Energy provider blames high temperatures for increased cable faults

Energy provider Enemalta has blamed high ambient temperatures and higher loads carried by the distribution cables as the cause for latest string of power cuts caused by cable faults.

According to MIA's meteorological office, the highest temperature recorded yesterday at Luqa 38.6°C. On Wednesday, the temperature hit a maximum of 40.7°C.

In a statement, the corporation said that yesterday's high temperatures resulted in the highest electricity demand recorded in 2012. The demand reached 425MW, so far only surpassed in 2007 when the demand reached 434MW.

"It can also be noted that the energy demand yesterday - 8867MWh - went well above the peak load demand day in 2007 - 8696MWh - by almost 200MWh, meaning that even if the power load wasn't as high as 2007, customers used electricity for longer periods," the corporation said.

"Enemalta's current generation capacity stands at 571MW, which is well above the current demand."

According to data provided by Enemalta, the peak power demand has moved from the winter evening to summer noon-early afternoon since 2002.  

Enemalta also said that the latest string of power cuts caused by cable faults can be attributed to the high ambient temperatures and higher loads carried by the distribution cables.

"These cable faults are partially due to the increase in load and also have a tendency to increase at the beginning of summer due to the higher ambient and ground temperatures and higher loads on the cables," it said.

Cable faults are caused by the increased expansion of the cables and the weakening of the insulation as a result of the higher operating temperature.  

Enemalta said that although the cables are designed with such factors in mind, these might fail at weak points.

Enemalta said that out of some 2600 11KV circuits in Malta, only 26 circuits have failed in the past month.

"While four of these faults were directly caused by contractors, many more of them were on circuits which were previously stressed by third party road works contractors," it said.

Referring to yet another power cut in Valletta, Enemalta said this was "another example of extensive road works putting a lot of stress on the cables".

"These kind of faults should stabilise themselves as time goes by since the insulation around the cables would have normalised. Enemalta assures the public that there is enough generating capacity to meet the daily demand," it said.

"Although the power cuts admittedly cause great inconvenience to the localities affected, the demand of electricity lost throughout these outages is considerably small (about 4MW or less) when compared to the peak demand."