Decommission oil-filled cables without digging them up.
Oil-filled cables that have carried power for decades still hold large volumes of dielectric insulating oil in their paper matrix — a standing risk to soil and groundwater once the cable is out of service. The ODB System removes that oil biologically, in place, by repeatedly injecting bacteria selected specifically to feed on dielectric oil.
Purging never empties the cable.
Decommissioned oil cables must be secured against leaks — insulating oil is hazardous to soil and groundwater. Historically the only answer was excavation: costly, slow, and near-impossible to plan through urban traffic and private landownership.
Purging alone cannot clean a cable completely. The ODB System removes what remains, biologically, with the cable left in the ground.
Five stages, one biology.
Every ODB deployment follows the same sequence, calibrated to the cable's voltage class, oil chemistry and length. Repeat injections continue until verification sampling confirms the target removal efficiency.
01Oil sampling
Oil is drawn from the cable and profiled for hydrocarbon ranges and contaminants — including PCB screening — to define the treatment plan.
02Bacteria design
Cultures are selected and grown against your cable's specific oil chemistry, then formulated with a matching biostimulation nutrient package.
03Hardware prep
A containerised treatment plant is delivered and commissioned — pumps, tanks, separators and monitoring in one unit.
04Cable connection
The plant is connected to existing access points and the bacterial solution circulates through the cable's oil channel over repeated cycles.
05Completion
Verification sampling and cored sections confirm removal efficiency and produce the documentation needed before the cable is left in place or removed.
A container at each end. Nothing dug up in between.
Treatment plant is installed at the existing terminations at both ends of the circuit. The bacterial solution circulates through all three phases; a separator splits recovered oil waste — measurable by the client — from the solution returned to the cable. The cable itself stays in the ground for the full treatment window.
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Documented on live grid infrastructure — not just in the lab.
National Grid — decommissioning oil-filled cables in situ in London.
Over 98,6% oil removal within 16 weeks. No excavation. No civil works. Cables left safely in the ground.
Statnett — decommissioning of high-voltage cable beneath the streets of Oslo.
9.4 km of cable from 1956 and 1977 left in the ground under central Oslo — the first deployment of the method in Norway.
ODB System, answered.
16 weeks on average from first injection to final verification sampling.