Aboitiz-led Davao Light & Power Co. (Davao Light) has been using plant-based ester oil as insulation fluid for its new transformer facilities and as part of its "greening drive" for its distribution network,.

According to the utility firm, it has been allocating P87-million annually for its procurement of at least 1,300 green-leaning transformers to cater to demand growth at its service area. As of end-December last year, Davao Light has been servicing 458,948 customers and its registered peak demand hovered at 459 megawatts.

The firm indicated that since 2015, it has been on its acquisition spree of new transformers as a replacement to older fleets which it already scheduled for decommissioning; and the older transformers were also utilizing mineral as insulation fuel.

As explained, a natural ester is classified as a vegetable oil and it is typically sourced from canola, rapeseed or soybean, hence, it is lyrically regarded as non-toxic and 100-percent biodegradable.

Conversely, mineral oil is from crude petroleum – and while it is generally effective, Davao Light pointed out that one disadvantage is its susceptibility to fire “due to relatively low flashpoint,” and there are also attendant concerns on recycling and disposal.

As noted by Arnel Bersabe, head of Davao Light’s substation and electrical equipment department, “we had difficulties in looking for contractors that can safely dispose of our used transformer oil, which back then was still mineral.”

He added such dilemma prompted the utility firm to shift on its fuel use, and “since it was already widely used in the industry, natural ester was an attractive option to us.”

Bersabe likewise asserted that natural ester “helps prolong the life of transformers and is safer to use than mineral oil because it needs a higher temperature to burn.”

Typically, the average lifespan of distribution transformers stretches for 35 years; but ester oil is seen extending the longevity of such equipment in the power supply chain by roughly 33-percent.

The use of plant-based oil at its facilities, according to Davao Light, is among the anchor program on turning its operations more environmentally friendly. The core initiatives and projects it already employed included the conversion of Davao City’s high pressure sodium (HPS) street lamps to light emitting diode (LED) lights.

For that undertaking in the Davao metropolis, the power firm conveyed that energy consumption of the street lights had been 70-percent lower; and such also resulted in lower maintenance costs – plus, the life cycle of the LED lights are comparatively longer.

On the sphere of digitalization, Davao Light is similarly gaining traction as it already debuted its fully digital substation last year.

Via that digital substation, the power utility company said among the early outcomes it logged had been “enhanced efficiency, reliability and availability of power supply through real-time control and protection operations.”

Davao Light further touted that digital substations “have fewer conventional components that enable space reduction in the total area required for the installation of equipment, allowing for a decrease in substation footprint.”