by Rose George
Except it didn’t work. By 1980, half of the shiny new digesters were broken. The problem was humans, technology, and the fraught relationship between them. These early digesters were made of brick and often leaked. Also, the Chinese academic J. X. Hong, writing in China Biogas in 1993, estimated that a digester needs 66 pounds of feces daily to function properly, along with 13 gallons of urine and water. This works out to the produce of twelve people, an unlikely family size in a country where couples were permitted one child only. Farmers with fewer pigs added rice stalks to boost the digestion volume, and the stalks caused clogging.
There was little training in maintenance and no network of repair centers to step into the knowledge breach. When the units broke, they stayed broken. So the biogas digesters, despite their potential benefits, were abandoned, and China’s farmers went back to their smelly mao kun—a hole-in-the-ground latrine—and to spreading the hole’s contents on the fields, crude and teeming with pathogens.
Once again, farmers’ wives set off each day to cut wood from the forests. Deforestation reached a scale that alarmed even the far-off government in Beijing. Thoughts turned to the broken digesters, and to how they could be improved. At the same time, other thoughts were occupied by the phosphorus question. Human excrement contains nitrogen and phosphorus, which is plant food. Plant food is worth money. This economic fact oiled the wheels of the night-soil collection industry enough to make its operators powerful. By the late nineteenth century, the leaders of the night-soil trade had been given the ironic title of fenfa, or shit lords. The nickname was derived from junfa (warlords) and neither were to be messed with. In 1925, when Beijing police told the fenfa to move their drying yards—where their product was aired, producing awful odors—they only had to go on strike for three days before public disapproval forced the police to back down.
In 1930s Shanghai, the place dedicated to the loading of night soil onto barges had acquired the name Golden Wharf. This was not ironic but a genuine appreciation of the value of the stinking cargo it carried away to China’s farmers. A Shanghai gangster’s moll ran the wharf, and a mighty business empire. Her real name was Sister Ah Gui, but she was known to all as Fen Huang Hou, or Shit Queen. Whether she objected to her nickname is unknown, but records show that she made a fortune from operating hundreds of night-soil carts. Her profits were $10,000–$12,000 a month.
By the 1940s, when Shanghai had glamour, electricity, and telephones, night-stools (wooden buckets used as indoor latrines) could still be seen lined up in alleys of an early morning. Night-soil collectors still drove their wooden carts through the streets, always courteously informing housewives who might have overslept, “Leaving! Won’t be back!” before they left and didn’t come back. The night-stool was still a standard part of a Chinese bride’s dowry, and “red-dyed eggs were placed inside the night-stool to serve as a symbol or wish for the birth of a child.” By the 1980s, a million Shanghai households still had a night-stool, or “honey bucket.” As late as last year, a New York Times journalist living in Shanghai wrote of her neighbors in her alleyway bringing out their chamber pots to be collected, though the night-soil man’s wooden cart had been replaced by a municipal truck.
But the eggs in the night-stools worked too well. In the vicious circle of night-soil fertilizer production, more people were produced and more people produced more night soil, which produced more crops, which fed more people. Eventually even the land of the fenfa had to resort to artificial fertilizers, which usually contained phosphorus. China again is agriculturally advantaged, having one of the largest phosphate reserves in the world, but even China cannot make the finite infinite. Estimates for when the world’s exploitable phosphate reserves will be exhausted range from sixty years from now to 130, but they will run out sooner if current rates of exploitation continue. Biogas made agricultural, financial, and energy sense.
_______
Perched on the bed in her Xi’an office, Wang Ming Ying tells me that for her, it was all about the trees. In the mid-1990s, she worked in the Propaganda Department of the Women’s Federation. In 1995, she attended the UN women’s conference in Beijing, and it changed her life. “I saw,” she tells me, “how the poverty of women is directly related to the deterioration of the environment.” Poor rural women try to clear more land for crops by cutting down forests. This brought on soil erosion, so more forest was cleared for new crop land. It was a vicious cycle that no one knew how to escape.
Wang set off to northern Shaanxi Province “to see what was going on.” She found hillsides empty of trees and farmers devoid of hope. “I thought that if a woman has education or not, we can do environmental protection together.” She decided to form an organization of women. Mothers, actually. “Mothers are key: they can influence the family.” She named the group the Shaanxi Mothers Environmental Protection Volunteer Association—Shaanxi Mothers for short—and applied to the authorities for registration. They wouldn’t give it.
The group’s name was surprisingly controversial. “They didn’t like the word ‘volunteers.’” Voluntary activity was a problematic concept in China then. Though the word appears in the Chinese national anthem, there was no tradition of volunteering, because public service was always imposed from above. The state controlled everything, and that included excreting habits and public hygiene. Throughout the 1950s, for example, the Chinese government tried several times to eradicate a plague of schistosomiasis, an infection of a parasitic worm found in dirty rice-paddy water (it is also known as bilharzia or, in Chinese, “blood-sucking worm disease”). Shepherd boys, according to a report, “were mobilized to pick up stray excreta.” Elsewhere, there were campaigns such as this one in Tientsin: “Street cadres, together with the chief of the local agricultural producers’ co-operative, members of the residents’ committee, and the farm officer in charge of fertilizer accumulation were asked to adopt the sanitation methods used in model villages. Mass meetings were held in the village, and methods of garbage and excreta disposal, treatment of polluted water, cleaning of pigpens, sealing of manure pits, etc, were demonstrated. Finally, wholehearted participation of the entire village was achieved, and the problem of sanitation was solved.” Simple.
Wang persisted in wanting to be a true volunteer. “For the longest time, everything we did was under command. Now we wanted to do something not because someone was paying us or ordering us but because of our own initiative.”
After a few years of environmental work—there was, for example, a lot of litter collection—Shaanxi Mothers were shown a video of biogas technology. They liked it, and decided to try it out with two test families in northern Shaanxi. The families lived in a village that had a fate typical to the area. Thirty years earlier, its population consisted of four families, and the village was surrounded by trees. By the time Shaanxi Mothers arrived, there were thirty-four families and the forest was almost gone. “Their way of surviving was wrong,” says Wang. “They were cutting more wood for fuel but cutting down their livelihood.”
Biogas was an ideal solution. But when the Mothers arrived for a follow-up survey, neither digester was being used. They couldn’t understand it. “Everybody was so hostile. But biogas was such a good concept!”
The answer lay in the interaction of humans and technology. For any technology to succeed, everyone—especially the crucial early adopters—must fully understand how to operate it. Something had gone wrong with the education process. For months on end, no one in the village would explain why they didn’t want biogas. Then one day Wang was talking to Qiao Liu Ye, the mother in one test family, when Qiao mentioned, almost casually, that her young son had drowned in the digester. Wang was horrified. The family had left the lid off, and their toddler son Peng had wandered up to the hole and fallen in. Whether the tragedy arose from poor instruction or poor comprehension of the instruction was unclear. But Wang learned a lesson. You can’t install technology (the hardware) without ensuring the human element (the software) is also operational. Follow-u
p is essential. Shaanxi Mothers set about soothing the trauma of young Peng’s death by the simple method of talking, a lot. It took months, but it worked.
Ten years on, Shaanxi Mothers have installed 1,294 digesters in twenty-six villages. They have won prizes and funding, though never enough. The money subsidizes a third of the cost of a digester, with the householder and the government making up the rest. Wang estimates that for every new biogas digester installed, 1.2 ton of firewood—three trees—will be spared.
Wang unrolls some large hand-painted posters that are used to instruct villagers how to operate their digesters. The advice runs from the obvious (keep the lid on and small children away; don’t have your lamp too close to the ceiling; don’t install the stove in your bedroom) to the more complicated (stir the slurry periodically to add oxygen to the mix, which feeds hungry microorganisms and helps break down the organic matter). Every so often, mix in some animal dung, which adds more valuable bacteria. Sit back and wait for the benefits. They are many. The excrement is safely contained in the digester, so “the pigs and sheep don’t stink like they used to,” says Wang. The fly population—significant, with all those pigs—is reduced by 64 percent, on average. Most important for the Mothers’ target population, the backbreaking job of chopping firewood has been cut down. Women now have an unusual thing called free time.
The journey to Da Li is long. It goes along roads that are so new they’re not on the map and roads so bad they are flattened rocks with aspirations to being a thoroughfare. After several hours of bone-rattling driving, we arrive in northwest Shaanxi Province, to a village of apples. There are boxes of apples everywhere; being loaded onto trucks; stacked on street corners. Later, I see the same brand for sale in Hong Kong. This is apple country. What the buyers of apples probably don’t know is that this is apples fertilized with human excreta country.
For once, I have not planned well for bathroom breaks. This is unusual, because any woman who travels in India, China, or a country relatively devoid of public toilets learns two things: go before you go and always wear a skirt, the better for squatting. I am wearing a skirt, but this is a busy village, and I won’t use a public roadside. By the time we reach the meeting room in the village council offices, I am desperate.
“The toilet? Yes, we have a toilet,” says one of our hosts, a friendly woman wearing an enormous sun visor on a dull day. She leads me outside, along the street, over some roadworks and to the only public toilet in town. There are four stalls—if holes in the ground separated by bricks count as stalls—no doors and many maggots. I can be composed about travel trials, but this makes me furious. The roadside would have been cleaner. It is unfit for humans, yet better than the facilities that most humans have.
In the meeting room, there is a delegation of half a dozen villagers. We have been sent by Wang Ming Ying, who is a hero here, and all due courtesy is being extended. A blackboard bears the phrase “We wholeheartedly welcome the advice and arrival of our superior leaders,” and bowls of apples and grapes have been thoughtfully set out on the table. They have been fertilized with biogas slurry, the village leader tells me with pride. Look, he says, how juicy the apples are. They are better now that we use biogas. The skin is thinner and the juice is sweeter. Even rice is better. Rice cooked with biogas is chewier and less likely to stick.
The sun visor woman reads from a sheet of statistics about the wonders that biogas has brought to the village: 1,506 people, 368 households, 790 women, 378 working women, 104 digesters. She says that biogas digesters have reduced three things: “Chemical fertilizer, agricultural insecticides, and women’s household labor. There have been three changes. Human and national excreta is now turned into treasure. Households are much cleaner. Neighbors have a better relationship.”
Also, farmers’ incomes have increased. Annually, they save 1,400 yuan ($200) on fertilizer, fuel, and the medicines they would otherwise have to buy for the constant diarrhea and stomach illnesses caused by filthy latrines. She moves from diarrhea to energy. You save two canisters of cooking gas per year, worth 120 yuan ($20). Using biogas for lighting saves another 40 yuan ($5) on energy bills. All in all, she concludes, the village has increased its income by 300,000 yuan ($43,000) a year. “The village,” she concludes firmly, “is happier and wealthier.”
The Shaanxi Mothers arrived in Da Li in 2003. “Everyone here knows Wang Ming Ying,” says the village leader, a jolly man called Zhou. “She comes every month to do checking and follow-up. Everyone loves her.” Next to the meeting table is a loom, because the Shaanxi Mothers didn’t only bring biogas. “They came to liberate women,” says the leader. “Now they have time to do weaving, to earn a bit more money.”
Mr. Zhou speaks in a strong Shaanxi dialect that the translator finds tricky, and has a farmer’s tan and neglected teeth. He was the first villager to install a digester, though it was part of a government biogas campaign that started before the Shaanxi Mothers arrived. He says it wasn’t a difficult decision to get one. “I have a lot of pigs and they create a lot of excrement.”
He doesn’t mention human manure until I ask. “That was also a problem. Before, we would cover our shit in mud in a hole at the back of the house. When we needed it on the fields, we’d bring it over. But sometimes children would play with it. They might destroy the pile and scatter it around the courtyard.” Such a hole is called a mao kun, meaning “straw hole.” “It’s not a hole made of straw. Mao is wild grass, unwanted grass. So mao kun is a hole that no one wants. It is something completely undesirable.” Villagers regularly had worm infections, but they thought that they were stuck with it. They thought they couldn’t afford anything else.
Studies show that people with no latrine or a poor latrine regularly say cost is the biggest obstacle to improving their sanitation, even though a decent latrine pays its way in health and economic benefits. In fact, though the Da Li villagers were dissatisfied, it wasn’t enough to spur them to change. They carried on with the mao kun, even in the awful bitter winters of northern Shaanxi, when the ground freezes and the temperatures reach 12 degrees F.
In Da Li, as in countless other villages, things began to change when the city came back to the country. One hundred twenty-six villagers had left to work in the city over the previous three years. They got used to different standards of living. “Young people were coming home and complaining about the mao kun,” says Zhou. “They didn’t want to use it anymore. They couldn’t deal with it.” They demanded better facilities for their visits home. The women of Da Li proved to be powerful allies. The reason why becomes obvious when Zhou leads me to his house and into the kitchen, past the cartful of apples in the driveway. Here, his wife gives me a demonstration of how she used to live and breathe. She kneels in front of her cast-iron oven, pretending to feed it with kindling and rice stalks, and mimes how she used to cough and how her eyes would water. The ovens are still used to bake bread, but otherwise the two-ring biogas burner is enough for three meals a day in summer and two in winter.
Mrs. Zhou’s savior lies underground. She shows me the square of concrete it lies beneath, and the cleanish latrine behind a curtain next to the pigsty, so that pig and human excrement can be easily sluiced into the digester. Mrs. Zhou uses the time she once spent cooking to work more in the fields. Other biogas families have diversified. In one house nearby, in a small courtyard behind a gorgeous wooden carved door, a Mrs. Yang sits weaving at a loom as if she’s done it for centuries. But she began only a year ago, when the Shaanxi Mothers introduced a new way to fill the hours no longer spent choking on fumes by an oven.
Biogas is not perfect. As the tragedy of Peng showed, digesters can fail because of mechanics and human error. Also, there is little agreement on how safe the slurry actually is. Opinions vary as to whether a four-week digestion process, for example, kills all pathogens. Ascaris eggs, which grow into long and revolting worms, are exceptionally hardy. (They are also still unvanquished, though humanity has been dealing with them forever: ascar
is have been detected in fossilized Peruvian dung dating from 2277 BCE.) Swedish academic Mathias Gustavsson, a fan of biogas—he refers to it as a “solution in search of its problem”—writes that “there is no such thing as a total removal of all parasites due to an anaerobic process.” But a biogas digester has to be better than a bucket.
There are other quibbles. Biogas lamps get very hot and are a fire risk if they’re suspended too close to the ceiling. The Rural Energy officials of Mian Zhu tell their customers to light a match and wave it around before they light the gas, because if there’s more than 5 percent methane in the air they might get dizzy.
Also, the impressive numbers handed out by the Institute of Biogas should be taken with circumspection. Jiang Ping Zhao, a senior energy specialist with the World Bank in Beijing, believes that, technologically, biogas has evolved far enough to be easy to use. The days are past when state officials would install a digester, then be nowhere to be found when it broke down. But the numbers give pause. Chinese government targets project that 80 million digesters will be in place by 2020. They will produce 40 million cubic meters of gas. But Jiang thinks this is odd. “They don’t have meters on the digesters I’ve seen, so where are the figures coming from?”
