| 阅读理解。 |
| Solar electric systems pay off most quickly for consumers who use a lot of energy because extra charges are given for heavy use, but the solar system still makes sense for low-energy users such as myself. So much of Americans' carbon footprint results from buildings-about 43%, according to the U.S. Department of Energy. I'm in a household of 1.5 (mom and 7-year-old), and we use only about 4 kilowatt hours of electricity per day, something we've managed through behavioral changes, such as turning off the lights in rooms after we've exited, and through in-home efficiencies (效率), such as swapping out all my light bulbs for energy-saving ones and using power boards that can turn off DVD players, coffee makers and other electrical equipment. Using less electricity means I can get by with a smaller, less expensive solar system that not only covers my use but also produces a credit on my power bill. Going solar also meant my house was upgraded with a time-of-use meter. This type of meter allows me to receive credit for the electricity I produce during peak hours when electricity costs the most, but pay the least for the electricity during off-peak hours, when I recharge my cell phone and laptop and perform other tasks requiring power. The downsides are that I am tied in to the grid (电网) and still affected by power failure, and I now have solar panels (太阳能电池板) that need to be cleaned. It's a subject of debate, but REC Solar said dirty panels decrease energy production by 6% to 8%.Many panel producers recommend cleaning panels at least once during the summer. I wash mine whenever they look dirty or dotted with bird droppings, which is about every other week. I think $6,000 is a small price to pay, not only for panels that should produce my next 20 years of electricity, but also for the greenhouse gases I'm not creating. |
| 1.What is mainly talked about in this article? |
| A. The ways of cutting power bills. B. The tips on reducing electricity use. C. The benefits of using solar systems. D. The importance of protecting the environment. |
| 2.Why does the writer recharge her mobile phones during off-peak hours? |
| A. To save credit. B. To save time. C. To save energy. D. To save money. |
| 3.The underlined word "downside" in Paragraph 4 is close in meaning to ______. |
| A. discount B. disadvantage C. disapproval D. disagreement |
| 4.The author cleaned her power panels ______. |
| A. to make them work properly B. to protect the environment C. to make them look better D. to avoid power failure |