The sun and the water often seem to work at cross-purposes. The heat radiating from the sun dries up water and causes it to evaporate. And dousing yourself with water is a surefire way to beat the sun’s often-oppressive heat. But in some circumstances, the two vital elements can work in tandem—as a project recently unveiled in Anguilla reveals.
Anguilla is an arid, flat Caribbean island surrounded on all sides by seawater. As such, it would seem to be inhospitable turf for a high-end spa and golf resort like the Cuisinart, located on the island’s picturesque Rendezvous Bay. Running Cuisinart, with its thirsty greens, multiple pools, spa treatment salons, 100 guest rooms, and hydroponic farm, is a water-intensive endeavor.
But rather than pipe in freshwater from abroad, or dig deep into the earth, Cuisinart several years ago decided to work with the material at hand—seawater. A reverse osmosis plant on an adjacent plot of land desalinates and purifies up to 1.25 million gallons of water daily.
Reverse osmosis is an energy intensive effort. Water has to be pushed through a semipermeable membrane that blocks the salt and other impurities from going through. Creating the pressure necessary to make that happens requires a large amount of energy.
And, as is the case on many isolated islands, the electricity required to run such a plant can be expensive. Anguilla lacks the supplies of fuels—coal, natural gas, oil—that power industrial-scale electricity plants, as well as the infrastructure. Indeed, until 1975, only a small portion of the island had even had access to electricity. In 2012, the peak demand of Anglec, the Anguilla Electricity Company, Ltd., was about 13.6 megawatts. And most of it was generated by burning fuel oil.
Given the size of the island’s electric system, a single large user like the Cuisinart resort could often poses challenges. In addition, high-end hotels can ill afford to be without reliable supplies of electricity—even for just a few years.
So Cuisinart took the next step. It decided to build its own power plant to run the desalination facility. And for that, it turned to the one resource it has in abundance—aside from seawater. The sun.
Cuisinart hired Inoveatus Solar, a firm based in the distinctly non-tropical climate of South Bend, Indiana, to build a large field of solar panels. Arrayed over four acres, the 3,500 panels have a combined generation capacity of one megawatt.
In effect, then, the resort is harnessing the power of the sun to turn seawater into a nourishing resource—for people and plants.
This isn’t the only arid place in which sun, sand, and sea manage this neat trick.
In August 2010, IBM, working together with researchers from King Aziz City for Science and Technology in Saudi Arabia, built experimental solar-powered reverse osmosis plants in the Arabian desert. In Chile, researchers have constructed a small reverse-osmosis demonstration plant in the rural Lluta Valley—also powered by solar panels.
Historically, people have responded to the challenges posed by harsh climates and a paucity of energy resources either by moving, or by adapting their lifestyles to subsist on the bare minimum. But technology today allows companies and people to transform their surroundings by harnessing new sources of energy and applying it to new uses.