- kewal sethi
China - looking into future
China - looking into future
a fantastic proposal based on an interview with deng yingtao, an economist who also studied hydrology and other subjects. he talks about a new developmental model. (based on the book 'a new development model and china's future' – deng yingtao; routledge 2014)
at the beginning of 1980s, chinese communist party set certain targets – removing poverty before the end of the century and make it fully modernized before 2050. at that time the consumption of energy was 0.6 ton coal equivalent per capita per year whereas it was 11 ton for usa and six in france, japan and germany. so how to ensure progress. china is an importer of oil, depending more on it than usa. only 25 % will be met from domestic resources by 2030. and oil producing countries are mostly part of pax americana.
what you need is out of box thinking. see a beautiful experiment. dealing with pigs manure is a big problem. to clean the stys, use plenty of water. channel the run-off water to water hyacinths. it will break down 80 % of the organic waste. then use azolla water fern (originally from germany). it will break down 80 % of the remaining waste. you get virtually clean water. it can be recycled. water hyacinth can be used to feed the pigs. azolla also produces feedstock. it is a sustainable agricultural cycle.
another scheme is biogas/green house - 4 in 1 technology. in the cold climate of north china, pig stys would be inside the greenhouse providing enough bio gas to light the houses and for cooking, bio mass can be used to produce horticultural crops.
but the big idea. china's water resources are mostly in south west. tibetan plateau and other mountain ranges prevent water from flowing north. china has plenty of water resources but 90 % of it goes waste. nothing flows to the dry north west. only yellow river flows north, others flow east or south. 90 % of population lives in the eastern part while most of mineral and water resources are in the west. with five or six developed countries dominating oil resources, china has to look towards other sources of energy.
the solution is to carry the water to arid north west but that means crossing mountains, lifting water over them. hydrological power is not the solution because as much will be spent in lifting as produced. yingtao says, "one day i saw something which made me jump with joy. i quickly gathered all the information i could, read up on it to confirm what it was. this new technology transformed the way i was thinking about this water transfer project … we could use wind power to raise water"
vertical-axis wind turbines offer 360 degree generation i.e. they can use wind from any direction which increases their efficiency five times. because stresses are different, the mechanical demand on system is not the same at all. older technology costs 10000 rmb per kilowatt. thermal power station usually cost 4500 – 5000 rmb. with vertical axis turbines the cost is halved, roughly equal to thermal power generation. by designing a pump which works with vertical axis turbine, the price can be further halved. further it need not be connected to national grid which will further reduce the cost. there is lot of wind on the hengduan mountains. on one square kilometer of land, you can put five 2500 kw vertical axis turbines. wind turbines can work for 4000 hours continuously. this chinese technique is unique in the world. normal turbines can produce only a few dozen kw.
wind power is known as garbage power because there is so much variability. loads can go from 20 % to 250 percent. no transmission network can cope with it – they need constant loads. but if you are raising water, there is no problem. you do not have to link it to national grid. when the wind is slow, one pump starts. when it goes up, more pumps start. there are no transmission losses. virtually 100 % of electricity produced is used. once water is raised over the watershed, it will flow normally. if the terrain is good, you can even get hydroelectricity from it. you can build reservoir at suitable places.
you can use kites and balloons with turbines tied to them. at height of several kilometers, the wind never stops. its velocity is much more and it is constant. there will be grids but if you can resolve the issue of synchronizing variable supply and variable demand, energy intensive industries like aluminum smelting are feasible.
tunnels construction technology is developing. japan has machines which can bore tunnels with 16-17 meters diameter. chinese machinery has 13 meters diameter capacity. the water can flow through tunnels, can be lifted over saddles where necessary. where geology makes it difficult to make tunnels, the place can be avoided. we don't have to follow a flat line. we can make bridges where necessary. bridge construction technology has also improved. mega dams are not necessary, we can have series of small dams. big ones where geology allows it, smaller ones elsewhere.
this combination of wind power and hydrology is the key stone. with that everything falls into place.