As the human population of the Earth increases by 83 million per year, the necessity of switching to clean, renewable sources of energy becomes ever more urgent. With fresh water arguably the most vital resource of all, desalination of seawater is necessary to meet growing demand.
Given that desalination is an energy-intensive process, how can we produce fresh water with inexpensive, clean, renewable energy?
Wave-Powered Water Pumps
Atmocean is a company that is developing a clean-energy system to pump seawater into desalination plants in the cleanest way possible: by harnessing the energy of ocean waves.
Atmocean’s Wave Rider system utilizes a buoy that rises and falls with the passage of waves. As described in Popular Mechanics, “At the base of the buoy is an integrated cylinder attached to a piston rod. It begins to rise and fall with the waves, collecting and pushing water all the way back to shore through a 10-inch wide pressurized hose—all without an external energy source.”
Christopher White, Chief Operating Officer of Atmocean, says: “With pressurized seawater arriving on shore, we can input it into a desalination facility without the need for grid-tied electricity or costly fossil fuels to run generators.”
The cost of pumping water into the plants is the most energy-intensive part of the desalination process. Wave-driven water pumps could provide an expensive source of clean energy for drinking water.
The Wave Rider Potential
According to the Bureau of Ocean Energy Management, the potential for tidal and wave power is on average a thousand times greater than for wind power. The US continental shelf alone can provide 1170 terawatt-hours of wave energy per year, which is equal to 3.2 terawatt-hours per day.
What is this in terms of drinking water? According to AMTA, the desalination plant in Perth, Australia produces a thousand gallons of water for every 1.3 kilowatt-hours of energy, or enough water for ten people at US consumption levels. In other words, 3.2 terawatts per day is enough energy to produce fresh water for more than 25 billion people — three times the current population of the planet.
With all the coastlines of the world taken into account, Atmocean’s Wave Rider concept means that low-tech water pumps could provide more than enough clean energy to power global desalination needs for an increasingly thirsty world, for generations to come.