WAPA to buy used turbines as new generators face 2028 delay

The V.I. Water and Power Authority plans to purchase five second-hand gas turbines totalling 45 megawatts of generating capacity to address power shortages on St. Thomas and St. Croix while waiting for brand-new equipment that will not be ready until late 2028.

CEO Karl Knight presented the strategy to the Public Services Commission on October 13. Two of the refurbished Mars 90 units, each rated at approximately 9 megawatts, would be installed at the Harley power plant serving St. Thomas and St. John. The remaining three units, also Mars 90 models, would go to St. Croix and enable WAPA to stop paying for leased generation capacity on that island.

Solar Turbines, a subsidiary of Caterpillar, manufactures the Mars 90 turbines. Knight told commissioners that although the authority labels the purchase as temporary, the refurbished equipment will remain part of WAPA's permanent fleet once the new generators arrive. When PSC Chairman David Hughes asked whether the used units would be retired after the factory-new replacements come online, Knight responded: "We are purchasing them outright," and noted they would work alongside the newer equipment.

The current plan represents a change from earlier consideration of three larger Titan 130 generators, each producing roughly 15 megawatts. WAPA decided instead to split capacity across five smaller Mars 90 units distributed between the two islands.

Knight said load testing of the refurbished turbines could begin within weeks, though he did not announce when the units would arrive or begin operating. Under a separate FEMA prudent replacement program, WAPA expects five generation units to reach the territory in 2027.

Factory-fresh generators face a much longer wait. Knight told the commission that late 2028 represented the earliest possible date for a newly manufactured unit to arrive, provided WAPA placed its order with the manufacturer immediately. "The earliest manufacturing time we're seeing is towards the end of 2028," he said.

The decision to source liquefied petroleum gas turbines shaped the timeline for the refurbished purchase. Knight explained that WAPA could have obtained newer temporary units for the Harley plant sooner, but finding LPG-compatible equipment took considerably longer. The incoming Mars 90 units would run more efficiently than the GE gas turbines currently in service. "As you can imagine, LPG generators are not commonplace in the industry. It took us some time to source those," Knight said.

Separately, WAPA has acquired four standby diesel generators rated at 2.5 megawatts each for St. John, adding 10 megawatts total. Knight attributed that choice to the need for speed, whereas the Harley acquisition reflected the authority's strategy around fuel type.