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April, 2012:

Establish low-emission zones in city

As David Akers-Jones points out, there are ways the government could facilitate the removal of dirty old buses from our roads (“Get rid of filthy buses with loans”, April 30).

The suggestion of bridging loans to allow the bus companies to retire these clunkers a few years early would be a simple, low-cost solution. But the often cited figure of buses accounting for up to 40 per cent of roadside pollution is slightly erroneous as they actually only account for 6 per cent of respirable suspended particulates across Hong Kong.

The higher figure was a Transport Department estimate of the possible contribution to roadside pollution in busy commuting corridors at peak times – essentially the worst-case scenario of the most number of buses on the road when the pavements are full of people going to work.

If the department actually wanted to reduce roadside pollution there is an even cheaper or near-zero cost solution to reduce the effect of dirty buses.

Simply make these busy commuter roads and congested tunnels low-emissions zones at peak times. Not only would this ensure bus firms use the latest Euro engine vehicles, where the most benefit can be derived, it would also stop old commercial diesel vehicles clogging up and polluting these roads during the rush hour.

Edward Rossiter, Tai Wai

People still misusing recycle bins

In the report, “Give us more bins to boost recycling” (May 2), you say that “once a recycling bin is contaminated with non-recyclable rubbish, it effectively becomes a conventional bin that will end up in a landfill site”.

But why does it become contaminated?

A few years ago, I had recycle bins installed in my village.

To this day, whenever I take my paper, plastic and metal out, the bins are either filled with ordinary rubbish or the wrong items are in the wrong bins.

On a recent trip, the paper bin was filled with styrofoam lunch boxes with half-eaten food spilling out. I can’t decide whether people are lazy, ignorant or just wilfully obtuse.

The bins are clearly labelled and colour coded; you’d think people would have figured out how they work by now.

Randall van der Woning, Tai Po

Napier welcomes Hong Kong’s green guru

Published on Monday 30 April 2012 12:00

HONG Kong’s secretary for the environment has heard from a Capital biofuel expert during an official visit to Scotland.

Edward Yau toured the Biofuel Research Centre at Edinburgh Napier University as part of a European green technology trip encompassing cities in Sweden, Denmark, Scotland and England. As part of the Scottish leg, Mr Yau also met with Minister for Environment and Climate Change, MSP Stewart Stevenson.

Napier has strong links with Hong Kong’s growing renewables sector, working with biofuel sector players including airline Cathay Pacific.

Mr Yau’s visit to the university follows a visit by the current chief executive of Hong Kong, Donald Tsang, in September 2011.

Professor Martin Tangney, director of the Biofuel Research Centre at Napier, said: “It was an honour to welcome Mr Yau and the Hong Kong delegation to the campus, and to be able to share some of the successes we’ve achieved.”

Biofuel Research Centre

The Biofuel Research Centre undertakes research into biofuel, product analysis and provides information on biofuel to academia, government and businesses. We look at ways in which biofuels including biobutanol can be used in everyday life, thus reducing environmental impacts of fossil fuels.

Our research involves the analysis of industrial biomass for conversion to biofuel, and research into new and sustainable sources.

We also work with businesses in Scotland to encourage the use of sustainable renewable energies as an alternative energy source. We can offer businessesfeasibility funding and provide a broad range of business support functions including a range of free workshops.

Watch our video on new super ‘whisky’ biofuel to power cars. Contact us to find out more

> B

Biobutanol – the superior biofuel

Butanol is a 4-carbon alcohol originally central to a number of industrial chemical processes. It is now recognised as an important transport fuel – with superior characteristics to ethanol.

Butanol is produced by solventogenic clostridia via the Acetone-Butanol-Ethanol fermentation. The history of the ABE fermentation stretches back to the early 1900s and it was once only second to ethanol as the largest industrial fermentation. Its demise was ultimately triggered by the availability of cheaper alternatives from the petrochemical industry. The search for a sustainable biofuel has now established biobutanol as a important transportation fuel.

Butanol as a transport biofuel

Unlike conventional biofuels, such as ethanol and biodiesel that are mainly derived from food-based feedstocks, biobutanol is an advanced biofuel that can be derived from non-food sources and used as a stand alone transportation fuel or blended with petrol or diesel. Its inherent chemical properties make it superior to ethanol for use in combustion engines:

  • With 4 carbons, butanol has more energy than ethanol – 25% more energy per unit volume.
  • Butanol has a lower vapour pressure and higher flashpoint than ethanol, making it easier to store and safer to handle.
  • Butanol is not hygroscopic while ethanol attracts water. Ethanol has to be blended with petrol shortly before use. Butanol can be blended at a refinery without requiring modifications in blending facilities, storage tanks or retail station pumps.
  • Butanol can run in unmodified engines at any blend with petrol. Ethanol can only be blended up to 85% and requires engine modification.
  • Unlike ethanol, butanol may also be blended with diesel and biodiesel.
  • Butanol is less corrosive than ethanol and can be transported using existing infrastructures

Air pollution exposure during pregnancy and reduced birth size: a prospective birth cohort study in Valencia, Spain

Findings from this mother and birth cohort study in Valencia, Spain, suggest that prenatal exposure to outdoor air pollution, measured as NO2, affects the anthropometric development of the fetus, reducing its length and head circumference and increasing the risk of having a small for gestational age (in weight) baby.

Background: Maternal exposure to air pollution has been related to fetal growth in a number of recent scientific
studies. The objective of this study was to assess the association between exposure to air pollution during
pregnancy and anthropometric measures at birth in a cohort in Valencia, Spain.
Methods: Seven hundred and eighty-five pregnant women and their singleton newborns participated in the study.
Exposure to ambient nitrogen dioxide (NO2) was estimated by means of land use regression. NO2 spatial
estimations were adjusted to correspond to relevant pregnancy periods (whole pregnancy and trimesters) for each
woman. Outcome variables were birth weight, length, and head circumference (HC), along with being small for
gestational age (SGA). The association between exposure to residential outdoor NO2 and outcomes was assessed
controlling for potential confounders and examining the shape of the relationship using generalized additive
models (GAM).
Results: For continuous anthropometric measures, GAM indicated a change in slope at NO2 concentrations of
around 40 μg/m3. NO2 exposure >40 μg/m3 during the first trimester was associated with a change in birth length
of -0.27 cm (95% CI: -0.51 to -0.03) and with a change in birth weight of -40.3 grams (-96.3 to 15.6); the same
exposure throughout the whole pregnancy was associated with a change in birth HC of -0.17 cm (-0.34 to -0.003).
The shape of the relation was seen to be roughly linear for the risk of being SGA. A 10 μg/m3 increase in NO2
during the second trimester was associated with being SGA-weight, odds ratio (OR): 1.37 (1.01-1.85). For SGAlength
the estimate for the same comparison was OR: 1.42 (0.89-2.25).
Conclusions: Prenatal exposure to traffic-related air pollution may reduce fetal growth. Findings from this study
provide further evidence of the need for developing strategies to reduce air pollution in order to prevent risks to
fetal health and development.

Download PDF : Air Pollution Exposure during Pregnancy & Reduced Birth Size

Public housing estates to get energy-efficient lights


The government is installing energy-efficient light fittings in public housing estates.

Work started this month and will continue until September 2015, when all the 142 estates’ public areas are expected to have the new lights.

The fittings would save 33.11 million kWh of energy and reduce emissions by 23,179 tonnes of carbon dioxide each year, said Ho Wing-ip, a chief manager in the Housing Department.

Ho said one million light fittings would be replaced. Each would lead to an annual saving of HK$47 in power charges.

“Replacing each light fitting is basically the same as planting one tall tree” in terms of reducing carbon dioxide, he said.

Each light costs HK$260 – HK$60 more than an old one – and has a life expectancy of 5-1/2 years.

The lights have electronic ballasts, which enhance their energy efficiency, Ho said, compared with the traditional electromagnetic ballasts.

“The only thing that needs to be changed after 5-1/2 years would be the electronic ballast inside. The rest of the light can be reused,” he said.

The ballasts cost HK$130 each – HK$100 more than electromagnetic ones.

Ho said the old light fittings would be dismantled and their parts would be recycled.

Public housing estates with older light fittings were slated to have their lights replaced first, he said.

The first stage involves 50 estates and will cost HK$260 million. Work is already being done at Oi Man Estate. Lok Fu, Tai Wo Hau, Kwai Shing West and Kwai Shing East estates are among those scheduled next.

LED light fittings were another energy-efficient option, but they cost more, Ho said. An LED light costs about HK$800 to HK$1,000 and is very sensitive to heat.

“LED lights would burn out or grow dim after being exposed to the sun’s heat for too long. This is also why we chose not to use them.”

Follow fine example set by Shenzhen

Clear the Air says: the actual way forward is to use hybrid electric buses as used in London. These have the power to climb hills and use a small Euro V engine to charge the batteries as the bus runs as well as

charging whenever the brakes are applied.

SCMP – Follow fine example set by Shenzhen 30 April 2012

Hong Kong should take full advantage of the scheme in Shenzhen, where more than 50 per cent of the city’s combustion-engine buses are to be replaced with electric or hybrid ones by 2015.

One way in which the Hong Kong government can ensure that air pollution levels go down is by reducing pollutants emitted by cars or public transport operators.

The administration could follow the example set by Shenzhen and massively cut emissions of carbon dioxide.

At least with electric buses we would have zero emissions of PM2.5 [health-threatening fine suspended particulates].

Air pollution has adversely affected the quality of life of citizens and the economy.

It poses a grave threat to public health.

For all our sakes, it is time to take action and adopt a scheme similar to the one in Shenzhen.

Some people say that the cost of such a conversion of buses would be too high, but the change does not have to take place in one go; it can be part of a gradual process.

We can achieve this aim by approaching the problem with patience, ensuring that everyone can eventually breathe clean air and that Hong Kong is a pleasant place to live.

Kenneth Ho, Tseung Kwan O

Get rid of filthy buses with loans

SCMP – 30 April 2012

On Sunday, April 22, I felt lucky to be living on a high floor above the street-side pollution and in the sunshine.

On the radio, I heard more warning messages about high levels of pollution for this most liveable of cities. People of my age were advised to stay indoors.

I understand that the expense of equipping our bus companies with virtually non-polluting buses (say HK$3 million per vehicle) is not possible given the cap on their profits and the return to their shareholders.

Why, when we have the funds available, can we not lend the money to the companies to buy the buses and stop all this business of fiddling about with catalytic converters year after year?

Of course, it would not be possible to do this all at once but say a long-term loan for 300 buses a year would begin to make a difference. Also, it would send a cheer from the choking travellers and, incidentally, district council voters of Causeway Bay.

David Akers-Jones, Yau Ma Tei

Environment Bureau, ‘experts’ ignore alternatives to waste incinerator

SCMP – 28 April 2012

I found it interesting that Professor Poon Chi-sun, director of Polytechnic University’s research centre for environmental technology and management, has remarked of the waste incinerator issue that the current discussion by lawmakers “has become politicised” and is “not rational” (“Two ways to burn our trash, both with flaws”, April 22).

This follows legislators’ refusal to support the incinerator plan, and the Environment Bureau’s withdrawal of its funding request. Yet the issue has long been politicised and irrational.

In 2005, an incinerator was proposed as part of a comprehensive waste strategy introduced by the government. Though the strategy appeared rational, politics soon led to proposals being watered down or sidelined until incineration emerged as pivotal for the city’s waste management.

A proposed mega-incinerator was given the fancy-sounding title of “integrated waste management facility”, even though it was not integrated and would be little but a glorified bonfire. Incredibly, a site selection process led to the preferred location being an artificial island to be built beside Shek Kwu Chau, in a beautiful coastal location that’s a prime site for the globally endangered finless porpoise.

Various reasons were given, among the more ludicrous being that the incinerator island would boost local tourism. Yet the real reason for preferring Shek Kwu Chau was surely political: there’s no nearby major population centre with people who might protest.

A rational debate over the incinerator would surely involve the Environment Bureau and its consultant giving a balanced view of the pros and cons of the project.

Instead, information has been more akin to propaganda, with incineration touted as being near perfect – even though cases worldwide show there are abundant problems, including poisonous emissions and toxic ash – and alternatives derided or dismissed out of hand.

Plasma gasification is among these alternatives. It has been left to incinerator opponents to uncover information on this and other options.

Sadly, even waste “experts” receiving government funding have been far from immune from politicization, seeming too prone to support the incineration-focused policy under Chief Executive Donald Tsang Yam-kuen and too ready to downplay or provide disinformation about ways to treat trash without primitive bonfires.

Martin Williams, director, Hong Kong Outdoors

FEnvironmental Law Conference 2012: Enforcement and Awareness (27 April 2012) – Powerpoint handout

Download PDF : Legal & Policy Bases for Sustainable Development in Hong Kong

Download PDF : Environmental Law Conference 2012[v.5]

Understanding Air Pollutants and Air Quality Standards

Download PDF : appendix_f

Update of WHO air quality guidelines

Download PDF : E91399