英语翻译Ian Edmonds,an environmental consultant with Solartran i

英语翻译
Ian Edmonds,an environmental consultant with Solartran in Brisbane,Australia,has designed a giant engine with a balloon as its "piston".A greenhouse traps solar energy,providing hot air to fill the balloon.As the balloon rises,it pulls a tether,which turns a generator on the ground.Once the balloon has reached 3 kilometres,air is released through its vent and it loses buoyancy.This means less energy is needed to pull the balloon back down again,resulting in a net power gain (Renewable Energy,DOI:10.1016/j.renene.2008.06.022)."It is like a huge two-stroke engine,with a capacity of 45 million litres,a stroke of 3 kilometres,and a frequency of one revolution per hour," says Edmonds.
For roughly the same cost as wind power,Edmonds has calculated that a large 44-metre-diameter recreational balloon could generate 50 kilowatts,enough to supply energy to about 10 homes.Doubling the diameter of the balloon would increase power production tenfold,substantially reducing costs,he says.
Using air heated by the sun to generate power has been attempted before:solar towers use the rising air to turn turbines.But a prototype solar tower in Manzanares in Spain proved too short even at 200 metres,limiting the amount of energy that could be captured from the rising air.Building towers of 500 metres or more has so far proved too expensive.
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澳洲布里斯班 Solartran 公司的环境顾问伊安 埃德蒙设计了一款巨大的引擎.用气球当它的活塞.
先在温室里收集太阳能,形成的热空气把气球灌满上升,到了设计高度,拉绳启动地面的发电机.
气球离地 3 公里时,活阀释放空气让气球开始回落.不不费吹灰之力就回收了气球,再重复上升的动作.（参看工业部再生能源期刊 Renewable Energy,DOI:10.1016/j.renene.2008.06.022).
"就像一个巨大的,4500万公升的二行程引擎,一个行程3公里,一个小时一往复." 埃德蒙说.
和风力发电成本相当,按照埃德蒙计算,44米直径的休闲气球可以供电50千瓦,足供10个家庭所需.如果用88米直径的大气球,可以产生10倍的电力,单位成本更低.
前人尝试过太阳晒热的空气发电:阳光塔群利用热空气推动涡轮机发电.西班牙曼扎那瑞的实验雏形证明了,即使塔高设计到了 200米,热空气产生的动力仍嫌不足.如果因此把太阳塔加高到 500米,完全不合成本效益了.