Tanah Jakarta Berpotensi Ambles Jika Terjadi Gempa 5 Mw

[Republika, 15 Juni 2007]

Jakarta-RoL -- Tanah Jakarta cukup berpotensi untuk ambles, longsor, dan kehilangan daya dukung terhadap fondasi bangunan dan infrastruktur di atasnya jika terjadi gempa dengan skala di atas 5 Mw dan dengan kecepatan gempa permukaan di atas 0,1 gal (80 cm per detik kuadrat).

"Jakarta merupakan kota yang dibangun di pesisir, khususnya area di utara Jakarta. Jadi sebagian tanahnya dari jenis pasir, bukan jenis lempung," kata pakar geoteknologi LIPI, Adrin Tohari di Jakarta, Jumat (15/6).

Tanah jenis ini jika ditambah syarat lain yakni bersifat lepas (tidak padat) dan jenuh air, lanjut dia, maka cukup berpotensi terkena likuifaksi atau suatu fenomena hilangnya kekuatan lapisan tanah akibat beban getaran gempa.

Pada peristiwa ini lapisan tanah pasir berubah menjadi cairan sehingga tidak mampu menopang beban bangunan di atasnya dan mengakibatkan antara lain, hilangnya daya dukung atau kegagalan pondasi jembatan, mengakibatkan ground settlement yang dapat menimbulkan penurunan pada bangunan dan ground oscillation yang dapat menimbulkan kerusakan pada jalan.

Likuifaksi juga menyebabkan flow failure atau longsoran lereng tanah yang menimbulkan kerusakan besar pada jalan yang berada di atas tebing, menyebabkan lateral spread atau perpindahan menyamping pada permukaan datar dan menimbulkan kerusakan pada bangunan dan jalan.

Likuifaksi juga membuat lapisan pasir menyembur (sand boiling) dan menyumbat sumur. Ia memberi contoh ketika terjadi gempa Yogyakarta, sumur-sumur menyemburkan pasir dan tersumbat sehingga warga Yogyakarta yang rumah-rumahnya hancur karena gempa makin menderita dengan kekurangan sumber air bersih.

Selain itu likuifaksi juga bisa menyebabkan bouyant rise of buried structures yang menimbulkan ledakan pada pipa gas atau tanki bahan kimia terpendam di dalam tanah.

Namun demikian studi tentang struktur tanah di Jakarta sangat minim, belum ada pemetaan area mana saja di Jakarta yang mengandung lapisan pasir lepas dan jenuh air yang berbahaya jika didirikan bangunan di atasnya.

"Kesulitan kami melakukan studi struktur tanah di Jakarta karena Jakarta sudah terlanjur padat dengan aspal, beton dan bangunan, padahal studi geologi perlu menggali dan membor lokasi-lokasi yang ingin diketahui," katanya.

Sumber gempa bagi Jakarta, ujarnya, bisa berasal dari subduksi di sepanjang barat Sumatera hingga selatan Jawa, sesar di Jawa Barat dan gempa Krakatau yang memiliki rentang umur ledakan sekitar 200 tahun.Ditanya soal kerawanan reklamasi pantai di utara Jakarta, menurut dia, bisa saja dibuat menjadi tidak rawan likuifaksi asal lapisan tanah di bawahnya dipadatkan. antara

Pelletti II wood pellet heating with "mole"

Particularly suitable for the modernisation of old buildings and rooms with low ceilings

Karlsbad, 14.03.2007 - More and more builders and renovators are turning to future-proof wood pellet heating systems, and for good reasons. For one, heating with small wood pellets from natural wood shavings makes heating independent of fluctuations in fossil fuel prices and, secondly, only an extremely small amount of wood pellets need to be used thanks to innovations in combustion technology. Two handfuls of wood pellets are enough to bring ten litres of water to the boil, for instance, or for a four minute shower. Every seventh pellet boiler in Germany already bears the "Pelletti" name and comes from Paradigma Energie- und Umwelttechnik GmbH & Co. KG, according to a press release from the company. As a compact three-pass boiler with integrated regulator, the Pelletti offers almost the same comfort as modern gas and oil heating.

This innovative company from Karlsbad is now offering the "Pelletti II" complete package with all accessories and the Sonnen-Pellet Maulwurf retrieval system. Specifically, this "Made in Germany" combination package consists of the SystaComfort heating regulator, the Sonnen-Pellet Maulwurf retrieval system, a filling set, an impact protection mat, a suction and return-air pipe, a flow plate and mounting parts. The retrieval system is a special feature of the new complete package. It "digs" through the stored pellets like a mole and retrieves these as needed for the boiler. Paradigma have emphasised that this simple "visible" technology operates quietly and cleanly and with low energy usage. It allows for pellets to be extracted sparingly from the top so that there is no loss of quality.

Furthermore, this "mole" system can also accommodate approx. one third more filling volume in the same storage space and facilitates a high degree of spatial usage as there are none of the usual cavities in the storage area. Paradigma believes the Sonnen-Pellet Maulwurf retrieval system is particularly suitable for the modernisation of old buildings and rooms with low ceilings. A separate dry storage room or the PelletonMaulwurf fabric silo, which has been specifically designed for the new retrieval system, are suitable for storing the pellets. This dust-proof fabric silo with integrated Sonnen-Pellet Maulwurf retrieval system can be purchased in five different sizes. A closable access opening at the front of the silo ensures it is easy to maintain. Pelletti II with the Sonnen-Pellet Maulwurf retrieval system is available immediately from any of the more than 700 Paradigma specialist workshops nationwide.

Further information:
Paradigma Energie- und Umwelttechnik GmbH & Co.
KGEttlinger Str. 30
76307 Karlsbad
GermanyTel. 07202 / 922 - 0
Fax: 07202 / 922 - 100
http://www.paradigma.de/
info@paradigma.de

[diambil dari http://www.german-renewable-energy.com/Renewables/Navigation/Englisch/Service/aktuelles,did=196290.html ]

First biomethane plant with a feed into the natural gas network

Regensburg, May 15, 2007 - The Aufwind Schmack Group has opened a biomethane plant in Pliening, a trailblazer on the path to sustainable energy production. Biogas composed of biomethane is fed directly into the natural gas network of the Stadtwerke München (Munich's public utility company) here. Since December 2006, Bavaria's first and largest biomethane plant (in Pliening, east of Munich) has been producing biogas from raw materials. Biomethane is generated by using a pressure swing adsorption process. This is fed into the natural gas network of Stadtwerke München. This is a first-off, as Stadtwerke München is now the first energy supply company in Germany to have made its natural gas network available for transporting biomethane. The biomethane plant in Pliening is a project of RES Renewable Energy Systems GmbH from Munich and Aufwind Schmack GmbH Neue Energien. The plant is being financed and run with funding from the Aufwind Schmack Group, the Hessian State Bank and Lacuna AG. With E.ON Bayern AG, the project has a long-term bulk purchaser for the biomethane on its side.

Some 3.9 million standard cubic metres of biomethane and around 43 million kilowatt hours of energy will be produced annually for the natural gas network. Ferdinand Schmack, the CEO of Aufwind Schmack GmbH Neue Energien, which is responsible for planning and operating the plant, says that this corresponds to the annual natural gas use of approx. 1300 single family dwellings. He described the advantage of biomethane over biogas: "While biogas must be used locally to generate electricity, biomethane can be transported over the existing pipeline infrastructure and can be used like natural gas." Maschinenring Ebersberg e.V. is the local project partner and logistician for the biomass. Stadtwerke München is building on its commitment to renewable energy. One building block is the incorporation of biogas into its "natural gas fuel". Since April, 20 percent of this fuel has been made up of biogas at the energy supply company's petrol pumps in Von-Kahr-Straße 1 and Kreillerstraße 220. This should be possible for all natural gas pumps of the energy supply company in the coming year.

Further information:
Aufwind Schmack GmbH Neue EnergienSchwandorfer Straße 1293059 Regensburg

Phone:+49 (0)941 / 698730-17

Fax:+49 (0)941 / 698730-50

E-mail: mailto:gerald.marunde@aufwind.com

Internet: http://www.aufwind.com/

[diambil dari: http://www.german-renewable-energy.com/Renewables/Navigation/Englisch/Service/aktuelles,did=206804.html]

peta transjakarta

S. Pacific Unprepared for Tsunamis?

[Copied from Discovery Channel] Madeleine Coorey, AFP

April 3, 2007 — Australia's hasty reaction to the threat of a tsunami which hit the Solomon Islands contrasted sharply with a lack of equipment and expertise to warn South Pacific nations, experts said.

A massive undersea 8.0-magnitude earthquake spawned the deadly tsunami Monday that pounded the Solomon Islands and triggered emergency warnings around the Pacific of possible sea surges there.

Australian officials were aware almost immediately of the abnormally large quake and predicted from its size and location that there was a chance the country's east coast could be hit by a tsunami.

Beaches along Australia's east coast were quickly closed and ferries crossing Sydney Harbor stopped as officials anxiously awaited news.

But it took hours for any more information about a possible tidal wave to reach Australian cities because of a lack of equipment and expertise in the South Pacific, experts said.

"This was frightening in a sense that we were warned there could've been a tsunami, we were trying to work out the magnitude of it but we were shooting blind, and I don't believe this is good enough," said Peter Beattie, Premier of Queensland state.

The South Pacific needed more equipment, such as tide gauges and satellite-linked buoys, to measure ocean movement so that Australia and its neighbours could be better warned of tsunamis, expert Gary Gibson said.

"It was so frustrating for the first few hours not to have confirmation (of a tsunami)," said Gibson, chairman of the executive committee of the US-based International Seismological Center.

"The Pacific has the best tsunami warning system in the world. The South Pacific is not quite as well set up. You can be waiting a long time to get information."

Gibson said Australia's warning system had been upgraded following the devastating 2004 tsunami, caused by a massive undersea quake off the Indonesian island of Sumatra.
That tsunami killed 200,000 people around the Indian Ocean shoreline.

"It's a matter of priorities and the priority has been given to the northwest coast because of the possibility of big earthquakes from Indonesia," he said.

The Australian government has said it would review its system after the Solomons tsunami, although its early warning system was on track to be fully operational in 2009. By that time, officials should be able to make more accurate predictions of tsunamis.

Monday's information vacuum led to some overreaction in Australia, particularly in the northeastern city of Cairns, where hundreds of residents attempted to drive to higher ground, causing gridlock on low-lying roads.

That response, said Gibson, "was not based on reality."

Kevin McCue, director of the Australian Seismological Centre, said Australian officials should have used historical data to predict that any tsunami from the Solomons quake would not present a danger here.

"We should have known we weren't going to have a damaging tsunami," he told AFP. "I think it was just an overreaction to Sumatra."

He said Australia should help neighbours such as Papua New Guinea improve their warning systems by giving them equipment and personnel.

But he said no amount of money would help those most at risk escape a tsunami as there was only five minutes after a quake to seek higher ground.

"They don't have telephones, they don't have power. There's no way of alerting people on the ground in the most risky areas," he said.

David Walsh, of the Pacific Tsunami Warning Centre in Hawaii, said there was a large network of water gauges in the South Pacific which were used to determine the risk of tsunamis.

But he noted: "Many of the gauges are inoperable on any given day."

Palm Oil Failing as Biofuel

[Copied from Disovery Channel]
Arthur Max, Associated Press

April 2, 2007 — Only a few years ago, oil from palm trees was viewed as an ideal biofuel: a cheap, renewable alternative to petroleum that would fight global warming. Energy companies began converting generators and production soared.

Now, it's increasingly seen as an example of how well-meaning efforts to limit climate-changing carbon emissions may backfire.

Marcel Silvius, a climate expert at Wetlands International in the Netherlands, led a team that compared the benefits of palm oil to the ecological harm from destroying virgin Asian rain forests to develop lucrative new plantations.

His conclusion: "As a biofuel, it's a failure."

Scientists and policymakers from more than 100 countries are meeting in Brussels, Belgium, starting Monday to report on the impact of global warming, including storms, flooding and the extinction of plants and animals.

Then in May, the group intends to issue recommendations on how best to fight it, through new technologies and possible use of alternatives. The lessons of palm oil are sure to figure into their discussion.

Long a primary ingredient in food and cosmetics, palm oil derivatives caught on about five years ago as a source of renewable energy, spurred by subsidies in many European Union countries. Imports have risen 65 percent since 2002.

Palm oil is attractive because it is relatively abundant, cheap at about $550 per ton, and requires few or no modifications to existing power stations.

Unlike carbon-rich fossil fuels, palm oil is considered carbon-neutral, meaning the carbon emitted from burning it is the same as what is absorbed during growth.

But the result of intensified farming has been to unleash far more greenhouse gases than will be saved at power stations.

The report issued late last year by Wetlands International, Delft Hydraulics and the Alterra Research Center of Wageningen University in Holland studied the carbon released from peat swamps in Indonesia and Malaysia that had been drained and burned to plant palm oil trees. About 85 percent of the world's palm oil comes from the two countries, and about one-quarter of Indonesia's plantations are on drained peat bogs, the report said.

The four-year study found that 600 million tons of carbon dioxide seep into the air each year from the drained swamps. Another 1.4 billion tons go up in smoke from fires lit to clear rain forest for plantations — smoke that often shrouds Singapore and Malaysia in an impenetrable haze for weeks at a time.

Together, those 2 billion tons of CO2 account for 8 percent of the world's fossil fuel emissions, the report said.

Friends of the Earth, another environmental group, called the report "astonishing," and said it shows that harvesting palm oil for fuel is counterproductive. "It undermines the whole project," said a climate specialist for the group, Anne van Schaik.

The study was not independently verified by the U.N. Climate Change Secretariat in Bonn, Germany, or by the World Resources Institute in Washington, D.C., the two leading monitoring groups. But experts said the research appeared credible. It is due to be published for peer review later this year.

Deforestation is the No. 2 cause of greenhouse gas emissions after the burning of fossil fuels, said Jeffrey Dukes, a biologist at the University of Massachusetts who was not part of the research. He said clearing peat swamps for plantations is "a double whammy."

It not only releases carbon trapped over many millennia, but destroys the most efficient ecosystem on the planet for sucking carbon from the atmosphere, Dukes said.

Expanding production of palm oil is "a terrible decision. Whether or not it's consciously made, it's society going in reverse," he said.

Major power companies are divided on whether to continue or pursue palm oil generation.

Leon Flexman, of RWE npower, Britain's largest electricity supplier, said his company decided against palm oil after a year of study because it could not verify its supplies would be free of the taint of destroyed rain forest or peat bogs, he said.

The Dutch power company Essent announced in December it had stopped burning until it can trace and verify the sources.

Biox, a Dutch startup, said it plans careful scrutiny of palm oil sources but will proceed with construction of three 50 megawatt power stations that burn palm oil byproducts exclusively. That's enough electricity to light all the homes in Amsterdam.

"From the start, we knew we can't stay in business if we can't prove that production is sustainable," said Biox executive Arjen Brinkmann. "Until this report came out, peat lands was not an issue because we hadn't heard of it. Nobody had heard," he said, adding that it will now be a factor in the company's sustainability criteria.

So far, the reservations about palm oil do not seem to have affected the market. Production rose 6.6 percent last year and will increase another 5.5 percent this year to 37 million tons, according to Fortis Bank. Prices have risen 35 percent in the last year and are still rising, it said.

Kabar Maret

wah Progress besar buat JIWANDARU...

1. sukses perdana label JIWANDARU, semoga edisi berikutnya sama suksesnya
2. sukses kerja sama finansial dengan i-finance, semoga kerja samanya bisa ditingkatkan lagi
3. dah mulai bagi2 tugas yang spesifik

ayo, kembangkan ide, jiwa sehat badan juga harus sehat... pacu terus semangat dan kreatifitasmu...

and i get some quotes for jiwandaru's
challenge requires some adventurers [abie-jiwandaru]