Coal became the global workhorse of large-scale electricity in the 19th and 20th centuries. The discovery of oil and gas between the two world wars, the superiority of energy density in these fossil fuel cousins was a significant setback to the global coal market, not to mention the market entrance of radioactive uranium later on. The 1973 oil shock to the United States, the world’s single largest national economy, spurred a fresh momentum for coal. At that time, the US did not know how much natural gas it had or its extraction technology. Copycat economies, especially those with ample coal reserves of their own, followed the US’s example. The worldwide electricity share of coal grew from 30.3 percent in 1974 to a peak of 41.3 percent in 2007, but has been faltering since.
During the coal boom, the many ill-effects of coal electricity, from environmental destruction to greenhouse gas emissions to a lethal impact on human health became increasingly obvious, extensively researched and documented. Despite a growing toll on planet care and human life, coal was considered a necessary evil for cheap electricity and competitive industrialisation. Around the turn of the 21st century, it dawned on the more affluent and technologically advanced countries that coal was more of a historical burden than future necessity. The lure of the dirty watt began to rapidly fade.
PAKISTAN’S LATE ROMANCE
Pakistan was unable to mine coal in its heyday. The opportunity of coal from the Thar desert became a hot topic about a decade ago, ironically when the smarter economies started its retirement planning from their energy portfolios. The perception built around the Thar coal reserves was the discovery of a momentous national solution, even though the reserves consist of lignite, a lowly ranked form of coal in energy content.
Engro pounced on the opportunity, first forming the Engro Powergen Thar Limited (EPTL), then teaming up in a joint venture with the Sindh government for the mining — a clever move to lock in the political and bureaucratic establishment with its corporate financial plans. According to a publicly available information pack, EPTL initially planned two stages of coal power scaling up from 600 megawatt (MW) to 1.2 gigawatt (GW), the numbers would change a few times over the years.
The selected mining area, called Thar Block-II, is said to have exploitable lignite reserves of 1.57 billion tonnes with the potential to generate five gigawatts power for 50 years. The leased mining area is spread over 95.5km2. Apparently, the project planning was initiated several years ago, around 2010. The promotion material boasts, “Given the large energy deficit and the lack of any sustainable indigenous resources in the country, the Thar coal project presents a tremendous growth opportunity.”
According to a news report (Dawn, July 2017), the National Electric Power Regulatory Authority (Nepra) set an offtake tariff, the all-inclusive buying price (also called the Levelized Cost of Electricity or LCOE in energy industry jargon) for the project’s 30-year electricity output at 7.33 US cents/kWh. The overall project deployment cost is estimated at an average of $1.2 million/MW.
A more recent news update (Dawn, Dec 30, 2017) reports that 660 MW of Thar coal power supply to the national grid is expected by December 2018. The total project investment comes to $1.945 billion, of which $845 million is for the mining. The remaining $1.1 billion divided by 660 MW comes to $1.6 million/MW for the coal power plant commissioning. Another $2.5 billion investment is earmarked for complementary works in the area, bringing the total bill to $4.5 billion. The project is included in the China-Pakistan Economic Corridor programme — another seal of approval. The project managers optimistically mention the prospect of electricity exports to India.
While EPTL and the Sindh government have invested considerable time and financial resources in the protracted Thar project planning, mining and other works to date, a project of this magnitude deserves intense scrutiny at every stage, a check of how it compares to alternative courses of action at each juncture.
Whatever financial spending has happened to date is a “sunk cost”, money that has already been spent and cannot be recovered, whether for good or bad. What matters most is deciding the best path forward, based on what we now know.
To assess the value of coal power, one must understand the nature of the beast. Coal follows the thermal route to electricity generation. There are two basic defining characteristics of thermal power plants: technical and commercial. A thermal power plant initially transforms the chosen fuel ingredient into heat energy that is subsequently turned into electricity by a steam turbine. It is an indirect conversion process that requires copious amounts of freshwater to create steam from the heat energy as an intermediate step.
The other important characteristic is that the plant requires a recurrent supply of the fuel, with an associated variable (operational) cost of production, for electricity generation. The variable cost is driven by volatile financials of the fuel supply — no one really knows how to predict or control fuel prices over the long run, no matter what one might claim.
PLENTY OF CHEAPER ENERGY, HERE AND NOW
Is there really a “lack of any sustainable indigenous resources in the country” to meet our “large energy deficit”?
The 21st century ushered in an alternative system of large-scale electricity generation, challenging the status quo of thermal power plants. This new category is called renewable energy or renewables for short. Abundant natural assets in Pakistan, the renewables of solar photovoltaics (PV) and wind are local resources ideally suited to meet our large energy deficit, without being a major drain on scarce water resources, polluting the air, causing environmental damage or social displacement.
Solar PV is the direct conversion of light into electricity by semiconductor materials, with silicon being the most commonly used semiconductor for the purpose (over 90 percent of the market). Silicon is the second-most abundant element in the Earth’s crust (and the universe for that matter). Wind plants take kinetic energy in atmospheric velocities to drive a mechanical system for electricity generation. The main materials used in wind turbines are glass or carbon fibre-reinforced plastics. Neither solar PV nor wind energy face a potential materials shortage for the foreseeable future.
These renewables do not need any recurrent supply of fuel. The variable cost of fuel supply is zero, for the entire planned duration of the power plant. The power production process does not need the intermediate steps of creating heat energy and then converting it into electricity with the use of freshwater and a steam turbine. The water withdrawal and consumption requirements for operating these renewables, small amounts for routine cleaning, is therefore relatively trivial.
How much solar electricity can be produced from the 95.5 km2 allocated mining area for Thar Block-II? The land usage requirement for ground-mounted solar PV, using standard fixed-tilt arrays, is 1 MW-peak per 12,138 m2. The solar MW-peak capacity needs a capacity factor adjustment for the local operating conditions. Adjusting the 1 MW-peak by a capacity factor of 20 percent, we come to 1 MW per 0.06 km2 (5 x 12,138 m2 = 60,690 m2) i.e. 1,574 MW for 95.5 km2 (95.5 km2 divided by 60,690 m2). The solar power capacity of the mining area alone is well over twice the 660 MW coal power plant.
The block of land can be used again and again for solar PV. The bankable lifetime of a solar PV plant is 25-30 years. However, the solar PV plant can be easily replaced by another after the 25 to 30-year period, with a lower installation cost and electricity output price for each successive installation.
How much solar electricity can be produced from the 95.5 km2 allocated mining area for Thar Block-II? [About] 1,574 MW for 95.5 km2 (95.5 km2 divided by 60,690 m2). The solar power capacity of the mining area alone is well over twice the 660 MW coal power plant.
How would the solar electricity buying price (the project LCOE) compare to that of the 7.33 US cents/kWh set by Nepra for the EPTL coal project?
The electricity buying price for the latest 100 MW-peak extension of the Quaid-e-Azam Solar Park near Bahawalpur, being undertaken by Zorlu Enerji, has been reportedly agreed at 6 US cents/kWh for 25 years — that’s 18 percent cheaper than the Thar coal tariff!
The daily insolation at Thar is about the same as Bahawalpur, an average of nearly 6 kWh/m2 per day (about twice the level of Germany, a global leader in solar per capita). A greater project size possible on the 95.5 km2 of land enables a lower procurement cost, an economies of scale effect, so an even lower tariff than Bahawalpur is possible. Alternatively, the Thar solar project developer can pocket a higher profit than Zorlu Enerji at the same tariff of 6 US cents/kWh.
It should be clear from the above, that solely on the basis of the achievable project financials, renewables are a preferable option to coal for the designated Thar land. It’s better for the potential financiers and owners of a large-scale electricity project on the land, the people of Thar, the electricity infrastructure of Sindh and Pakistan, our national economy, the welfare of our shared planet.
WATER NOT COAL
The absurdity of coal mining and thermal power plants in areas with acute water stress should be self-evident. Mining operations require around 250 litres of freshwater per tonne of coal. The daily diet of coal for a thermal power plant is about 12 tonnes per MW. A typical 500 MW coal power plant then needs another 1,300 million litres of freshwater a day for the electricity generation process, varies by the exact heating and condensing technology. That’s close to three litres of freshwater per day for every inhabitant of Sindh.
Solar electricity can be used to desalinate brackish water deposits into drinking water for the local population. Community-based solar powered desalination projects have been demonstrated to deliver drinking water at a cost of as low as one US cent per litre. Rather than being a drain on dwindling freshwater reserves, a solar project would have the opposite effect.
THE GLOBAL ENERGY TRANSITION