BY ALDETH LEWIN (DAILY NEWS STAFF)
ST. THOMAS - The project to connect the Virgin Islands to Puerto Rico's power grid is one step closer to becoming a reality now that the V.I. Water and Power Authority is moving ahead to conduct an environmental impact study.
A Request for Proposals has gone out seeking a consultant to asses the environmental impact of a proposed power transmission cable connecting Puerto Rico to the Virgin Islands.
The 50-mile cable would connect the Harley power plant on St. Thomas to the Fajardo substation on the east coast of Puerto Rico.
A possible St. Croix interconnection would be from Frederiksted to the Yabucoa substation in southeastern Puerto Rico, a distance of about 80 miles. While technically feasible, the St. Croix connection would be about 340 feet deeper than any existing cable worldwide. It would require additional laboratory testing and likely be much more expensive.
WAPA also is evaluating an interconnection from St. Thomas to the British Virgin Islands, according to officials.
The environmental impact study will include several required studies related to the construction and operation of the cables: a bathymetric study; a benthic study; an archaeological investigation; and a landing-site survey.
The main environmental concern is what impact the cable would have on the ocean floor.
Federal permitting agencies, as well as state permitting agencies in the Virgin Islands and Puerto Rico, will be involved in the environmental review of the project.
The cable landing sites will require coastal zone management approval, WAPA officials said.
"This is the last round of studies. Once we get this back, then we can secure the financing," WAPA Executive Director Hugo Hodge Jr. said Monday.
The study follows two previous technical studies: one on the feasibility of the submarine interconnection and a second to evaluate the highest level of renewable energy - such as solar and wind - that the utility can put onto its grid with and without interconnection to Puerto Rico.
Siemens Power Technologies Inc. conducted the two studies, which were funded through a $200,000 appropriation from the V.I. Legislature and a $475,000 grant from the U.S. Department of Energy.
The report found that upgrades to the territory's system would be needed before the interconnection could be implemented.
Hodge said the utility would enter into a commitment with Puerto Rico to purchase a minimum of 10-20 megawatts, with options to buy more power if needed.
The transmission cable most likely would carry up to 200 megawatts.
Hodge said the plan is to then sell power to the British Virgin Islands (BVI) or other Caribbean islands.
"We plan to sell to BVI and down the chain from there," he said.
Once all the studies have been complete, financing is secured and permits are in place, the project should be done within a year, Hodge said.
"It takes about six to nine months to make the cable and about 60 days to lay the cable," he said.
The WAPA board has included the interconnection to Puerto Rico as a viable option in its Energy Production Action Plan. The plan says interconnection will allow WAPA to integrate more renewable energy production without impacting the stability of the grid; reduce air emissions; reduce overall electric rates and produce fuel savings; allow for more efficient power generation; allow preventive maintenance work to be done on equipment without interrupting service; and reduce the risk of damage or loss of power from hurricanes and other natural disasters or fuel shortages.
Officials hope the interconnection will lead to a Caribbean grid system similar to mainland electrical grids. Such a grid would increase reliability and lower rates, according to WAPA.
WAPA is looking for federal funding and exploring other financing options to pay for the interconnection. WAPA estimates the project would cost between $125 million and $300 million, depending on whether one or both islands are connected; the size of the cable; and other infrastructure upgrades that may be needed to maximize the efficiency of the undersea cable.
Hodge said at least one agency has offered a low-interest loan to complete the project, but all options will be considered.