power generation as well as small turbines as all leverage the same supply chain.
At the same conference Solar Turbines (Caterpillar subsidiary), Mitsubishi Power, and joined GE Vernova in sharing similar lead time constrained delivery schedules. These largest manufacturers warn that procurement discussions should start seven to eight years ahead of desired turbine deliveries. Suppliers are dramatically expanding production.
As an example, GE Vernova will spend hundreds of millions to ramp up additional US manufacturing facilities. GE Vernova executives also shared that 9 GW of reservations for gas turbines had been signed in a single one-month period. GE Vernova also shared that for the first 9 months of 2024, they had 14.1 GW in turbine orders, compared with 7.4 GW for the same period in 2023.
Texas PUC approves next-generation 765 kV transmission lines April 24, 2025
Extensive reviews by ERCOT, TSP and PUC of Texas resulted in the Texas PUC unanimously approving a 765 kV Transmission backbone that addresses demand particularly in the Permian Basin Region, as well as dramatically adding capacity around the state to enable the future growth forecast by 2030.
“The PUCT is fully committed to building an ERCOT grid that will serve Texans reliably for decades to come,” PUCT Chairman Thomas Gleeson said. “Extra high voltage lines are more efficient and strengthen reliability. Because each line can carry more power, fewer lines are necessary to serve the needs of the Permian Basin Region, meaning less disruption to Texas landowners, natural habitats, and landscapes. Our priority now is ensuring utilities execute these projects quickly and at the lowest possible cost to Texas consumers.”3
ERCOT and the TSPs estimate the extra high voltage plan could cost 22% more than the lower-voltage 345 kV alternative; however, this 765 kV decision provides many long-term benefits. Higher voltage lines can carry more power and meet higher levels of demand as the state continues to grow, reduce expensive congestion on existing transmission lines, and saves money in the long-term by avoiding the need to build new transmission lines to catch up to future demand.
Today’s congestion and transmission limitations contribute to power losses paid for by electric users. The 765 kV transmission system will reduce systemwide transmission losses by about 5%, approximately equivalent to adding a 128 MW thermal unit operating at 50% capacity factor.
ERCOT’s analysis also show the 765-kV system enhances transfer capability by an additional 600 MW to 3,000 MW across various scenarios evaluated in the analysis. This higher transfer capability could also provide a greater range of siting options for both generation resources and large loads.
“The State of Texas is experiencing significant levels of population and economic growth, and the Public Utility Commission’s action today will help ensure that the electric grid is better prepared to meet the growing demand on the electric system,” said Judith Talavera, AEP Texas president and chief operating officer. “AEP Texas is proud to play a role in this transformative step for our state, building one of the first 765-kV transmission lines in ERCOT, and to continue to provide safe and reliable service for our customers.”
American Electric Power, AEP Texas’ parent company, owns 2,110 miles of 765-kV transmission lines, more than any other transmission system in North America.
AEP’s experience with 765-kV began in 1961 with the installation of an experimental 750-kV transmission line at AEP’s test facility near Apple Grove, West Virginia. In 1969, AEP energized the world’s first operational 765-kV transmission line between Kentucky and Ohio, marking the highest installed voltage line at the time. Today the AEP 765-kV network has grown to over 2,200 miles and 30 substations across six states.
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https://www.ercot.com/files/docs/2020/11/27/The_Use_of_GTCs_in_ERCOT_July_2020.pdf