news20100809gdn1

[News] from [guardian.co.uk]

[guardian.co.uk > Environment > Solar power]

Be wary of 'solar for free' offers, householders told
With companies offering to fit homes with solar panels for free, experts say you can save more by paying for them yourself

Adam Vaughan
guardian.co.uk, Monday 9 August 2010 14.43 BST
Article history

{Homeowners would be better off paying for their own solar panels, say experts. Photograph: Dan Chung}

Householders tempted by a rash of new "solar for free" offers could double their financial savings by paying for the panels themselves, experts have warned.

The advice comes as installations of solar photovoltaic panels have exploded in the UK, with the number installed in four months in 2010 more than doubling on the whole of 2009 since a government financial incentive was launched in April.

Spurred by the new feed-in tariff scheme that pays small scale generators of green electricity, a glut of companies are offering to fit thousands of homes with solar panels for free. Under the "rent your roof" model, the companies earn the tariff worth approximately £835 a year and the homeowner benefits from an annual saving of around £110 off their electricity bill. Homesun, ISIS Solar and A Shade Greener are three of the firms planning to do a deal with more than 120,000 homeowners by 2015, with Homesun promising to fit 2,000 homes in the next 12 months.

But homeowners would almost certainly be better off paying for the solar panels themselves, even taking into account interest on a loan for the upfront cost of around £10,000 for a typical home. "Looking at the figures, it [paying for panels yourself] looks like a better deal on paper," Liz Laine, energy expert at Consumer Focus, told the Guardian. She added that consumers should go into such deals "with their eyes open". Simon Osborn, policy advisor at Which?, said: "If you have the means to pay for solar panels yourself, then you may well be better off arranging to have them installed yourself." Consumer Focus has also published a checklist of 24 questions people should ask before signing up, including who has liability if something goes wrong with the panels.

Under the "free solar" model, a homeowner would save in the region of £2,750 on energy bills over 25 years, the length of the tariff offer. By paying for their own panels with a loan at 7.7% interest repaid over 10 years and earning income from the feed-in tariff, they could save around £6,506 over the same period.

But the rise of such business models is exactly what the tariff was designed to do, say government and solar industry figures – drive innovation and solar take-up. Since the tariff started on 1 April, 12.12 megawatt peak (MWp) of solar panels have been installed at 4,822 homes, up from 3.8MWp in 2007, 4.42 MWp in 2008 and 5 MWp in 2009. Solar panel makers are responding to the demand, with Sharp announcing it will double annual production at its UK plant to 500 MW in December. The Wrexham plant, which currently employs 750 people, has seen the UK's share of its output rise from 1% to 10%.

"A large number of companies are setting up to do PV [solar photovoltaic panels]," said Ray Noble, solar specialist at the Renewable Energy Association (REA). "Things are moving from a cottage industry to building scale industry, and creating a high number of jobs too."

One UK solar energy company, SolarCentury, has seen its direct employees and network of installers rise from 200 staff in January to 350 now and predicts it will employ more than 500 by 2011.

The tariffs for solar and other renewable "microgeneration" are a key part of the UK's plan to cut carbon emissions and hit an EU target of generating a fifth of energy from renewable sources by 2020. The government forecasts installations driven by the tariff will account for 1.6% of the UK's electricity consumption in 10 years' time.

However, the bill for the government and the taxpayer is unlimited. The government predicts the cost will be around £8 on every energy bill by 2020, though there is no cap and the scheme could potentially be a victim of its own success. Spain last week announced it was slashing its feed-in tariffs for solar PV panels by up to 45%, which some experts believe was a result of the tariff being set too high initially.

The rate of the UK tariff, currently set at 43.1p per KWh for solar PV on existing properties, is fixed until 31 March 2012, when it will be reviewed before decreasing each year. There is disagreement between industry figures over whether the current solar gold rush could force an earlier review. "I think the rate of uptake will be so fast the government will have to do an emergency review (of the rates) or possibly suspend them," Alistair Roberts, project manager at energy co-op Renew, recently told the ENDS Report. "I don't think there's a risk of an emergency review in the next two years, as government needs as much help as possible to hit carbon targets," said Noble at the REA.

Solar is currently the most expensive form of renewable electricity per unit of energy produced, though some in the UK solar industry believe rising energy prices and falling production costs will help it match fossil fuel prices by 2013.

news20100809gdn2

[News] from [guardian.co.uk]

[guardian.co.uk > Environment > Wave, tidal and hydropower]

Hydroelectric dams pose threat to tribal peoples, report warns
Dams in Brazil, Ethiopia and Malaysia will force people off land and destroy hunting grounds, says Survival International

John Vidal, environment editor
The Guardian, Monday 9 August 2010
Article history

{Construction begins on the Gibe III hydroelectric dam in southern Ethiopia. Photograph: Xan Rice for the Guardian}

Giant hydroelectric dams being built or planned in remote areas of Brazil, Ethiopia, Malaysia, Peru and Guyana will devastate tribal communities by forcing people off their land or destroying hunting and fishing grounds, according to a report by Survival International today.

The first global assessment of the impact of the dams on tribes suggests more than 300,000 indigenous people could be pushed towards economic ruin and, in the case of some isolated Brazilian groups, to extinction.

The dams are intended to provide much-needed,low-carbon electricity for burgeoning cities, but the report says tribal people living in their vicinity will gain little or nothing. Most of the power generated will be taken by large industries, it concludes.

At least 200,000 people from eight tribes are threatened and a further 200,000 people will be adversely affected by the Gibe III dam on the Omo river in Ethiopia. Ten thousand people in Sarawak, Malaysia, have been displaced by the Bakun dam,which is expected to open next year, and a series of Latin American dams could force many thousands of people off their land.

The authors say enthusiasm for large dams is resurfacing, driven by a powerful international lobby presenting them as a significant solution to climate change. Lyndsay Duffield, said: "The lessons learned [about the human impact of large dams]last century are being ignored, and tribal peoples worldwide are again being sidelined, their rights violated and their lands destroyed."

The report says the World Bank is one of the biggest funders of destructive dams, despite worldwide criticism in the 1990s for supporting such projects. Its portfolio now stands at $11bn, with funding up more than 50% on 1997.

The UN now subsidises dam building via the clean development mechanism (CDM), which allows rich countries to offset their greenhouse gas emissions by investing in clean energy in poor countries. The watchdog group CDM Watch says more than a third of all CDM-registered projects in 2008 were for hydropower, making them the most common type of project vying for carbon credits.

Concern is growing over the role of China, now the world's largest builder and funder of big dams. The Three Gorges Corporation, firm behind the controversial Three Gorges dam, which has displaced more than a million people from around the Yangtze river in the last 20 years, has been contracted to build a dam on the land of the Penan tribe in Sarawak. China's biggest state bank, the Industrial and Commercial Bank of China, may fund Gibe III in Ethiopia, to be Africa's tallest. The Chinese government has financed the majority of dams built in China, which account for about half the global total of large dams.

The report says tribes have borne the brunt of the development over the last 30 years. In India, at least 40% of people displaced by dams and other developmentprojects are tribal, though they make up just 8% of the country's population. Almost all of the large dams built or proposed in the Philippines have been on the land of the country's indigenous people.

The report accuses banks and dam builders of consistently underestimating the number of tribal people affected. "There is an endemic tendency within the dam industry to significantly underestimate the number of people to be affected by their projects," it says.

"The World Bank's review of big dam projects over 10 years found that the number of people actually evicted was nearly 50% higher than the planning estimates."

Survival International called for all hydroelectric dams on tribal peoples' land to be halted unless the tribes have given full consent. "In the case of isolated or uncontacted tribes, where consultation is not possible, there should be no development of hydroelectric dams on their territories," it said.

Danger dams

Ethiopia The Gibe III dam on the Omo river in Ethiopia threatens about 200,000 people from eight tribes in the Lower Omo valley. The dam will disrupt the annual flood the tribes rely on, destroying their livelihoods and leaving them vulnerable to famine. On the other side of the border in Kenya, 300,000 people who live on the banks of Lake Turkana will also be affected.

Brazil A series of dams is planned for the river Madeira. The Jirau and Santo Antonio dams will affect many tribes, including uncontacted groups known to live a few miles from one site. The Belo Monte mega-dam on the Xingu river would be the third largest in the world, and would devastate a huge area. Kayapó Indians and other tribes of the area have been protesting against the dam since it was proposed in the 1980s.

Malaysia The Bakun dam in Sarawak, due to be completed this year, has displaced 10,000 tribal people, including many semi-nomadic Penan tribespeople. The relocated Penan now cannot hunt, and struggle to support themselves on tiny plots of land. Sarawak plans 12 more hydroelectric dams, which will force thousands more people to move.

Peru Six dams have been proposed which would flood land along the river Ene, home of the Asháninka, the largest indigenous group in Peru.

Guyana More large dams are planned for the north of Brazil and southern Guyana, including the controversial Upper Mazaruni dam which was stopped after protests but is likely to be revived.

news20100809bbc

[Sci/Environment News] from [BBC NEWS]

[bbc.co.uk > News > Science & Environment]

Rice yields falling under global warming
Global warming is cutting rice yields in many parts of Asia, according to research, with more declines to come

By Richard Black
Environment correspondent, BBC News
9 August 2010 Last updated at 21:37 GMT

{Dark clouds hang over future farming under climate change, the study suggests}

Yields have fallen by 10-20% over the last 25 years in some locations.

The group of mainly US-based scientists studied records from 227 farms in six important rice-producing countries such as Thailand, Vietnam, India and China.

This is the latest in a line of studies to suggest that climate change will make it harder to feed the world's growing population by cutting yields.

{“We haven't seen a scenario where daytime temperatures cross over a threshold where they'd stop benefiting yields and start reducing them”
Jarrod Welch
UCSD}

In 2004, other researchers found that rice yields in the Philippines were dropping by 10% for every 1C increase in night-time temperature.

That finding, like others, came from experiments on a research station.

The latest data, by contrast, comes from working, fully-irrigated farms that grow "green revolution" crops, and span the rice-growing lands of Asia from the Indian state of Tamil Nadu to the outskirts of Shanghai.

Describing the findings, which are published in Proceedings of the National Academy of Sciences (PNAS), lead researcher Jarrod Welch said:

"We found that as the daily minimum temperature increases, or as nights get hotter, rice yields drop."

The mechanism involved is not clear but may involve rice plants having to respire more during warm nights, so expending more energy, without being able to photosynthesise.

By contrast, higher temperatures during the day were related to higher yields; but the effect was less than the yield-reducing impact of warmer nights.

However, if temperatures continue to rise as computer models of climate project, Mr Welch says hotter days will eventually begin to bring yields down.

{Warmer climates will bring changes to rainfall, potentially causing drought}

"We see a benefit of [higher] daytime temperatures principally because we haven't seen a scenario where daytime temperatures cross over a threshold where they'd stop benefiting yields and start reducing them," he told BBC News.

"There have been some recent studies on US crops, in particular corn, that showed the drop-off after that threshold is substantial," said the University of California at San Diego researcher.

The 2007 assessment of climate impacts from the Intergovernmental Panel on Climate Change (IPCC) concluded that although a modest temperature rise could increase crop yields in some regions, for "temperature increases more than 3C, average impacts are stressful to all crops assessed and to all regions".

A study published at the begining of last year concluded that half of the world's population could face a climate-induced food crisis by 2100, with the most extreme summers of the last century becoming routine towards the end of this century.


bbc.co.uk > News > Science & Environment]

Hidden graves found using chemical 'sniffer' technology
A "sniffer tube" could replace dogs in the arsenal of tools to locate hidden graves, say researchers.

9 August 2010 Last updated at 18:16 GMT

{Pinpointing a suspected gravesite is no easy task}

A new technique uses a long tube to quickly sample the air above suspected gravesites.

The specially coated tube can spot tiny amounts of a chemical linked to the breakdown of animal remains, up to months after the remains are buried.

The research is published in Forensic Science International and highlighted in New Scientist magazine.

The task is to outperform the premier detector of hidden explosives, drugs, or humans alive or dead: the sniffer dog. But as much as dogs can be trained, it remains unclear what exactly they perceive.

"We're not really sure what the dogs are sniffing or what they're focusing on," said Tom Bruno of the National Institute of Standards and Technology (Nist) in the US.

"And dogs can be difficult to control, and uncertain," he told BBC News. "Recently we've come to think dogs aren't sniffing an explosive, but cyclohexanone, a chemical used to re-crystallise the explosive.

"What if the bomb makers switch to using another chemical instead?"

In order to win out over the dog's abilities in finding hidden graves, Dr Bruno and his colleague Tara Lovestead adapted their "headspace analysis" technique, originally developed to detect explosives and more recently adapted to sniff out food spoilage.

Shedding light

At the heart of the approach is the use of a long tube lined with two materials: alumina, a porous but tough material that soaks up molecules from the air, and ninhydrin, a molecule that binds both to alumina and to the clues indicating a hidden grave.

“If you suspect there's something buried under a concrete slab, it's probably the best way”
Tom Bruno
Nist}

Almost all animal tissue is made up of proteins, which after death break down into constituent parts, some of which end up free in the air. In mammals, the structure of many of these decomposition products - with evocative names such as cadaverine - is known.

When these products encounter ninhydrin, a particular bond is formed - a bond that absorbs light of a particular colour.

At one end of the tube is a source of ultraviolet light and at the other a detector. The more decomposition products that settle in the tube, the more light gets absorbed along the way; the light level is then an indirect measure of the presence of decomposing flesh.

To set up their "gravesites" to be tested, the researchers placed rat cadavers on top of or buried underneath soil in a number of compartments. Other compartments were left with soil only.

Their detection technique accurately spotted the presence of the cadavers, at times ranging up to 20 weeks after burial - the decomposition process eventually exhaust the supply of proteins.

Dr Bruno says that the team will carry on applying the technique to a range of "sniffing" problems, and that they are already in discussions to commercialise the idea.

It may be some time before the technique can routinely outperform a dog's nose, but may become indispensable for cases in which a grave may be hidden beneath more than just soil.

"In large areas, it would be a supplement to other methods or dogs," Dr Bruno said.

"But in small areas, or if you suspect there's something buried under a concrete slab, it's probably the best way."