Transformer Elevation for
Hurricane Hardening
TECO engaged Southern Switch to raise and re-set power transformers at two substations serving critical infrastructure in the Tampa Bay area — including facilities tied to MacDill Air Force Base. The work combined heavy-lift crane coordination, reinforced platform installation, and full transformer apparatus testing before the units returned to service.
serving critical loads.
MacDill Air Force Base sits on a narrow peninsula extending into Tampa Bay — one of the more exposed positions in Florida for storm surge. The base hosts major DoD tenant commands and operates around the clock. A flood event that takes out substation transformers is not a maintenance problem; it is a mission readiness problem.
TECO’s broader hardening initiative addressed this by physically elevating transformer units above projected surge levels. The primary location required concrete pad platforms approximately three feet above grade. A second location with lower but real flooding risk received steel I-beam platform sets. Four transformers in total across both sites.
was responsible for.
TECO retained Southern Switch as the field services contractor for the transformer portion of the project. Our scope covered the heavy lift, platform setting, and apparatus testing. TECO’s own crews handled protection and control testing and official commissioning.
- →Coordinated and managed Beyel Brothers crane operations as subcontractor
- →Lifted and set 2 transformers on reinforced concrete platforms (~3 ft elevation) at the primary MacDill-area substation
- →Lifted and set 2 transformers on steel I-beam platforms at a secondary flooding-concern location
- →Performed complete transformer apparatus testing on all four units prior to return to service
- →Provided documented test reports with raw data, instrument calibration records, and findings
- →Protection and control testing and relay verification
- →Platform and structural civil work
- →Official commissioning and return to service authorization
elevated platforms.
Each transformer was disconnected, de-energized, and rigged for lift. Beyel Brothers operated the cranes under Southern Switch coordination. At the primary MacDill-area location, the units were set onto pre-poured reinforced concrete pads approximately three feet above existing grade. The pad height places the transformer base above the storm surge elevation identified in TECO’s hardening study.
At the secondary location, steel I-beams provided the elevation structure — a faster and lower-cost approach where the flood risk was real but the surge projection lower. Both solutions keep the transformer tank, bushings, and control cabinet above standing water that would otherwise reach them in a significant storm event.
return to service.
After each unit was set and reconnected, Southern Switch performed a complete suite of transformer apparatus tests. These establish a post-lift baseline, confirm that the move introduced no damage to the windings, core, or insulation, and satisfy the documentation requirements for a unit returning to service under utility operating procedures.
Megohm readings at 1-minute and 10-minute intervals establish PI and DAR values. Confirms winding-to-ground insulation integrity after the lift and reconnection.
All tap positions tested against nameplate ratio. Verifies winding integrity and that no internal connections shifted during transport and set.
DC resistance measured per phase and compared across phases. Flags loose connections, deteriorated contacts, or winding issues not visible on the exterior.
No-load exciting current measured per phase. Sensitive to core deformation — any core shift during the lift would show here before the unit is energized.
Capacitance and power factor on windings and bushings. The most sensitive indicator of moisture ingress or insulation degradation that may have occurred during de-energized handling.
Fluid samples taken for dielectric strength, moisture content, and dissolved gas analysis. Samples sent to a qualified laboratory for processing and establishes a post-lift oil baseline.
above surge level.
All four transformers passed apparatus testing with results consistent with their pre-lift condition. No insulation anomalies, no winding damage, no core shift detected. TECO completed P&C testing and commissioning, and the units returned to service serving both the primary critical load and the secondary location.
The project reflects an approach to storm resilience that Florida utilities are increasingly adopting — not just restoring infrastructure after a storm, but positioning it to survive one. Elevating a transformer is a fraction of the cost of replacing one, and considerably less than the cost of an extended outage to a critical facility.
We coordinate the full scope — crane subcontractors, platform setting, apparatus testing, and documentation — so TECO’s team can focus on P&C and commissioning. Send us your site and transformer details.