Stories - David South Consulting

Entries in carbon monoxide (2)

Friday

Jun192015

Two-stroke Engine Pollution Solution

Friday, June 19, 2015 at 8:41AM

Cities across the South choke on the pollution made by the small two-stroke engines (http://www.howstuffworks.com/two-stroke.htm) powering motor scooters, motorcycles, auto rickshaws, tuk-tuks and other vehicles. People choose these vehicles to get around because they are cheap, powerful and easy to fix. But the environment – and human health – suffers as a result. And as cities balloon and populations grow, the number of journeys and two-stroke engines grows with it.

In large cities across Asia, 1 million three-wheeled auto-rickshaws form an important means of daily transportation, and a source of income for their drivers. And the Asian Development Bank estimates there are over 100 million vehicles using two-stroke engines in Southeast Asia. But these vehicles cause serious air pollution and emissions of carbon dioxide (CO2), which contributes to global warming.

Because two-stroke engines burn an oil-gasoline mixture, they also emit more smoke, carbon monoxide, hydrocarbons and particulate matter than the gas-only, four-stroke engines found in newer vehicles.

In the Philippines, auto rickshaw drivers are pioneering specially adapted two-stroke engines that reduce particulate emissions by 70 percent and carbon dioxide emissions by 76 percent.

Tim Bauer, the 31-year-old American mechanical engineer who developed the technology, said auto rickshaws “play an essential role in the social and economic fabric. But their impact on public health is disastrous.”

Motorized tricycles produce an astonishing amount of pollution: each one is equivalent to 50 cars. In Bangkok, Thailand, two-stroke engines contribute 47 percent of pollution particulates in the air.

The World Health Organization (www.who.org) ranks urban outdoor air pollution as the 13th greatest contributor to disease burden and death worldwide. It has been estimated that the air pollution leads to the deaths of more than half a million people a year. About two-thirds of the residents of Delhi and Calcutta suffer from respiratory symptoms such as common cold and dry and wet cough, much of this caused by two-stroke engine emissions.

Two-stroke engines are highly inefficient users of fuel: up to 40 percent of the fuel and oil goes out of the exhaust pipe unburned. This exhaust is packed with oxides of carbon, nitrogen, sulphur, hydrocarbons and fine dust – all toxic contributors to air pollution.

But the attraction of these engines remains strong. “They are powerful, simple, reliable and robust,” said Bauer, “and spare parts are easy to find. They also have a long lifetime.”

Bauer faced some strict constraints in developing the technology.

“It had to substantially reduce emissions without impairing the engine’s performance. It had to be installed without machining the engine crankcase, and with only a basic tool set. Of course, it also had to be affordable for Filipino drivers.”

Using off-the-shelf components, Bauer developed a kit that turns two-stroke engines into fuel-injection machines. This adjustment reduced particulate emissions by 70 percent and carbon dioxide emissions by 76 percent. He now sells the kits through Envirofit, a non-profit organization (http://www.envirofit.org/). It has been pilot tested at two Filipino holiday resorts, Vigan and Puerto Princesa.

Auto-rickshaw drivers tend to be poor and earn on average US $3 to US $4 a day. The cost of fitting vehicles with Bauer’s new technology is met by microcredit.

“Drivers earn money daily, so it’s easy for them to pay back their loan, and 90 percent of them do it in less than a year,” he said. Over 260 taxi drivers have already installed the new kit.

“These drivers are at the base of the economic pyramid and these tricycles are a testament to their ingenuity and work ethic. At the end of the day, we can improve their lives with a cylinder head, a few brackets and, of course, hard work.”

Bauer pioneered his solution while working on fuel injection in snowmobiles at the Engines and Energy Conservation Lab at Colorado State University. He started to market the solution in Asia in 2004. Bauer has won a Rolex Award for Enterprise to pay for the distribution of the kits throughout Asia.

There is, of course, another solution: an outright ban or measures to push the vehicles off the road. In the Philippines’ San Fernando City, economic incentives were what drove the transition from two-stroke to four-stroke (less polluting) tricycles. In 2001, three-quarters of the city’s 1,600 registered tricycles ran on two-stroke engines. But after a city council mandate to totally phase out the vehicles by 2004, and offers of interest-free loans for down-payments on four-stroke models, more than 400 four-stroke tricycles had replaced the older two-stroke models.

When Bangkok toughened up vehicle inspections and emissions standards in 2000, two-wheelers made up over 96 percent of the city’s traffic. But by March 2004, they made up only 40 percent, according to Supat Wangwongwatana, deputy director general of Thailand’s Pollution Control Department.

By David South, Development Challenges, South-South Solutions

Published: December 2008

Read more about the impact of air pollution on human health in Beth Gardiner's Choked: The Age of Air Pollution and the Fight for a Cleaner Future (Granta, 2019).

Beth Gardiner shows off the first galley proof of Choked on Twitter.

Development Challenges, South-South Solutions was launched as an e-newsletter in 2006 by UNDP's South-South Cooperation Unit (now the United Nations Office for South-South Cooperation) based in New York, USA. It led on profiling the rise of the global South as an economic powerhouse and was one of the first regular publications to champion the global South's innovators, entrepreneurs, and pioneers. It tracked the key trends that are now so profoundly reshaping how development is seen and done. This includes the rapid take-up of mobile phones and information technology in the global South (as profiled in the first issue of magazine Southern Innovator), the move to becoming a majority urban world, a growing global innovator culture, and the plethora of solutions being developed in the global South to tackle its problems and improve living conditions and boost human development. The success of the e-newsletter led to the launch of the magazine Southern Innovator.

Follow @SouthSouth1

Google Books: https://books.google.co.uk/books?id=YtEgTdyZioUC&dq=development+challenges+december+2008&source=gbs_navlinks_s

Slideshare: http://www.slideshare.net/DavidSouth1/development-challengessouthsouthsolutionsdecember2008issue

Southern Innovator Issue 1: https://books.google.co.uk/books?id=Q1O54YSE2BgC&dq=southern+innovator&source=gbs_navlinks_s

Southern Innovator Issue 2: https://books.google.co.uk/books?id=Ty0N969dcssC&dq=southern+innovator&source=gbs_navlinks_s

Southern Innovator Issue 3: https://books.google.co.uk/books?id=AQNt4YmhZagC&dq=southern+innovator&source=gbs_navlinks_s

Southern Innovator Issue 4: https://books.google.co.uk/books?id=9T_n2tA7l4EC&dq=southern+innovator&source=gbs_navlinks_s

Southern Innovator Issue 5: https://books.google.co.uk/books?id=6ILdAgAAQBAJ&dq=southern+innovator&source=gbs_navlinks_s

Creative Commons License
This work is licensed under a
Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 License.

David South |

Innovative Stoves to Help the Poor

Friday, June 19, 2015 at 7:07AM

Half of the world’s population cook with a fuel-burning stove, and this figure rises to 80 per cent of households in rural areas in developing countries. Typical fuels burned include wood, coal, crop leftovers and animal dung. The indoor pollution from smoke and carbon monoxide is a top health hazard in the developing world, ranking just behind dirty water, poor sanitation and malnutrition. The World Health Organization (WHO) estimates that 1.6 million people die each year as a result of toxic indoor air.

A landmark five-year study comparing Guatemalans cooking on open fires, to those using improved stoves, has brought more evidence forward of the damage done by indoor air pollution: “It’s been shown that children living in houses using open fires with solid fuels will have more pneumonia than children living in houses that are using cleaner fuels,” said Dr. Kirk R. Smith, an environmental health scientist at the University of California, Berkeley.

The research, combined with studies in Asia, suggests additional health problems from indoor air pollution, including higher frequency of cataracts, partial blindness, tuberculosis, low birth weights and high blood pressure. The researchers found that cleaner stoves had larger effects than reducing salt in the diet or lowering blood pressure in women, with the results published last July in Environmental Health Perspectives.

But Southern innovators are finding practical ways to curb pollution from indoor cooking and the burning of trash in slums.

In Yunnan Province, China, entrepreneur Hao Zheng Yi’s Yunnan Zhenghong Environmental Protection Co. has been selling clean-burning stoves to rural farmers. One fifth of rural China has no electricity (UN), and 80 per cent rural dwellers burn wood or straw in ovens for heating and cooking. This creates heavy indoor air pollution, damaging health.

The so-called Efficient Gasification Burning system combines traditional fuel and natural gas: a hybrid that helps low-income households to affordably use the stove and not pollute their indoor air.

The stoves are sold for a profit in Yunnan Province, and so far 50,000 have been sold. Because the ovens are sold for a profit, Zhenghong had to consult extensively with the farmers in the design phase to make sure the ovens meet their needs.

The result has been that Zhenghong ovens run for five to eight years using the same amount of wood and hay a conventional oven burns in one year.

Another source of air pollution is burning trash in slums. The lack of formal trash removal services in slums has two bad consequences: one is the pollution and poison from rotting rubbish leaching into the soil and water table; the other is ad-hoc burning of the trash to get rid of it, which pollutes the air with a toxic, acrid stench. In Nairobi’s Kibera slum – the second biggest in Africa – over 60 per cent of the city’s residents live in the slum, and are bypassed by garage collection services. Garbage is piled up along the muddy roads and paths, or hangs in the trees.

The Kenyan NGO Umande Trust, which specialises in water and sanitation projects, has developed a home-grown method to burn trash and avoid having to turn to very expensive and complicated incinerators from Europe. The sheer quantity of trash that needs to be burned in the slum means smaller solutions will not be able to handle the problem.

Its “community cooker” re-uses garbage from the community as fuel for a boiler and oven attached to it. The heat generated by burning the rubbish provides hot water and cooking facilities – and also jobs for unemployed youths who collect the rubbish and stock the incinerator. It was developed by a Kenyan architect, and it is hoped the “community cooker” will be taken up across Africa.

The community cooker’s inventor, Kenyan architect Jim Archer, took eight years to design and build it: “My thinking was how do we get rid of the rubbish and …how can we induce people to pick it up. Then I thought, well if we can convert it to heat on which people can cook…” he told Australia’s ABC News.

Similar industrial scale trash incinerators can cost between US $50 million to US $280 million (World Bank) – “…when applying waste incineration, the economic risk of project failure is high…”. The community cooker on the other hand, will sell for US $10,000.

The idea was to create an incinerator that was simple to use and repair: something that the commercially available, computer-controlled incinerators were not able to do. As the cooker gets up to speed, it will be able to burn 60 per cent of the slum’s trash.

Local youth go house-to-house collecting trash. They get money from the slum residents for this. Rubbish is then exchanged for cooking time or hot water for washing.

“The trash has started to help us a bit after the cooker came. There are fewer diseases like diarrhea and the environment has improved. … I think burning the rubbish will bring good health to this community,” said Patricia Ndunge, as she fried onions on the cooker.

And it looks like the community cooker has a future: Kenya’s largest supermarket, Nakumatt, has pledged to pay for 20 more slum cookers.