Buoy, oh buoy: UVic engineers get powered up by ocean waves

Campus News Science

Grey waves crash against a lone buoy off the coast of Vancouver Island. Pale sunlight glitters across the Pacific and stretches far into the distance — a silver blend of sea and sky. A seagull hops atop the buoy’s red surface and bobs along to the ocean’s beat. Another wave slams into the metal. And on the rocky shore of Kaneohe Bay, a cottage light flickers to life: harnessing energy from Vancouver Island’s ocean waves is slowly becoming a reality.

The West Coast Wave Initiative (WCWI) is composed of engineers at UVic who study how to convert an ocean wave’s kinetic energy into a source of electricity. And last October, they received $150 000 from the B.C. government’s Innovative Clean Energy Fund.

That sum will contribute to the creation of a fifth wave measurement buoy, which adds to a fleet of four already on the water. The addition of this fifth buoy will make Vancouver Island one of the largest wave energy sources in the world.

“Having that provincial buy-in is pretty important,” said Dr. Brad Buckham, a mechanical engineer at UVic, and director of the WCWI. “If the province . . . isn’t financially involved, or vested in [the project] at all, it’s not a good indicator at the federal level.”

The measurement buoys stationed along the coast move with the water as their sensors measure Earth’s gravitational pull. Every 12 to 15 seconds, a wave hits one of the buoys. The sensors record how much power a specific wave can harness and then sends the data to UVic.

“Phenomenal cosmic power! Itty bitty living space!” said Buckham, quoting Aladdin. “Our job is to harness that power.”

After 11 years of analyzing the first four buoys, the WCWI team concluded that the waves off of Vancouver Island provide 35 kilowatts of energy per one-metre wave. The team also found that ocean waves change with each season; during summer months, waves only produce 15 kilowatts per metre, whereas in January, the waves provide 70 kilowatts per metre. But even on its calmest day, the Pacific Ocean still provides at least 8 kilowatts of energy per one-metre wave.

Satellite signals transmit the buoys’ data to the WCWI’s computers in UVic’s Engineering Office building. The data includes measurements of sea depth, the shape of the coastline, and strength of ocean waves. With this information, the team determines the best way to create a consistent wave flow in order to meet the electricity demands of Vancouver Island.

“[With the data, we] look at potential siting locations, because obviously not everywhere has equally good waves” said Dr. Helen Bailey, who runs the data analysis process.

AXYS Technologies in Sidney builds the measurement buoys from metal and high-density foam. Since their founding in 1976, AXYS has focused on wave energy resources and hopes to continue adding buoys to the coast. Once finished, AXYS will help the WCWI deploy the fifth buoy into the water.

One group, though, is wary of ocean waves as an energy source. According to the B.C. Marine Conservation Analysis (BCMCA), the buoys’ mooring lines have to be attached to the ocean floor and may disrupt aquatic life. In addition, servicing the buoys requires vessel transport, which burns diesel.

However, Buckham noted that the WCWI values environmental concerns and works closely with the BCMCA. “Yes, the technology is green,” Buckham said. “But there’s going to be an environmental cost.”

The main way in which the WCWI works with the BCMCA is by ensuring future buoy placements aren’t in specific marine-life locations. “We have [someone] doing a sighting study, looking at those areas [with] high fishing areas, or marine protected parks, or whale migratory routes,” said Bailey. “So it’s a matter of finding a location with good wave energy and has the potential [for the buoy] to be sited there.”

Buckham noted that British Columbia already uses renewable energy from hydro dams, so the demand for wave energy isn’t high. He added, however, that the technology wouldn’t be for this generation, but for others to follow, and noted that there will always be a global market for clean energy.

“The development of these ideas, and the trial and error [needs to happen now]” said Buckham. “I might not be around when all this comes to pass, but that doesn’t mean it’s not worthwhile.”