India’s electricity supply appears much more comfortable than a year ago, when coal and generation shortages led to grid instability and widespread blackouts.
Power consumption has grown significantly, but coal stocks are more than double than last year’s level and grid frequency is staying closer to the target.
Between June and August, total electricity demand met was up by 22 billion kilowatt-hours (6%) compared with the same period in 2021. (https://tmsnrt.rs/3SH6JOd)
The increase was supplied by extra solar generation (+6 billion kWh) and thermal power plants (+16 billion kWh) mostly burning coal.
India’s installed capacity from solar farms and wind turbines had grown 16% by the end of August 2022 compared with August 2021, helping increase the share of output from renewables.
But most of the increase in demand has been met through more intensive and reliable running of coal-fired power stations.
Government policy has encouraged the maximization of domestic coal and prioritized solid fuel movements on the rail network to ensure generators have enough fuel on hand to run when called:
* Domestic coal production increased by 27 million tonnes (17%) between June and August compared with the same period a year earlier.
* The number of loaded coal trains despatched from the mines to power plants averaged 253 per day, up from 214 per day in 2021.
* Coal deliveries to power producers totalled 177 million tonnes between June and August up from 150 million tonnes in 2021.
As a result, power producers have more than nine days of coal inventories compared with just four days at the same point last year.
Higher inventories have meant fewer generator outages, more generation availability, and more firm despatchable capacity.
Increased solar generation has helped meet peak load driven by air-conditioning and refrigeration in the mid-afternoon (incidentally conserving coal stocks).
But more coal-fired generation availability has helped meet high loads in the evening as output from solar panels fades rapidly.
On the nationwide electricity transmission system, frequency has remained close to the target of 50.0 cycles per second (Hertz) – indicating generation and load have been balanced.
Periods of severe under-frequency (below 49.9 Hertz) have been shorter and less common than in April 2022 and October 2021, when big frequency drops were a symptom of generators unable to meet demand.
In recent years, the grid has usually faced its toughest tests in March-April and September-October, when the seasonal rise and fall in cooling demand is not always synchronized with the rise and fall in renewables output and coal stocks.
Electricity consumption as well as hydro, solar and wind output all rise over the summer months and fall in the winter.
But the pre-monsoon spring and post-monsoon autumn shoulder seasons can be challenging if hot weather arrives earlier or persists longer than normal:
* In October 2021, a late blast of hot weather kept air-conditioning higher than usual, while output from renewables was fading, and coal stocks were still low after the monsoon, causing blackouts.
* In April 2022, very hot weather arrived much earlier than normal, when output from solar, wind and hydro sources was still building from their winter lows, stretching the grid again.
At the moment, India’s grid currently appears to be in a more healthy condition because, although coal stocks are low, they are in line with pre-pandemic levels for the time of year.
Current coal stocks should be high enough to keep generators reliably online over the next month until temperatures fall and inventories are rebuilt this winter.
Reliable electricity supplies will support business activity and reduce the need for panicked and expensive purchases of imported coal on the spot market.
Source: Reuters (Editing by Mark Potter)