The fog harvester
John Lovell is holding onto a rope, easing himself down a steep drop-off.
“I’ve already fallen off it once!” Lovell yells, looking down a steep canyon called Avalon in Daly City. It’s a gusty place, with planes constantly overhead. Lovell is here to check on his harvest.
“People ask me what I do, and I say, ‘[I] harvest fog,’ they say, ‘Harvest frogs?’” Lovell laughs.
Lovell is a fog harvester. He’s obsessed with the fog, and the water resources that are floating right over our heads. He points at a little white fluffy cloud.
“This one over here, this chunky one right here, that's probably about 100 or 200 elephant weight, probably 80- to 90,000 gallons of water.”
Elephants. That’s how some researchers measure the weight of a cloud. Let’s say the density of a cloud is 500 million grams of water, or 1.1 million pounds, and its volume is about a billion cubic meters. Multiply those numbers together and it starts to get hard to wrap your head around. Therefore, elephants. An elephant can weigh about four tons, so that little puffy cloud that we’re looking at right now is about 100 elephants. That’s a lot of water in the sky; millions of elephants overhead as far as the eye can see. Then, there’s the fog.
“Fog is a lazy cloud, decides not to get up -- heavier water droplets that don't get pulled up by an updraft,” explains Lovell. “It goes over countrysides, coming in from the ocean.”
I follow Lovell down the side of the cliff where we reach a plateau area. We’re at the harvesting site. The design is actually not that complicated: in an area of about 50 feet there are four large rectangular metal panels held up about 10 feet high by a metal stand. On the surface of each panel is a mesh grid angled toward the sea. The fog gets trapped in the mesh as condensation and drips down through plastic tubes into blue containers sitting on the ground.
Lovell points at one of the containers, which is full of water. “Go ahead and pick it up! That's a lot of water, that's 26-and-a-half liters, seven gallons. In a heavy fog event, we got that in six hours. “
Lovell has been coming down here to check these buckets. If his calculations are right, he’s averaging about a gallon of water an hour per panel when there’s heavy fog. He thinks that placing 50 of these panels in a place with frequent heavy fog could yield about 5,000 gallons of water a day.
But the water collected by the fog harvesting mesh isn’t potable. If you drink it, you’ll get sick. Lovell says that’s alright, because there are other important uses for this water.
“Right now we are at agricultural level -- this is for the vineyards and other agricultural endeavors,” he says. “If they have fog on their property this is going to be a way to get water in viable amounts over a long period of time.”
John Lovell wasn’t always a fog harvester. He used to be a carpenter. He says there was a moment a couple of years ago that started him on this path. He saw a TED Talk online, given by architect Michael Pawlyn, about sustainable architectural environments. After hearing that talk, the world’s water issues weighed heavy on Lovell’s mind. He became angry at the lack of attention on a water crisis that affects so many countries around the globe.
“We live on a planet that's 70% water and have 2.5 billion people living on two liters of water a day,” he says. “And for people to say, ‘That’s terrible,’ I say try it. I did.”
So Lovell tried an experiment on himself. For a few days, he attempted to live as many people do around the world, where water is scarce.
But empathy wasn’t enough -- Lovell wanted to find solutions. He heard about a company in Boston doing research on condensation, a place called NBD Nanotechnologies. So he called them up and said he wanted to be involved in some way. With Lovell being in the ideal location for testing fog, the Northern California coast, they asked him to facilitate their first pilot program, even though he’s not a scientist.
“I’m on a learning curve,” Lovell says. “I’ve read a ton of stuff and theres a ton more to read, but being in the field, I'm getting a hands-on experience.”
Lovell asked friends to help build the fog harvesting structures and NBDNanotechnologies agreed to assist with the technology needed to record his data. I met the team from NBD when they flew in from Boston to visit the site.
Deckard Sorensen, the president of NBD, explains, “What we are trying to do is offer an alternative solution that is environmentally friendly and not harsh to the environment around it, but actually takes advantage of what’s naturally ... here in San Francisco, which is the heavy fog you see rolling over the Bay on a daily basis.”
Sorensen started the company in 2013 to research sustainable solutions for the world’s water crisis. Since then, the company has gained the interest of private investors, to the tune of over five million dollars. When I ask Sorenson about the yields they’ve measured from the fog harvest, he says it’s still in a testing phase and he doesn’t want to give me this info yet. But what is clear is that the scientists at NBD think successful fog harvesting could actually help solve the world’s water problems.
Although this is NBD’s first fog harvesting project, this kind of research has been going on since the 1980’s. At least 17 nations have experimented with some type of application to convert fog into water. But so far, fog harvesting has not appeared to be a viable large-scale solution to water shortages. According to some scientists, fog collecting can be helpful for rural areas in underdeveloped countries. But the average water consumption in the developed world is too high for something like fog harvesting to make a dent. Plus, fog is unpredictable. Sometimes you see it, sometimes you don’t.
Some scientists also say fog harvesting would be more successful with more effective materials. NBD has designed a new kind of mesh for their fog panels, one that they believe is creating higher yields. It’s working great on Lovell’s fog harvester.
“We notice no wash-off of our material into the water,” Lovell says. “Whatever the fog is carrying, it goes into the reception container.”
Lovell and the scientists at NBD think that eventually these types of fog-catchers can be used on a much larger scale. Today, there’s no fog in sight. But that doesn’t discourage John Lovell. Though he lives way up the coast in Fort Bragg, Lovell says, “I’m down here all the time. I have to check on it. I can’t abandon it.”