Sri Lanka’s power supply, blackouts, and how to prevent them

Sri Lanka recently had a nationwide blackout that cost millions, and even compromised its security. A blackout may be compared to a sudden heart attack, leaving a debilitated individual. This was the fifth “heart attack” suffered by the grid since the end of the Eelam wars, with blackouts in 2009, 2015, twice in 2016, and on 17th August 2020. So we have a chronically sick patient.

Letting the Cat out of the Bag.

The CEB authorities have conveniently ascribed the problem to “human error”. The patient got the 5th heart attack accidentally, because he yawned too hard – but we don’t mention his chronic condition!

Dr. Tilak Siyambalapitiya has written to The Island newspaper (19-08-20) about the “anatomy of the blackout”. He suggests that the CEB grid can be perturbed by small erratic inputs from solar and wind energies, making the grid unstable!

The SL-power grid provides about 2000 MW. However, even if many solar installations, wind farms etc., contributed erratically to the grid, they might hardly add to 10 MW within a time interval of a few seconds. A few seconds is a “large” time for electrical systems that react in milli-seconds or faster. A 10 MW fluctuation in a 2000 MW system is just a half percent fluctuation!

So, the “human error” is merely the proverbial straw that broke the camel’s back. The 2000MW system should have a peak to trough daily fluctuation of, say, plus or minus 500 MW, and these are “scheduled changes” handled by the grid using set procedures for load adding and load shedding.

The CEB power system is not a smart grid controlled by an intelligent set of algorithms that deftly and rapidly manipulate well maintained “on-load tap” changers, shunts, relays and switches. Instead focusing on such realities, we are told that a superintendent accidentally earthed a live line and the system collapsed, almost like a cheap Wesak pandol without a fuse built by the village “Baas”. The “Baas” and the CEB technicians also work without written-down procedures. Is the CEB “just managing”, riding the cusp of the blame for neglecting to modernise it and maintain it.

There is hardly a scientific paper or engineering report published by the CEB scientists in peer-reviewed technical journals of, say, the IEEE, that would report the evolution of the CEB’s control systems, its many blackouts etc. In effect, the officials have worked like “Baas Unnaeheys”, with no Research and Development (R&D) or establishing a learning curve. Although five blackouts have occurred since 2009, does the CEB have “in-house” capacity to simulate such events? Its only “R&D” are to host an occasional student working with a University Professor to do research that costs a dime.

The CEB boasts of some 22 major hydro-electric stations. But it has not acquired the knowledge to, say, innovate a new pilot plant better fitted to the needs of the country. If such competence had been acquired, it could export its knowledge and win tenders in foreign lands!

So, the CEB is only an UNTHINKING beast that generates, transmits and sells power, and calls for tenders when needed within the standard frame of available “ready-made” power plants. Anything beyond that set path, even a modest roof-top solar panel, gives the creature a heart attack.

Is there a “Wealthy CEB Mafia”?

The public talks of “a power mafia leading a high life” in the CEB. The blackout has even been linked to conspiracies! A Derana TV discussion labelled the CEB a “fifth power” that can hold the country to ransom!

However, the CEB can point to successive governments that have scuttled their plans. Though building a power plant may take just a couple of years, the approval, tenders, acquiring land and licenses may add decades.

The government can change every five years. Sri Lanka periodically changes governments and the new politicians discredit and smash the plans of their predecessors. Power plants proposed in the 1980s have been cancelled, re-approved and new tenders called by politicians since the time of Premadasa, through Kumaratunga, to Rajapaksa and Sirisena a dozen times!

The CEB engineers can say, if we only had that “excess capacity” then these blackouts wouldn’t have happened! On the face of it, this might indeed be true. But this is irrelevant given Dr. Siyambalapitiya’s admission that the system cannot even handle a 0.5% power fluctuation from “un-monitored” sources like “solar and wind”.

We now understand the foot dragging of the CEB in incorporating wind, solar and bio-energy. The grid is an ad hoc patchwork of wires connecting a bunch of power stations in the simplest manner possible. It is a STUPID grid when a SMART grid that collects its own data and servo-controls the supply and demand is needed.

The engineers, taken individually, are technically capable well-trained people whose integrity must be accepted until proven otherwise. They are not political appointees like some secretaries to ministers. So, what has gone wrong?

How to correct the mess

Given the finances of the CEB, it MUST be guided by its own vibrant research arm with in-house research, pilot projects and research publications. If industries like Tea and Rubber can have their research institutes, how can the power sector which dominates Sri Lanka’s foreign expenditure not have one? The CEO’s of the CEB are unforgivably guilty of not establishing such a research arm. The first task of R&D should be to create a smart grid with automatic data collection at a large number of monitoring stations within months.

Unlike in the old days when power engineering was the strength of a power utility, today the Information Technology division plays a key role. The CEB R&D branch should work on new technologies like solar power. The public must not grudge high salaries and attractive perks to top engineers and researchers who produce new research, build pilot plants and usher in new technology. Here we are not talking of bureaucrats who spin narratives to justify ongoing failures.

How to cut costs, and boost hydro and solar power.

A large fraction (usually over 50%) of the cost of a unit of power goes for the generation step, and additional costs arise in transmission and marketing. The generation cost of hydro-electricity in Lanka is about Rs 2 to 4 per unit. Clean coal and dendro energy may cost Rs 12 per unit, while fossil fuels (LNG or Diesel) need Rs 20-30 per unit. Today, a unit of solar or wind energy may be less than Rs 10 for large scale installations. Of these, hydro, wind, solar, and dendro are the only environmentally acceptable energy sources.

Clearly the best option is hydroelectricity. Although most hydro sources are already tapped, there is at least a 30% increase possible with very little effort. The CEB is “gungho” for building floating (off-shore) LNG storage units and coupling them with pipelines dangerously passing through busy urban areas to deliver fuel to a new 300 MW power plant. And yet, it does not seem to be able to put floats and cover hydro-electric reservoirs to prevent the evaporation of the water that occurs day and night! Evaporation will get even worse with global warming. But the CEB has no plans for global warming.

So, preventing evaporation will rapidly increase the island’s power capacity by, say, 30% . Given some 22 major hydroelectric reservoirs with a surface area of about 1000 ha each, if 50% of the surface be covered using floats, 11,000 ha (110 sq km) are protected. It can be shown that the environmental impact is positive. The annual hydro-power of about 6000 GWh will rise to 8000 GWh when evaporation is cut. This is the cheapest and cleanest electricity!

Typically, sunlight can annually produce about 100-200 GWh per sq. km (100 ha) under Sri Lanka’s conditions. If solar panels are also placed on the floaters deployed to cut evaporation, then 1000-2000 GWh per annum of solar energy can be harvested, with no hassle about acquiring land rights. Any excess daytime energy can be saved by retaining the corresponding amount of hydro-head in the reservoirs, without sending the reservoir water down into the turbines. That is, solar electricity has been stored without batteries!

Of course, this kind of fine tuning and optimal control cannot be done using the “stupid” grid that is available to the CEB at the moment!

[The author has published over a hundred research papers on high-energy density matter and topics on laser-assisted fusion energy, often in collaboration with scientists at the French Atomic Energy Commission & Electricite de France, the US Lawrence Livermore Laboratory, and the US Los Alamos Laboratory.]

Source : island