The author is a correspondent with the Tibet branch of Xinhua News Agency.
NINETY kilometres northwest of Lhasa, the capital of the Tibet Autonomous Region, there is a basin set amidst snow-clad mountains. The streams, lakes and even the ground are constantly shrouded in steam, despite the surrounding cold.
This steam used to hiss into the air, wasted, until the Yangbajain geothermal experimental power station, the biggest in China, was built in 1977.
The Yangbajain station has a total installed capacity of 7,000 kw and is one of the key power suppliers to Lhasa. Lhasa residents use electricity for light, cooking, and boiling water for purification. In the past the city relied on hydroelectric power stations, which cannot supply electricity in winter, when the rivers freeze over.
The local people's government plans to install five more thermoelectric generators, with a capacity of 3,000 kw each, by 1990.
The geothermal resources now being exploited are generally about 200 metres deep. Chinese and French geologists estimate that there is a 500 steam reservoir five or six kilometres deep and a 1,000C magma field 14 to 35 kilometres down.
China is co-operating with the United Nations Development Programme and with Italy to further explore the geothermal resources around the station.
Chinese geologists believe that there is a big geothermal belt in the southern Tibet Plateau. The 2,000-kilometre-long belt extends from the Ali area in western Tibet through Kashmir, Afghanistan, Iran and Turkey, and finally joins the Mediterranean geothermal belt. To the east, it extends to China's Yunnan Province, Burma and Indonesia, finally joining the Pacific geothermal belt. The belt is quite wide, running from the northern slope of the Himalayas in the south to the Gangdise Mountains in the north, and north of the Nyainqentanglha Mountains.
This geothermal belt along Tibet's border is estimated to have an average heat flowing volume of 680,000 kilocalories per second. The heat vented each year is equivalent to that generated by burning 3 million tons of standard coal. It is clear that Tibet has great energy potentials, although it has little oil, coal or natural gas.
Chinese geologists also believe that the geothermal belt in Tibet is the most diverse in China. More than 600 geothermal fields and spots have been found in the region, including hot springs, salty hot springs, hot ponds, hot marshes, hot fields and a warm lake.
In Nyamring County in southwestern Tibet lies China's biggest geyser. When it erupts, a 20metre-high, 2-metre-wide pillar of boiling water is topped by a 50metre pillar of steam. Hot water falls down with a long rumble of thunder which can be heard a dozen kilometres away. The eruption always lasts three or four hours.
The largest of the three geysers in central Tibet's Namling County is on a precipice by a river. Like a pump. the geyser spurts hot water 10 metres away. The steam makes a beautiful rainbow under the sunlight.
East of the Yangbajain geothermal field there is a warm lake, 16 metres at its deepest point. This 7,000-square-metre lake is the biggest and deepest warm lake in China. In bright sunny days, the steam cloud coming off the surface of the lake reaches up 100 metres.
The temperature of the lake water is the same, about 45℃,whether in the bottom or on the surface, by the shore or in the centre. The same is true for the hot springs.
The hot springs and warm lake were considered spiritual places by the Tibetans in the past. They were forbidden areas until about 20 years ago, when they were put to work to serve the people.
To make full use of the geothermal energy, a 1,500-squaremetre greenhouse was built near the Yangbajain geothermal power station. About 22,000 to 25,000 kilogrammes of vegetables are grown there annually. It is going to be expanded into one of the key vegetable suppliers for Lhasa, according to a decision of the regional people's government. It will cover 50,000 square metres and produce 75,000 kilogrammes of vegetables a year.
Several sheepskin tanneries and chicken farms are to be built near the power station, to use the wasted hot water.
Some bathhouses have been built in spring areas to treat patients. The spring water is also used to treat the disease of pasture animals.
The first natural spring swimming pool was built in Xaitongmoin County in southern Tibet, which is about 4,000 metres above sea level.
In Cona County, north of the Himalayas, all the families have dug ditches to divert the spring water to their bathrooms. In the winter they also divert the water to pits under their wooden floors, to warm their houses. The county is 4,600 metres above sea level and the temperature in the evening is always below 0C, but all their rooms are kept warm at about 18C.
In each room there is a hole on the floor and every member can fetch hot water by just taking off the lid.
Another geothermal power station with an installed capacity of 3,000 kw is going to be built in the Ali area. Before long the electricity will be used to power Shiquanhe township, the capital of the area.
The geothermal resources are being used in other provinces and cities. Each year China saves about 3 million tons of coal by using geothermal energy in farm production.
(This article appears on page 28, No. 35, 1984)