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Large scale hydropower will fail in Tibet due to freezing temperatures

Hydropower dams on the Tibetan plateau will be inefficient or inoperable due to freezing temperatures and exacerbate climate change, warns geologist Yang Yong

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The frozen Yarlung Tsangpo river just before it enters India - freezing temperatures pose a risk to hydropower infrastructure (Image by Yang Yong) 

Driving into Tibet is already an increasingly popular choice for tourists – the pristine scenery is some of the best anywhere in the world. But the views are now spoiled by dense networks of power lines and pylons. And as the power grid develops these eyesores will spread to every corner of the Qinghai-Tibet Plateau.  

On November 23 Tibet’s first large hydropower plant at Zangmu went into operation, sparking huge concern in the Indian media. The new plant marks the start of large-scale hydropower generation in Tibet.

The dam at Zangmu stands 116 metres high at 3,310 meters above sea level. It has a reservoir capacity of 86.6 million cubic metres of water and a generating capacity of 510 megawatts. The project itself will not have a large impact on the local ecology or hydrology, but a single dam is unlikely to be profitable – a cascade of dams will be needed, passing water downstream in coordination with each other. Such large scale development will inevitably threaten the rivers of Tibet and the entire Plateau. If this approach is not changed the rivers of the Qinghai-Tibet Plateau face disaster.

During the 13th Five-year plan large hydropower dams will be developed on the Jinsha (upper Yantgtze), Lancang (Mekong), Nu (Salween) and Yarlung Tsangpo, creating the highest density dam cluster in the world.

It is not known exactly how many hydroelectric plants Tibet already has, but there are less than 10 larger ones (50 megawatts or more) and over a hundred smaller ones. These are often inefficient and short-lived. Most of the hydroelectric plants I have studied at an altitude of 3,500 metres or more in Sichuan, Qinghai and Tibet suffer from ice blockages during the five months or so of freezing temperatures every year, meaning little or no electricity is generated. The cold weather also damages equipment and greatly increases maintenance costs.



Tibet is not suited to large-scale hydropower development for two reasons. First, the Qinghai-Tibet Plateau is the source of Asia’s major rivers, and these are mostly fed by glacier meltwater, rather than precipitation. This means flows are highly seasonal and changeable and so power supply is unstable and the frozen winters and iced-up rivers can damage generating equipment.

Second, due to the quality of land in Tibet’s river valleys and the geological conditions, creating reservoirs to regulate water flow is problematic. This reduces the ability of dams to regulate power generation and respond to higher demand. These two factors make development of hydropower in Tibet more technically and economically challenging.

Power networks will ruin scenery

The Qinghai-Tibet Plateau is the roof of the world, a highland of global significance for its river sources and ecosystems. It should be developed for its environment, rather than for its hydropower, and the region itself does not need large amounts of power. Wind and solar power and other complementary sources of electricity should be used to supply the region’s own needs, but exporting electricity will not be worthwhile and the power grid required would cause huge damage to the area’s natural beauty.

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Tibet is a world-class tourist destination for both international and domestic tourists, who are attracted by its natural scenery and ancient culture. Already some popular routes and sights are marred by power lines, making them less valuable for tourism.

Tibet has a range of different environments, and power supply plans can be designed accordingly. For example the south-west of Tibet has a network of rivers and so small-scale domestic hydropower generation can be used. In other areas there are good prospects for wind and solar power, and a smart power grid for the plateau should be investigated. But hydropower should not be relied upon to supply Tibet with power, much less for exports. The costs and dangers are too great.

Large-scale hydropower may worsen climate changes

The Qinghai-Tibet Plateau is one of the world’s most geologically active regions. The earth’s crust here is still rising, causing frequent earthquakes and powerful fractures. The geology of the rivers is complex, the climate variable, the flora and fauna diverse and the ecology vulnerable.

The most obvious sign of climate change is the melting or even disappearance of glaciers – something that is happening now on the plateau. For over three decades I have been made multiple visits to the plateau every year, especially the Sanjiangyuan region, where the Yangtze, Yellow and Mekong rivers rise.

In October this year I found that surface temperatures at the huge glacier sources on the south-west slope of Geladan and Purog Kangri in the heart of northern Tibet were 30 degrees Celsius, with ground temperatures around 40-46 degrees Celsius. The sustained heat was leaving the glaciers scarred with gullies carved by meltwater runoff, some cut right down to the rock below the glacier, with the sounds of rocks colliding in the water echoing around.

The effects of climate change on hydropower development are unknown. Large hydroelectric plants may also exacerbate climate change – most will be built in arid valleys and so the resulting reservoirs will cause local climate change, increasing the overall complexity of the problem.

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匿名 | Anonymous

地震灾害与中国西部大型水利工程

我通过电子邮件认识了杨勇,当时他已经在西藏雅鲁​​藏布江上游完成了一个关于河流起源和生态的调查。我建了一个关于中国西部河流起源的网站(www.shangri-la-river-expeditions.com),杨勇希望我把他远征的经历写进去。2006年,我儿子特拉维斯在通天河(主要流经青海地区)漂流时遇到了杨勇。2009年,特拉维斯邀请我和杨勇一同在金沙江(长江中段)漂流,当时汶川地震刚刚过去一年,八万多人在那场地震中失去了生命。杨勇认为地震与大坝导致紫坪铺水库(位于四川省都江堰市)的水位变化有关。随后,杨勇通过特拉维斯请我撰写关于地震灾害与中国西部大型水利工程的报告(http://probeinternational.org/library/wp-content/uploads/2012/08/JohnJacksonreport-July24.pdf),但该报告却没有得到政府的重视。杨勇是少数反对在中国西部兴建大坝的人,希望政府能够正视他的忠告。

彼得·温

Earthquake hazards and large dams in western China

I first encountered Yang Yong by email after he had completed a first descent and ecological reconnaissance of the upper Yarlong Tsangpo in Tibet (headwaters of the Bramaputra). I had started a website about first descents of rivers in western China (www.shangri-la-river-expeditions.com) and he wanted me to add his expedition to my site. In 2006, my son Travis met him while rafting the Tongtian He (headwaters of the Yangtze in Qinghai, north of Tibet). Travis invited both us to raft the Jinsha Jiang (middle reach of the Yangtze) in 2009, a year after the Wenchan earthquake disaster which killed 80,000 people northwest of Chengdu. Yang Yong was convinced this quake was caused by dam operations affecting water levels of the Zinpingpu Reservoir on the Min River near Wenchuan. Later, through Travis, he asked me to write a report on earthquake hazards and large dams in western China (http://probeinternational.org/library/wp-content/uploads/2012/08/JohnJacksonreport-July24.pdf), which was largely ignored by the Chinese government. Yang Yong is one of the few highly respected anti-dam voices in western China. Hopefully someday the government will heed his warnings. Peter Winn

Default avatar
匿名 | Anonymous

奇怪的文章---杨勇是谁?

这篇文章很奇怪,因为事实证据很混乱。

文章中说“河流补给主要是冰川融水,降水补给能力弱,水文季节性差异大,不稳定”。世界上许多地方源源不断的流水都是来自缓慢而平稳的积雪冰川融水,这就是为什么欧洲国家很担心阿尔卑斯山的积雪减少---他们可能不得不修建大坝来应对积雪的减少。为什么西藏就不能这样做呢?

文章中还提到“多级开发,上下调剂补偿,是需要的。如此大规模的系统开发又必然危及西藏乃至青藏高原上的江河”。这也没有道理。多级水坝将调节河流流量,进而减小对水存量的需求和对大坝的影响。这并不会影响整个高原。

以上疑问归结为一个问题---杨勇是谁?除了希望保持青藏高原纯净的自然环境,他讨论电网建设这些事情的合理性又在哪里?

A strange article - who is yang yong?

This is a strange article because the facts seem rather confused.

It says that rivers "are mostly fed by glacier meltwater, rather than precipitation. This means flows are highly seasonal and changeable". Many parts of the world depend on the slow and steady melting of snowpack and glaciers for a steady flow; that is why European countries are worried about a reduction of snow in the Alps - they may have to build dams to replace the snow storage that could be lost. Why is Tibet different?

It also says that "a cascade of dams will be needed, passing water downstream in coordination with each other. Such large scale development will inevitably threaten the rivers of Tibet and the entire Plateau". That also does not make sense. A cascade will regulate the flow of one river, reducing the need for storage and thus the impact of the dams. It will not affect the entire plateau.

This is why I ask - who is Yang Yong and what is her/his qualification to talk about these matters, apart from wishing to preserve the pristine environment?