BL&P mulls over underground cables

by Marlon Madden

The island’s sole power utility company is reporting the benefits of having some of its transmission cables underground, and is looking at the possibility of expanding this network.

Johann Greaves, Director of Operations at the Barbados Light & Power Company (BL&P) Ltd., said while the effects of adverse weather systems on the company’s overhead power lines and poles tend to be more severe, the underground systems have been more resilient.

Following the freak storm on Thursday, June 17, which packed wind speed of up to 40 km per hour and an unusual amount of direct lightning strikes to utility poles, several downed power lines were reported.

Equally, initial damage assessment following the passage of category one Hurricane Elsa on Friday, July 2, indicated that approximately 200 poles and 45 transformers are to be replaced and about 1 km of wires are to be restrung. However, the company is said to have mitigated any adverse damage to its underground cables in both instances.

Speaking during a recent media update, ahead of Hurricane Elsa, Greaves explained that over the years the company’s underground cables have been spared the worst whenever there was bad weather that usually impacts the overhead cables.

“So basically, for the bulk movement of power we have quite a lot of our infrastructure underground already and that has shown its benefit over the years, being able to have the resilience on our network,” he said.

According to the BL&P, its transmission and distribution system consists of just over 150 kilometres of transmission cables and power lines, stretching across roughly 77,000 distribution poles and 18 substations, of which 12 are entirely connected underground with redundant transmission links.

Some of the critical loads fed entirely by underground and directly linked to a power station are larger customers including the Bridgetown Port, the Queen Elizabeth Hospital, the Grantley Adams International Airport, the Belle Pumping station, and the Warrens and Bridgetown areas.

Following a power outage it is easier for those connected to the underground system to be restored with power once it is safe to do so, due to little or no damage, compared to overhead wires that may be torn down.As such, Greaves said the company was examining the possibility of having more of its cables underground.

“We have over the years implemented undergrounding where it made a lot of sense and the security of the network, and we are continuing to evaluate other options for undergrounding, both at the transmission and distribution levels to get power to customers,” he said.

However, he quickly pointed out that having cables underground was not free of challenges. “Undergrounding is something that we are looking at to see how we can underground some more of our systems.  However, the undergrounding comes with another set of challenges – it is a lot more expensive because rather than just planting a pole and stringing a wire, we are talking about excavation, back filling and reinstatement of the ground, that sort of thing,” he said.

“It also comes with the point of when there is a fault. When we can send a crew and look overhead and see the fault and repair it quickly, repair time for underground services are a lot more involved because first of all you have to use special equipment to identify where the fault is [then] you have to get permission to excavate the roadway to effect repairs,” he explained.

marlonmadden@barbadostoday.bb