In 1983, when oil prices were still high in my area, I installed a ground-source heat pump in my brand-new, well-insulated, 1,60

admin2010-01-15  36

问题      In 1983, when oil prices were still high in my area, I installed a ground-source heat pump in my brand-new, well-insulated, 1,600-square-foot house. It cost several thousand dollars more than comparable systems that use oil, gas or wood, but I figured I’d recover my higher initial expense m a few years through lower energy bills.
     True, my heat pump runs on electricity -- an expensive commodity where I live. But most of its energy comes from the earth, a propylene-glycol solution circulates through 1,200 feet of two-inch-diameter plastic pipe buried three feet deep in a field next to my house. As it travels, the solution absorbs heat from the surrounding soil, even when soil temperature drops below freezing.
     My ground-source heat pump also offers important benefits that have nothing to do with economics.
   -- Minimal fire hazard -- no chimney, firebox, or heating elements -- only pumps, fans, and a compressor.
   -- Cleanliness -- no combustion products, thus no chance of my heating system polluting the indoor air, leaving scummy deposits on walls and furniture.
   -- Reliability -- solid-state electronic controls and sealed bearings almost eliminate breakdowns.
   -- No maintenance -- no wood to cut, ashes to haul, or chimney to clean.
   -- Convenience -- The system runs automatically, even switching from heating to air conditioning as needed. I can simply lock the door and go away for a day, week or month.
     Not only did I expect to start saving on energy costs immediately, but I also expected those savings to grow over the years as oil prices continued to soar. Since I was wrong about oil prices, the big dollar savings I’d hoped for haven’t materialized. Nevertheless, I am satisfied, all things considered.
One benefit the author mentions is that the system ______

选项 A、uses no electricity
B、has a fire-safety shutoff
C、docs not pollute the air in the house
D、requires less insulation in house walls

答案C

解析 本题询问该系统的优点。文中列举了五个优点,并有记号一一标出。与原文相比可 知,只有C项是属于优点之一的,原文为“Cleanliness—no combustion products, thus no chance of my heating system polluting the indoor air"。
转载请注明原文地址:https://kaotiyun.com/show/DXnK777K
0

最新回复(0)