CARACAS, Saturday February 27, 2016 | Update

National power grid nearing collapse

Unavailability of 60% the of thermal generation park, rising domestic energy demand and water levels at the Guri Dam down to record-low levels are the real causes of the crisis

Saturday February 27, 2016  12:00 AM
Power rationing is not new for Venezuelans. Over the past fifteen years there have been some crises, such as that of 2009-2010, that have forced Venezuelans to adapt their lifestyle to power outages. What is new, however, is the seriousness of the current situation which, according to some experts, is expected to get worse over the next two months if the necessary measures are not taken immediately.

To major general Luis Alfredo Motta Domínguez, the Minister of Electricity and President of the National Electricity Corporation (Corpoelec) - a state-owned holding company created in 2007 to consolidate the power sector - the current crisis is a one-off problem due to the extensive drought associated with the recurring weather phenomenon commonly known as El Niño, which has caused water levels in the Central Hidroeléctrica Simón Bolívar (aka the Guri Dam) to drop to record-low levels.

It is worth noting that that the Guri Dam (with an installed capacity of 10,000 MW), located in Bolivar state, is the largest reservoir in Venezuela. Some 60% of all electrical power generated in Venezuela originates in the Guri dam and the other hydroelectric plants built across the Lower Caroní River, namely: Caruachi (2,200 MW) and Macagua (2,200 MW).

Unlike Motta Domínguez, the experts consulted for this article believe that the ongoing crisis is structural in nature, involving the cumulative effect of multiple factors over the past 17 years that have led to the serious deterioration of the national electricity system (NES), affecting the quality of life of Venezuelans.

According to a diagnostic assessment of the electricity sector submitted to the National Assembly last February 5 by engineers with the Ricardo Zuloaga Group – a team of experts  dedicated  to  the  analysis  of  the  behavior  of  the national electricity system - the crisis that has started over the years of revolution has evolved to the point that the electricity sector went from providing a continuous, reliable service in 1999, the year when the current regime came to power, to deterioration in service with frequent power outages and interruptions in 2007, and finally to a scenario of continued power rationing in 2016.

A multifactorial crisis

To hydraulic engineer Jesús Gómez Medina, a member of the Energy Committee of the National Academy of Engineering and Habitat, the current electricity emergency is "the result of 17 years of misguided policies, sheer ignorance of the national electricity system, lack of professionalism and negligence."

Gómez notes that planning systems in the electric field began in the mid-1940s, and that over four decades consistent national electricity system expansion plans were implemented to achieve coverage of over 90% of the country with excellent reliability. "These projects were abandoned and no new plans relating to the construction of electrical plants and power stations, including keeping up the grid expansion with population growth, were ever launched."

Electrical engineer Miguel Lara Guarenas, former general manager of Venezuela's state power agency Operation of Interconnected Systems (OPSIS) shares Gómez's view. He further states that the current situation is a direct result of "the management model applied to the electric power sector," which favors improvisation, and of a number of government decisions, including the replacement of electrical industry professionals by personnel without knowledge or experience; lack of proper maintenance; and the suspension, postponement or delay in the completion of several grid expansion projects.

An example of this is the Manuel Piar Hydroelectric Power Plan (aka the Tocoma dam), built across the Lower Caroní River. Gómez points out that this is the only new plant built in the country, albeit with a five-year delay. It will provide 2,000 megawatts (MW) of energy, and is currently in the filling stage.

Another example is the Las Cuevas dam on the Doradas River (Táchira state, east) part of the second stage of development of the Uribante Caparo Hydroelectric Complex. Gómez notes that this development was planned back in the mid-1980s, but its construction has been postponed several times.

For its part, engineer Lara Guarenas, who is also a member of the Ricardo Zuloaga Group, adds to the list of government bad decisions the lack of rehabilitation of thermal power plants, the freezing of electricity rates, bureaucracy and the Cubanization of the sector,  partisanship of Venezuela's state-run National Electric Corporation (Corpoelec), and the opacity of information.

And whose fault is it?

Both Gómez and Lara Guarenas coincide in underscoring the fact that El Niño has been wrongly blamed for the crisis. They argue that dams and reservoirs are built and designed specifically to store water to tide over from times of excess to times of deficiency.

They also note that models are run by a variety of international institutions to predict the probability of the occurrence of El Niño so that countries may put in place measures to manage the hazards before and as they occur. One such measure, as the diagnostic assessment from the Ricardo Zuloaga Group rightly points out, is to increase thermal generation and reduce hydroelectric generation in order to conserve water in the reservoirs.

The crux of power shortage

Currently 67% of the energy produced in the country is generated by hydropower. This figure accounts for only 45% of the national electricity system, with the remaining 55% coming from thermoelectric generation, according to figures provided by engineer Jesús Gómez. These percentages reflect that installed thermal capacity exceeds hydroelectric capacity; still, Venezuela remains dependent on the Guri, says Lara-Guarenas.

From 2009 to 2015 the revolutionary government spent very large sums of money in a thermal park having a generating potential similar to that of Guri; that is, the national electricity system capacity was increased by almost 10,000 MW. But, of that total only 40% is currently available because most plants are obsolescent and non-operational due to lack of maintenance. Such is the case with the Planta Centro thermoelectric plant, located in Morón (northern Carabobo state). This plant is the country's largest and has an installed capacity of 2,000 MW, but it has not generated a single watt of power since last December 17, according to Lara. Additionally, those thermoelectric plants that are functional are operating below their installed capacity.

With the addition of these new megawatts, installed capacity of the national electricity system increased over the years of revolution by approximately 75%, from 19,696 MW in 1998 to 34,400 MW in 2015, according to estimates by Lara. Despite this supply level, accounting for almost twice the demand for electricity consumption in the country (18,300 MW), only 17,220 MW are available, i.e., there is a deficit of 1,080 MW.

To the increase in demand and the unavailability of 60% of the installed thermal power capacity, another factor is added: water levels at the Guri dam fell to record-low levels for an early dry season, and this will intensify over the coming two months, according to experts.

As explained by Gómez, the Guri level has decreased because the Lower Caroni hydroelectric plants have had to work beyond the safe operating margins ensuring their long-term performance.

"If the safe operating flow rate is 4,500 cubic meters per second (m3/s), that means water is being turbined at a rate well beyond that level, which coupled with the reduction of the flow contributions from the Caroni River, has brought the decline in levels of the Guri to a situation that I call 'of no return' where the collapse of the national electricity system is virtually irreversible," says Gómez.

According to figures accessed at Corpoelec website, the water level of the Guri dam stood at 250.52 meters above sea level (masl) by February 18 2016, which means that the dam is already operating within  what some engineers call "the zone of collapse or critical zone", i.e.,  less than 252 meters above sea level, says Gómez.

This is particularly worrying because the minimum operating threshold is 240 meters above sea level, at which height the turbines stop working. However, at heights of 244 masl the turbines risk being damaged since, according to experts, as the water level goes down, air bubbles can go in the turbines. These bubbles create pressure waves which are at high frequency, which lowers the efficiency and damages the turbines.

Gómez explains that hydroelectric plants do not suddenly stop operating, but turbines gradually lose their ability to operate as the water level falls.

The projection is ominous, to say the least. Estimates by members of the Venezuelan Engineers' Association (CIV) suggest that by May 18 2016 the level of the Guri will be at a height of 239.90 meters above sea level. On May 18 2015 the height was 249.56 meters above sea level.

Against this background, the question that naturally follows is ‘how many days left before the Guri stops operating altogether?'

According to a curve chart calculated by the state-run power utility Electricidad del Caroní (Edelca) in 2008 to determine the Guri's remaining days generating at 100% of demand, the reservoir would be left about 50 days of operation counting from February 18, when it was at 250 meters above sea level. Which means that, under normal conditions (that is, without rationing), the Guri would have water to operate until the first week of April.  The rains are expected to begin in mid-May, though.

Although the Edelca study was conducted eight years ago, Gómez notes that the curve serves as a reference because it sets a scale depending on the water level.

This is why, in order to maintain the service until May, the competent authorities will have to resort to a more stringent rationing plan than the one applied at the end of 2009. Hence measures like energy rationing during rush hours to shopping malls, hotels and restaurants throughout the country. However, both Lara and Gómez believe that energy saving from this measure would be derisory, because it only accounts for a very small percentage of the maximum power during those hours.

A negative verdict

In view of the complexity of the above, the Ricardo Zuloaga Group has no hesitation in saying that the national electric system shows a "failure in operational generation capacity, which is more serious than in any of the previous years."

The group of engineers argues that the problems in the national energy sector are compounded by the difficulties facing the hydrocarbons sector - the power sector needs to be supplied with gas, diesel and fuel oil to generate electricity and, in turn, the oil industry needs electricity to carry out its operations.

Finally, the report submitted to the National Assembly provides a range of recommendations to alleviate the crisis in the short run, including increasing the availability of the thermal generation park from 40% to 60% in order to minimize electricity rationing.

In the long run, engineers recommend a complete change in the management model applied to the electric power sector.

Twitter: @alejandramhf

Translated by Sancho Araujo