Wednesday, January 30, 2013

LED Billboards More Likely To Cause Highway Crashes

The advance in LED technology and price drop have made big LED billboards more and more common to be installed along roadside for advertisement purpose. New Swedish study, Effects of electronic billboards on driver distraction, proves that big electronic billboards indeed would distract drivers and increase road accidents.

The study found that there was a link between electronic advertising billboards along major roads and car crashes. The Swedish Transport Administration recently approved the installation of 12 electronic billboards for a trial period along a three-lane motorway with heavy traffic running through central Stockholm, Sweden, to evaluate the effect of electronic billboards on visual behavior and on driving performance.

In the study, a total of 41 drivers were recruited to drive an instrumented vehicle passing four of the electronic billboards during day and night. A driver was considered visually distracted when looking at a billboard continuously for more than two seconds, or if the driver looked away from the road for a high percentage of time. Dependent variables were eye-tracking measures and driving performance measures.

Data showed that drivers had a significantly longer dwell time, a greater number of fixations and longer maximum fixation duration when driving past an electronic billboard compared to other signs on the same road stretches. No differences were found for the factors of day and night, and no effect was found for the driving behavior data.
Electronic billboards have an effect on gaze behavior by attracting more and longer glances than regular traffic signs. Yet, more studies are necessary to prove whether electronic billboards attract too much attention and constitute a traffic safety hazard.
 

Sunday, January 27, 2013

Thin-Film Solar Cells Efficiency Catching Up Silicon

Solar panel manufacturers are racing to improve the cell's efficiency. The advantages of better efficiency mean smaller footprint, lower balance-of-system cost and cheaper installation cost. Thin-film solar cells have several advantages over conventional silicon cells. They can be deposited onto a substrate, are flexible and less sensitive to shadowing and high-temperature.

The latest breakthroughs in thin-film cell efficiency are:

(1) CdTe (cadmium telluride): 18.3%  by GE. It is a full percentage higher than the 17.3% achieved by First Solar last year.

(2) CIGS (copper-indium-gallium-diselenide): 20.4% by Swiss Federal Laboratories for Materials Science and Technology (Empa) on a flexible polymer substrate foils. Empa breaks it own record made about 2 years ago of 18.7%.

(3) CIS (copper-indium-selenium): 19.7% by Solar Frontier, beating a decade-long mark of 18.6%.

(4) Organic tandem cell: 12% by Heliatek.

It's important to remember, though, that these technologies first have to become manufacturable at cost and scale, and perform in the field at least on par with what's already out there. Translating these champion cell numbers to module performance, silicon cells typically lose about 10% of their efficiency; for thin-film it's more like 20%.

Thursday, January 24, 2013

Fight Tsunami Using Artificail Coral-Reefs

 
Kogami is an NGO that was established seven years ago in order to reduce loss of life from earthquakes and tsunamis. The group believes in using natural solutions to flight disasters. One of the projects is using artificial coral reefs to break up wave energy of tsunami before it reaches the shore.

Kogami built a prototype scheme in Sumatran city of Padang, a place under heavy threat from tsunamis. It uses the technology of cathode accretion, a chemical process putting a small electricity in the water to draw calcium carbonate, the same substance forming coral reefs, suspended in the seawater and deposits onto an iron-based skeleton. The calcium slowly accumulates, forming an artificial reef and wave barrier.

With this technology, Kogami wished to construct a new and robust warm water artificial coral reefs to enhance the local economy and reduce the power of waves approaching the coast.
In addition to reefs, it could also be used to build structures that would serve as community hubs and also work as tsunami protection. When disaster strikes, the local community would go to the structures for refuge. Because the buildings are literally grown from the ocean environment, the hope is that they would be more resistant to the damage caused by a tsunami.

The project is still very much in the conceptual phase, but in area where tsunamis are a constant threat, new design paradigms that are resilient to the damage of a giant wave are going to be necessary.

Tuesday, January 22, 2013

Is A BPA-Free Bottle Really Safe?

Nowadays, when I shop for milk and water bottles for my daughters I tried to find those which labelled "BPA-Free" in the hope that they would be safer for them. Are these bottles really better than the old "BPA-contained" bottles?

BPA, acronym of Bisphenol-A, an estrogen-mimicking compound found in plastic, store receipts, soup cans, water bottles, and other products, is potentially toxic. In the past few years, more and more companies are removing BPA from their products. Before the removal of BPA companies have to find an alternative compound to replace it and it is called BPS (Bisphenol-S), which only with a word different. Even with the so-called safe alternative to BPA, BPS disrupts estrogen hormones in disturbingly similar ways to BPA. The safe alternative isn’t so safe after all.

In a paper recently published in Environmental Health Perspectives, researchers from the University of Texas examined the effect of BPS in rats, where they found that BPS can mimic the body’s estrogen hormones, just like BPA.

Now, how safe is BPS? BPS is basically the same molecular structure as BPA. The only difference is that one of the linking element in the middle of the molecule is a sulfur. According to Cheryl Watson, co-author of the paper and a professor of biochemistry and molecular biology at the University of Texas Medical Branch, molecules with the same shape, you would suspect them to act on the same receptors. And yet, companies started using BPS as a BPA replacement without knowing whether it was harmful.

Part of the reason that BPS was used as an alternative is that it doesn’t leak out of plastic as much as BPA. But Watson said, "The problem is that hormones and things that mimic hormones are so potent that if you have just tiny amounts of them they still cause these responses."

It’s hard to say exactly how BPS affects human health; it’s new enough that extensive studies haven’t been done. BPS is suspected to impact human health just like BPA, which has been linked to diabetes, asthma, issues with neuro-development, obesity, and more.

The question now is that should we pay more to buy those BPA-free products? I am also not sure!

Thursday, January 17, 2013

The Top 10 Smartest Asia/Pacific Cities

How do we define the phrase of "smart cities"? Boyd Cohen, a urban and climate strategist, has created a Smart Cities Wheel which look at 6 different components of the cities to determine their smartness. The components are,
(1) Smart economy
(2) Smart environment
(3) Smart government
(4) Smart living
(5) Smart mobility
(6) Smart people



Using data from several sources, including Mercer Quality of Living report, the Siemens Green City Index, Rutgers, etc, Cohen comes up with the top 10 Asia/Pacific smart city rankings.
  1. Hong Kong
  2. Singapore
  3. Seoul
  4. Tokyo
  5. Auckland
  6. Sydney
  7. Kuala Lumpur
  8. Taipei
  9. Shanghai
  10. Osaka
Hong Kong topped the list for its multiple government-funded universities, high rate of transit rides per capita, overall ICT use, and Octopus - a smart card system that residents can use to pay for schools, parking, transit, and more. Singapore came in second for a number of smart and green features, including a clean and efficient public transportation system and extensive use of rainwater capture.

Wednesday, January 16, 2013

NASA Satellite's Images of Recent China Air Pollution

China has started the new year with off-the-charts levels of air pollution. NASA's Earth Observatory satellite Terra shows the choking layer of haze in Beijing.

Below image taken on 3 January of Beijing and surrounding areas, before the attack of the haze, shows a clear sky with sign of winter snowfall on the ground.


Looking at the image taken on January 14 below, China was covered by a layer of haze. During taken of this image, the sensors at U.S. Embassy in Beijing recorded a PM2.5 measurement of 291, which was 11.6 times higher than the World Health Organization PM2.5 safety limit of 25.


PM2.5 is a tiny particle in the air with size less than 2.5 micrometers. It can easily penetrate deep into the our lung. The airway's ability to block this fine particle is relatively weak and so bacteria and viruses carried by it can directly enter the airway and infect our body. Hospitals in China have reportedly admitted 20% to 30% more patients then usual with respiratory issues that were likely caused by breathing heavily polluted air.

Picture taken on Jan. 12, 2013 shows sunlight being reflected in a window of a building in Beijing.

Air pollution is a major problem in China due to the country's rapid pace of industrialization, reliance on coal power, explosive growth in car ownership and disregard for environmental laws. It typically gets worse in the winter because of weather conditions and an increase in coal burning for heating needs. The government has said that it would place regulations on auto emissions in Beijing areas to ease the hazy conditions.

Monday, January 14, 2013

Off-Grid Solar Power Plan For Myanmar Rural Electrification

SPCG Public Company Limited, a Thai main board stock exchange (SET) listed solar plant developer, intends to build off-grid solar plants to supply electricity to Myanmar's rural populations. Each plant would have a capacity of less than 2 MW and cost 7-14 million baht (~ US$233,000 - US$467,000).

Myanmar is falling short of electricity supply demand. Only 2,500 MW is available for the 55-million population. According to the Asian Development Bank, of the 40 million people living in rural areas, only 16% has access to grid power. The majority of the rural population depends on diesel generators.

Myanmar lacks small solar plants to serve rural communities. Investors from large economies such as China, India and Japan are keen to develop big projects. SPCG saw an opportunity to develop small plants to provide power in the short term. It expects to develop a mixture of renewable energy projects, such as solar plants with mini-hydropower plants, to take advantage of Myanmar's vast water resources. Wind power is also a possibility.

SPCG has eyed two potential locations, with the first project likely to be in Mandalay or Yangon. The company has secured prospective partners in Myanmar already, with a plan to set up a joint-venture company in the second half of this year. Construction will start in 2014.

Sunday, January 13, 2013

The World Greenest Office

Bullitt Center, a new office building of Bullitt Foundation, in Seattle will be the greenest, most energy-efficient commercial office building in the world. It combined a lot of different existing technologies and methods to create a structure that’s a showpiece for green design--and a model for others to follow.

According to Bullitt Foundation, the goal of building the center is to change the way buildings are designed, built and operated to improve long-term environmental performance and promote broader implementation of energy efficiency, renewable energy and other green building technologies in the Northwest of U.S.

The center will be a self-sustainable building using solar PV system for 100% of the energy consumption, all water will be provided by harvested rainwater, natural lighting, indoor composting toilets, a system of geothermal wells for heating, and a wood-framed structure. All these made the center the greenest and most efficient office building in the world.

Bullitt Center is the first conventional office building in the U.S. to get all of its water from rain. The rainwater collected will be stored in a 56,000 gallons cistern located in the basement. Tenants are expected to use about 500 gallons of water per day, so the cistern should be able to keep the building hydrated during a 100-day drought.

The composting toilets come with air compressors, a soap solution, and water. Once a toilet has been used, the waste will be moved down into one of its 10 composters located in the basement. The waste decomposes with help from wood shavings and water.

It is expected that tenants will begin moving into the Bullitt Center this month.

Saturday, January 12, 2013

Record Cell Efficiency Of CIGS Solar Thin-Film Material

Japanese solar panel manufacturer Solar Frontier has achieved a new thin-film solar cell efficiency record of 19.7%. The material used was not the conventional silicon based, rather it was a novel material called Copper-Indium-Gallium-Selenide (CIGS). This efficiency improvement was done through collaboration with Japan’s New Energy and Industrial Technology Development Organization. The new record broke a previous record of 18.6%, which stood for 10 years. Efficiency improvements help reducing the footprint of solar panels, which has practical, convenience and cost benefits, such as a reduction of installation cost.

CIGS can be deposited onto a substrate, rather than sawed from a solid material like silicon wafer cells are. However, this has been a challenge. Notably, CIGS solar panels can be flexible which open up to a variety of useful applications. CIGS is also less sensitive to shadowing and high-temperature. This makes it a better solar material in the countries, like Malaysia, which has a high chance of cloudy and rainy days.

Thursday, January 10, 2013

LED Efficiency Improved By 55% Thanks To Firefly

All LED materials suffer an internal reflection problem. Much of the light generated is reflected back into the material itself and is lost as heat. Light travel slower inside the LED than in the air. When it come to the LED/air interface it will encounter an internal reflection. This is like having a semi-transparent mirror at the interface that permits some light to escape and some reflect back into the material. The result is lower light output and heat removal problem.

Researchers at the University of Namur, Belgium, has drawn inspiration from firefly to solve the internal reflection problem. They make a LED overlayer pattern that mimicked the unique surface geometry of firefly's cuticles. They deposited a layer of light-sensitive material on top of the LED and then exposed sections with laser to create triangular factory-roof profile. The researchers adjusted the dimensions of the protrusions to a height and width of 5 micrometers to maximize the light extraction. This has improved the LED light output by 55%.


The researchers think that the technology should be able to be commercialized within the next couple of years. This new research was recently published in the Optical Society’s (OSA) open-access journal Optics Express.

Wednesday, January 9, 2013

Using Soda Can & Drill To Make Cotton Candy

How do you make cotton candy at home? Below shows you an easy DIY method.

Materials
  • Soda can
  • Threaded rod (Length : height of the can + 4~5 inch)
  • Nuts and Washers
Tools
  • Portable stove
  • Safety pin
  • Power drill
Construction
1. Use the safety pin to make tiny holes on the lower half of the can.


2. Make 1 hole on the top and 1 hole on the bottom of the can for the shaft (threaded rod).
3. Tie nuts and washers to secure the threaded rod on the top and bottom of the can.

 
4. Attach the top end of threaded rod to the power drill.

Making the cotton candy
1. Add sugar into the can.
2. Melt sugar in the can over low flame.
3. When sugar is melted, turn off the heat and spin the drill.


Visit http://publiclaboratory.org/notes/kosamari/11-14-2012/diy-cotton-candy-maker-0 for more info.

Tuesday, January 8, 2013

Australia's Solar Electricity Has Dropped Below Grid Parity

On 30th November 2012, I talked about German grid-connected solar PV installed cost has dropped to RM6.40 per watt, which was half of Malaysia installed cost. Now, another country also reported that its solar electricity generation cost is half the cost of grid power. 

The average installed cost of rooftop PV for Australia households has dropped to US$2.19 per watt (~ RM6.70 per watt). As most Australians who own a roof can currently borrow money at around 7% or less, this means the cost of electricity from rooftop solar for typical Australian is now about 12 cents (about 37 Malaysian cents) a kilowatt-hour, which is less than half the average cost of grid electricity in Australia.

Of course, thanks to Renewable Energy Certificates, Australian households don’t pay the full cost of their solar systems. Most installation will save about 68 cents a watt. Without this subsidy, the installed cost would be US$2.87 per watt. This makes the full production cost of solar electricity about 15 cents (45 Malaysian cents) per kilowatt-hour, which is still close to half what Australians pay for grid electricity.

In Malaysia, we are still looking at more than 70 Malaysian cents per kilowatt-hour for solar electricity. Hopefully, we the launch of solar FiT scheme, Malaysia solar installed cost could quickly reduce to the level of Germany and Australia. By then, the nation could rely less on fossil fuels by switching to solar energy.

For more info please visit: http://cleantechnica.com/2013/01/07/solar-electricity-now-under-half-the-cost-of-grid-power-for-australian-households/

Thursday, January 3, 2013

Hazardous Wastes Found In Our Daily Life

Lots of the products we use every day are potentially hazardous substances. You can find them in your kitchen, bathroom, office, garden, etc. Because of their chemical nature they can poison, corrode, explode or burst into flame when handled improperly. When discarded, they become hazardous wastes.

Motor oil, paints, pesticides, antifreeze, wood preservatives, batteries, CFL and fluorescent light tubes, and many household cleaners contain solvents, petroleum products, heavy metals or other toxic chemicals. When throw in the trash or poured down the drain, the hazardous chemicals contained can injure people, contaminate drinking water sources or pollute the soil.

For Example:

Each 4-feet fluorescent light tube (light tube we use in our home, office, parking lot, etc) contains about 10 mg of mercury. According to the USA Environmental Protection Agency, the allowable mercury level in drinking water is less than 2 micro-gram per liter. So, each fluorescent tube is capable of contaminating 5,000 liters of water.

Tips:

DO NOT dispose of hazardous waste in the trash, down the drain, onto the ground or on the street. All of these methods may result in health and/or environmental problems.

DO NOT store corrosives, flammables and poisons together. Separate these containers.

DO NOT repackage chemical products in containers that are normally used for products or soft drinks. Children have died from drinking chemicals stored in soft drink bottles.