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SKYELECTRIC BLOG

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ENDING LOAD SHEDDING IS HARD

By: Ashar Aziz

Ending Load Shedding and Unscheduled Grid Outages – A Lot Harder than it looks

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fficials in Pakistan, and also many other developing countries, grapple with the imbalance between electricity supply and growing demand – which leads to both scheduled and unscheduled load-shedding, a polite word to describe grid outages and loss of power.

 

Governments and utility officials are under pressure to make a swift end to scheduled and unscheduled power outages in the face of increasing public outcry and protests, and therefore frequently promise that a solution is at hand. The reality is such that the problem of load shedding is far more complex than it would appear on surface.

 

The simple approach is to try to estimate peak demand, subtract from that current power generation capacity to deduce the gap, and then attempt to quickly build power generation plants that plug the gap between generation capacity and perceived peak demand.

 

Besides adding new power generation plants in a timely manner, there are two very serious and complex issues to consider, both of which are hidden under the surface of the relatively simple power generation supply-demand imbalance equation.

The first problem is the power transmission and distribution grids. Transmission and distribution grids in developing countries, such as Pakistan, generally have limited capacity and aging equipment that may be unreliable and inefficient in its ability to deliver power without significant losses.

 

Transmission and distribution capacity is critically important if power generation capacity is to be increased.

 

Transmission and distribution capacity is critically important if power generation capacity is to be increased. A simple analogy is that of a water pipe that has a limited capacity to provide water at a certain rate. If the rate of water movement (namely power) is to increase, by increasing the water supply and water pressure at the back of the pipe (namely more power generation plants), but if the pipe capacity is not increased proportionally, it will simply burst when more water is pushed through it. The same is true for electrical power generation and distribution. All of the various long distance high voltage transmission lines, and all of the sub-stations and distribution transformers that supply power to various neighborhoods have to be upgraded in order to

carry the increased power. In the absence of transmission and distribution power capacity upgrades, the power grid will become unstable if more power is placed on it than the grid has the capacity to deliver, and there will be tripping due to distribution capacity overload. So adding more power plants, without proportionally increasing the grid transmission and distribution infrastructure, will not solve the problem. Transmission and distribution infrastructure upgrades are expensive and complex, especially in the middle of large sprawling urban environments, where space and wiring constraints may make such upgrades difficult to do.

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However, there is another issue, and one that is the actually harder to deal with. This is the difficulty of gauging “peak demand”. Peak demand is not a static number but rather a constantly moving target. And the biggest irony of peak demand is that the greater the power supply will become, the greater the peak demand will become in countries that have chronically low per capita use of electricity. One could ask, why would power demand increase if supply is increased? Shouldn’t it be the opposite? The answer has to do with feedback loops in national economies, especially those constrained by chronic power shortages.

Greater power supply is directly correlated with higher economic output as measured by GDP per capita. Greater economic output means greater employment, increased business and industrial activity and more prosperous life styles. Greater business and industrial activity requires more power and therefore greater power demands. This relationship holds almost linearly, when businesses and industries have been historically hampered due to chronic power shortages. So, the biggest stumbling block to ending load-shedding is addressing the issue with simple math. That is, solving the

supply-demand imbalance by taking a current snapshot of peak demand, and building additional power generation capacity to meet that demand. The demand is an increasing number because the increase in supply paradoxically leads to increasing demand, due to increased economic activity and greater prosperity with a greater energy supply. So, after adding a bunch of generation capacity, the system will actually again have a big supply-demand imbalance, due to the increased demand, and therefore the country and the grid will be back to the initial state of load-shedding.

Let’s look at this situation in another way, by analyzing electricity consumption per capita, its association with GDP per capita, and the state of load-shedding or not in different countries. Pakistan’s current electricity consumption is approx. 400-450 units per year per capita. Let’s say we were to double this to 800-900 units per capita per annum. Would this end load-shedding? Pakistan’s neighbor India has exactly this kind of electricity consumption, between 800-900 units, and it still suffers from chronic power outages and shortages.

So, it’s easy to predict that doubling current capacity from 400 to 800 will not end load-shedding, because India, with a very similar weather profile and electricity consumption profile, has not succeeded in ending load-shedding or other grid related instabilities at double of Pakistan’s electricity consumption per capita per annum. In fact, hundreds of millions of people in India have little to no access to electricity even at double of Pakistan’s current electricity consumption per capita.

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By performing the same analysis for countries around the world that don’t suffer from chronic power shortages, it is easy to assess that one has to increase supply to approx. 8-10 times Pakistan’s current capacity, before any kind of threshold event will be reached, where increase in supply won’t result in a proportional increase in demand. This would be the plateau value of consumption to ensure a reliable and continuous power supply. This plateau value of consumption is approx. 4000-5000 units per capita per annum, and this is where the near linear relationship between consumption and GDP per capita no longer holds. It should also be obvious that increasing the power supply, and associated grid transmission and distribution capacity, by a factor of 8-10x is a herculean task, especially in a very constrained time frame. While Pakistan may well get to that state of continuous availability of power to the vast majority of its population, that state may not be in the near or mid-term future. In fact, some experts predict that we may not reach that state till after 2030.

 

So, while officials and planners may very well be genuine and sincere in their efforts to solve the energy crisis, it would be wise to try and understand the long term system wide issues related to power. Power is distributed through a complex, under-provisioned and potentially fragile distribution infrastructure in countries like Pakistan, and one needs to understand the relationship between power and the country’s economy and life-styles of the people. The intrinsic economic feedback loops will continuously unlock suppressed demand when supply is increased. It is necessary to consider all of this before making promises to end load-shedding and outages – promises that may very well be impossible to keep.