Read the following passage and mark the letter A, B, C, or D to indicate the correct answer to each of the questions
Renewable energy technology has developed drastically in recent years, with improved efficiency and lower cost. But one major issue is that they don‟t provide a perpetual supply of energy. Wind and solar farms only produce energy when the wind is blowing or the sun is shining - but we need electricity all the time. A possible way around this would be to generate solar energy in space.
There are many advantages. A space-based solar power station could orbit to face the Sun 24 hours a day. The Earth‟s atmosphere also absorbs and reflects some of the Sun‟s light, so solar cells above the atmosphere will receive more sunlight and produce more energy. But one of the key challenges to overcome is how to assemble, launch and deploy such large structures. Using lightweight materials will also be critical, as the biggest expense will be the cost of launching the station into space on a rocket.
Many possible solutions have been proposed, including the development of a swarm of thousands of smaller satellites that will come together and configure to form a single, large solar generator. Meanwhile, researchers at the California Institute of Technology have outlined designs for a modular power station, consisting of thousands of ultralight solar cell tiles that only weigh as much as a playing card. At the University of Liverpool, researchers are exploring new manufacturing techniques for 3D-printing ultralight solar cells on to solar sails, which are foldable, lightweight and highly reflective sheets capable of harnessing the effect of the Sun‟s radiation pressure push a spacecraft forward without fuel.
There is still a lot of work to be done in this field, but the aim is that solar power stations in space will become a reality in the coming decades. Researchers in China have designed a system called Omega, which they aim to put into operation by 2050. To produce that much power with solar panels on Earth, you would need more than six million of them. Smaller solar power satellites could be operational even sooner.
For a long time, the concept of giant solar power stations floating in space, was mainly an inspiration for fiction writers. A century later, however, scientists are making huge strides in turning the concept into reality. Our hope is that they could one day be a vital tool in our fight against climate change.
(Adapted from bbc.com)
