Researchers at UCSC have discovered an innovative and totally gross way to revolutionize the production of hydrogen fuel using only sewage and sunlight
It's midnight on the bottom floor of UCSC's Physical Science building. The doors are locked and the motion sensor lights have been dim for hours, but doctoral student Hanyu Wang is still in the lab, compelled by a scientific pursuit so gripping, sleep seems trivial.
After five years, Wang and Yat Li, chemistry professor at UCSC, have successfully engineered a device that converts, literally, what we flush down the toilet into a zero-emission hydrogen fuel that could power a rocket ship. But here's the best part: they hydrogen-based fuel comes from purely natural resources—sunlight and wastewater. In other words, it’s entirely sustainable.
Sustainable, and pretty disgusting—at least, as far as the raw materials go. They’ve made this an unusual and downright odiferous project for Wang, but she does her best to take the funk in stride. Because even though the sewer water smells awful, it contains the cornerstone of the entire operation: a special type of electricity-generating bacteria.
“I like my project a lot,” says Wang. “I really feel like I’m interacting and connecting with the bacteria. I just really enjoy the process.”
Her labmates, however, don’t share the same connection with the electrogenic bacteria that Wang has forged over the years, and sup- port their fellow researcher from a respectable distance.
“The wastewater always smelled weird when I was working with it,” Wang recalls. “You’ve smelled the sewer before, right? It was just like that. People didn’t like to go around my bench, because it was just too smelly.”
But it’s all in the name of science. One day, Wang’s research may hugely impact the way we think about energy production.
With a potential to power cars and industrial machines without harmful emission, hydrogen is an extremely appealing alternative fuel. Though it’s often touted as a fuel of the future, it’s actually been recognized as a viable energy option for more than 50 years—and NASA has safely used it as a power source for missions since its inception in 1958. With its promise of drastically cutting carbon emissions, labs across the country have been working for years to make hydrogen fuel accessible to the masses. So what’s the hold up?
Cost, for one thing—the production of hydrogen fuel has been prohibitively expensive, so far. Which is precisely why the research at Li’s lab stands out: the project runs on sunlight and sewage—two energy sources that are not only cheap but virtually unlimited. Once the device is built, the raw materials cost next to nothing.
“We use what’s naturally available to us—the wastewater and sunlight,” says Wang. “We’re in golden California, so we take advantage of that.”
The project started in 2009, when Li’s wife, Fang Qian, staff scientist at Lawrence Livermore National Laboratory (LLNL), saw potential for a groundbreaking collaboration. Li and Qian both specialize in devices that create hydrogen gas—Li’s using the sun, and Qian’s using bacteria. Led by Li, the UCSC research team has coupled the two devices—a photoelectrochemical cell (PEC) and a microbial fuel cell (MFC)—to make one self-sustaining, water-treating, hydrogen-fuel-producing mega device. We’ll call the hybrid device the PEC-MFC.
The PEC captures sunlight, and uses its energy to kick-start a process known as electrolysis. During electrolysis, water is split into hydrogen and oxygen, and then released as gas. The MFC not only creates hydrogen gas, but also uses electrogenic bacteria to produce electrical energy. While splitting water to make hydrogen seems reasonable, Li recognized that California is in a drought and water regulation is tight, so they tweaked their initial approach.
“The idea is to replace the MFC ‘solution’ [pure water and cultured bacteria] with wastewater that contains these kinds of bacteria naturally,” says Li.
To ensure authenticity, researchers swapped the pure water solution with wastewater directly from the water treatment facility in Livermore, Calif. If you know someone who lives in Livermore, thank them—they may have unknowingly contributed to this research.
Though it may be counterintuitive, Livermore’s dirty water is what makes the clean energy process sustainable. Human wastewater nat- urally contains organic material and electricity-generating bacteria.
Seperately, the PEC and MFC both require an additional energy boost to drive full-fledged hydrogen production, and the added voltage is pricy. But putting them together created a symbiotic solution: the bacteria in the MFC feed off of the organic matter in the wastewater, and during digestion, produce energy in the form of electrons. These electrons are channeled to the PEC, supplying the final electrical nudge needed to reduce protons into hydrogen. In that sense, the MFC acts as a battery, providing energy and enabling the PEC to continuously make hydrogen gas. Essentially, as long as wastewater is available to the bacteria in the MFC, the PEC bubbles out hy- drogen at a fairly constant rate.
On the flip side, as the PEC splits water, the hydrogen is stored in a cylinder and doled out as useful energy for the MFC. Between the chemical fuel-kick from the PEC and the bacteria-generated electrical jolt from the MFC, the hybridized device can take care of itself. It’s a self-perpetuating cycle that works to balance and propagate its counterpart.
But that’s not to say Li and his team didn’t experience their share of unique issues. Occasionally, and for no apparent reason, the PEC- MFC simply stopped working. Wang suspects that the different bacteria in each batch of wastewater may have caused the PEC-MFC to briefly misbehave—some pools may have more electrogenic bacteria than other, especially because the wastewater is allocated for a small-scale setup.
“Each batch of wastewater is different. Maybe the bacteria aren’t happy that day. Or are feeling lazy. They are live cells—they have their temper too,” Wang jokes. “There wasn’t a clear reason why some batches were better than others. So I’d try again, and it’d work.”
With the overall striking success of the PEC-MFC in the lab, Wang and Li have big plans for future projects. Literally. The ultimate goal is to create a large-scale PEC-MFC that harnesses the same stinky raw materials and functions in the same self-perpetuating cycle—the only difference being the sheer quantity of hydrogen gas produced. A PEC-MFC that’s large enough to convert and pump hydrogen directly from a wastewater treatment facility is still just a schematic, but Li and Wang are actively taking steps toward achieving such a mega-device. Hanae Armitage
Local man finds business opportunity and a possible solution in the war on smart meters
When I fifirst sat down with Karl Heiman on the outside deck of his Caffe Pergolesi, I secretly hoped that he was going to tell me about the inescapable perils of radiation; that we should all run for the hills, reject technology and revert to caveman lifestyles.
Instead, the cafe owner spoke deliberately of his invention, which blocks radiation waves from smart meters—and his motivation is as rational as can be: he simply saw a need for a solution and created one.
“I thought, shoot, instead of trying to get the utility companies to stop, why not just shield it?” says Heiman, who serves on the Downtown Commission and Downtown Association Board.
Along with his partner Jack Mc- Sorley, Heiman began making smart meter guards and selling them online a year and a half ago for $129.95 each.
Made from 316 stainless steel—a corrosive resistant type of steel—the guards are essentially Faraday cages, which block radio frequency (RF) waves and contain them to the smart meter.
Radio frequency waves travel radially and are not directional, meaning they can fifilter into the surrounding area, including your home. But the smart meter guards reduces the RF by 98 percent, according to Heiman.
Plenty of daily electronics emit radiation—but when PG&E actively started installing smart meter devices to homes in 2010 in order to track electricity use, the local backlash was quick and furious. The fight between locals and the utility company resulted in arrests, widespread outrage on both sides, and even power being shut off for some residents.
“A lot of people don't want to be exposed [to radiation] and they’re trying to get the utility companies to remove them,” says Heiman “Which is like trying to push a bulldozer uphill.”
The spectrum of conspiracy theories to valid health concerns that surrounds smart meters spans the country, and Heiman isn’t the first to propose a solution.
“You can go on the Internet and there are people who sell, you know, crystal beads that are supposed to protect you from this ... there is a lot of snake oil out there, unfortunately,” says Heiman.
Using his background in semiconductor processing, Heiman’s approach is a much more technical one, relying on the science to create an accessible product.
“We’re really big on data,” he says. “We test the power density before and we test it after and you can see it drops way down as soon as you put [the guard] on.”
But, exactly how much radiation seeps out of smart meters in comparison to microwaves, cell phones, and Wi-Fi routers? It’s a matter of power level and consistency of exposure, says Heiman. Cell phones and microwaves, for instance, only emit only when they are in use (i.e. during a phone call), while smart meters are on continuously.
To Heiman, who says he’s never experienced health effects himself, protecting people’s homes from RF has more to do with peace of mind than combating health concerns. He and his partner don’t delve into the health issues of smart meters because they’re not health experts, he says. But they do know a fair amount about RF.
“RF power drops off fairly rapidly with distance from the source, so if you're really close to a smart meter you're getting pretty high power densities,” says Heiman. “Move away and it will drop an order of magnitude. You get further away and it drops more. The power level that you’re exposed to is a function of how close you are.”
PG&E now offers an option to “opt out” of the smart meter in favor of an analog meter, which does not emit radiation. However, to install the analog machinery costs $75 with an additional $10 charge each month compared to the free smart meter. In comparison, Heiman and McSorley’s smart meter guards are $130 a pop. Judging by the thousands they’ve already sold to households all across the country—with requests from as far as Europe and Australia—the demand is building.
Much of the controversy surrounding smart meters has to do with the fact that there is still little known about how damaging RF really is. A 2011 study of smart meters by the California Council on Science and Technology (CCST) concluded that not enough is known to require further protection. Similarly, in 2012 the World Health Organization sponsored the Interphone Study, which investigated the potential link between cell phone use and cancers. Their conclusions were equally as ambiguous.
“After being in this business for a while I’ve come to realize that there’s a lot of unknowns about this,” said Heiman. “I’m kind of thinking that if I had a child that was sleeping in a bed on the other side of the wall of a smart meter radiating all the time, I’d be a little bit concerned. Who knows what it does to an infant?”
For more information visit www.smartmeterguard.com. Anne-Marie Harrison
SC Fruit Tree Project turns potential waste into wine
What do you do when life gives you more fruit than you can possibly eat? Make wine. Now in its fifth year, the Santa
Cruz Fruit Tree Project is continuing its mission to let no fruit in the county fall to the ground and rot. What began with one man—founder Steve Schnaar—knocking on the doors of houses with overladen fruit trees, is today an ever-growing nonprofifit organization that harvests nature's excess bounty and promotes sustainability through DIY fruit workshops.
Recently, self-taught winemaker Randy West and his wife LaRae opened their sunny Freedom backyard to 18 fruit-wine-curious locals, and taught us the (surprisingly easy) art of turning fruit into wine.
“Last year when we did this, we started tasting wine right away, and things kind of peaked out pretty quickly,” West said at the start of the workshop. So we waited, salivating yet entertained, for the lesson to end, and the tasting to begin.
West has been making wine since the late ’90s; a hobby he admits is “spinning out of control.” What was once his garage is now taken over by wooden barrels of fermenting wine, a giant fruit crusher and press he found on Craigslist, a sleek white bar and racks of sparkling self-labeled bottles.
“The perfect grape—that’s a Pinot Noir for this area—comes out to the right sweetness, and when it ferments, it comes out to the perfect dryness. That's basically what you’re trying to achieve with all these different fruits, but there is always something lacking, so you have to make up for it,” says West.
The variables of fruit wine include sugar and acid—you need both to make a good wine, and unlike most grape wines, you want a little bit of sugar to remain unfermented. Crushing loquats—native to the Far East, and ripening all over town—in a five-pound bucket, and adding enough hot water to make it liquid, West creates the “must.” Leaving the skin on is key to making fruit wine, since it’s loaded with polyphenols and gives each wine its color. He tests the sugar level using a refractom- eter found on eBay, and adds a generous pound of white sugar to bring the sugar reading up to 22 brix. To kill any microbes, he's added sulfur.
“Sulfur is a natural element which kills bacteria, kills anything that's in there— yeast, microbes, whatever,” says West. You can also bring the fruit to just before a boil to achieve the same results. But Schnaar, who likes to experiment with “whatever piles of fruit” come his way (and he is virtually pelted with fruit everywhere he goes), points out that you don’t necessarily need to sanitize your fruit—especially if it hasn’t been harvested off the ground.
The next step is to inoculate the must with saccharomy-ces cerevisiae, sugar fungus, or yeast—sprinkle it on top, and do not stir. The yeast feasts on the sugar and multiplies, creating alcohol as a byproduct, then dies off once it runs out of sugar or the alcohol level reaches about 13 per- cent—whichever happens first. Cover the batch in a fermenter, which can be purchased along with any other equipment at Seven Bridges Coopera- tive on River Street, and punch down the cap two times per day for 10 days.
There are a few other steps you’ll need to take before you can enjoy your batch, but by this time, the tasting had begun, and I recommend doing what West does: “I just google anything I don't know,” he says.
And oh, was it worth the wait. We tasted persimmon wine, the driest of West's varieties, and a sweet-as-cotton-candy Santa Rosa plum wine. Then it was on to cherry, loquat, blackberry, and olallieberry. All of the fruit came from neigh- bors’ harvests, with the olallieberry sourced from Gizdich Ranch, which sells inexpensive bags of frozen “shake”—the berry pieces that fall between the cracks—to local wine and ice cream makers.
West was right—once that sweet wine began to flow, the gathering of strangers became a bubbling gaggle of sudden friends, and we had a party on our hands.
When challenged to name drop his favorite Pinot Noir, West's reply was a refreshing embrace of the true DIY spirit: "Whichever wine I'm having is my favorite. I mean, you wouldn't say which child is your favorite—you just don't do that."
To find out about upcoming SCFTP workshops and harvests, visit fruitcruz.org. Maria Grusauskas
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