And not only is it technically impossible

Recently,there have been some imaginative attempts to make polycrystalline and ribbon silicon which are lower in cost than high-quality single crystals;
近日,出现了一些有想象力的尝试制造比单晶体更便宜的多晶体和缎状硅;
but to date the efficiencies of these apparently lower-cost materials have been unacceptably small.
但是就目前看来,这些看起来便宜的材料的效用要比预计的小.
Although many scientists were aware of the very low cost of amorphous solar cells,they felt that they could never be manufactured with the efficiencies necessary to contribute significantly to the demand for electric power.
尽管许多科学家在意那些便宜的无规则的太阳能细胞（估计是一种可以将太阳能转化为电能的东西：译者注）,但是它们觉得这些细胞永远不可能被制造的足够有效,达到能满足电力需要的必要要求.
译者：意思就是,这个amorphous solar cells虽然是个好东西 ,但是制造出来了也没有,因为发的电太少 ,不能满足需要

最近，有在费用低于优质单晶是的一些有想象力的尝试使多晶和丝带硅; 但是迄今 这些明显更加便宜的材料efficiencies是不能接受地小的。
Although许多科学家知道无定形的太阳能电池的非常低成本，他们认为他们不可能制造与必要的效率极大造成对电power.?的需求...