Thiruvananthapuram | As the September heat lingered over Keralam, the state's power grid came under growing strain on Tuesday, with electricity demand surging enough to force partial restrictions during the evening peak.

The prolonged dry spell and warmer-than-usual conditions meant greater reliance on fans, air-conditioners and other cooling appliances in homes and commercial establishments.

This pushed up consumption at a time when the availability of electricity from the power exchange was already under pressure, officials said on Wednesday.

With power unavailable in the required quantity through the exchange and grid frequency falling, partial power restrictions were imposed in Keralam between 6.30 pm on Tuesday and 12.30 am on Wednesday.

The Kerala State Electricity Board (KSEB) had warned that the combination of rising demand and limited availability through the power exchange could make power restrictions necessary.

The pressure was not limited to Keralam. Electricity demand had risen across the country, resulting in a significant decline in the availability of power through the power exchange.

A notification from the Grid Controller of India said the country was still facing a power availability shortage of around 12,000 MW.

There was also an unexpected reduction in the availability of electricity from central generating stations, adding to the pressure on the state power system, officials said.

In Keralam, peak-time demand in recent days had risen by around 800 to 900 MW compared to the demand normally recorded during September in previous years.

With the rains staying away, demand was expected to rise further by a similar margin, officials said.

The impact of the unusual heat was visible in the temperature readings released by the India Meteorological Department (IMD) on Tuesday evening.

Punalur recorded the state's highest maximum temperature at 35.2 degrees Celsius, which was 3.3 degrees above normal. Kottayam was even further above its normal temperature, recording 34.6 degrees Celsius - - 3.8 degrees above normal, the highest departure among the stations monitored.

CIAL Kochi recorded 34 degrees Celsius, while Thiruvananthapuram city recorded 33.6 degrees. Kozhikode recorded 33.5 degrees, and Vellanikkara and Palakkad recorded 33.4 degrees each.

Temperatures were also above normal at several other stations including southern Thiruvananthapuram and northern Kannur.

The warmer conditions, coming at a time when the monsoon rains had weakened or stayed away, added to the demand for electricity during peak hours.

For Keralam, the immediate pressure eased after the restrictions, but the combination of above-normal temperatures, weak rainfall and tight power availability remained a concern as the state headed into another day of high electricity demand