人们习惯性地低估了他们的能源消耗

　　【时事聚焦】 时下，低碳生活已经成为一种时尚，人们开始从生活的点点滴滴中来减少能源消耗，可实际上我们很多时候往往只关注于少量的能源消耗，如及时关灯，却忽视了我们的大型家用电器对能源的消耗，如加热器和干洗机等。具体请看以下《经济学家》周刊网站的一则相关报道：

　　People habitually underestimate their energy consumption

　　Environmental asceticism has created a vogue for upgrading light-bulbs and tweaking thermostats. But according to a new piece of research, many of these actions—however virtuous—arise from faulty perceptions of energy savings.

　　Shahzeen Attari of Columbia University and her colleagues used Craigslist, an online marketplace, to recruit 505 volunteers from across America. Each was asked to estimate the energy consumption of nine household devices (such as stereos and air conditioners) as well as the energy savings incurred by six green activities (like swapping incandescent bulbs for fluorescent ones). The researchers then compared the volunteers’ estimates with the actual energy requirements or savings in question.

　　Their results, published this week in the Proceedings of the National Academy of Sciences, suggest that although people do grasp basic energy trends, they are decidedly hazy on the details. On average, participants underestimated both energy use and energy savings by a factor of 2.8—mostly because they undervalued the requirements of large machines like heaters and clothes dryers. As a result, they failed to recognise the huge energy savings that can come from improving the efficiency of such appliances.

　　Miscalculations like these hinder conservation efforts. When asked to rank the single most effective way to save energy, participants typically endorsed activities with small savings, such as turning off lights, while ignoring what they could economise on larger devices. This suggests that people misallocate their efforts, fretting over an unattended lamp (at 100 watts) while neglecting the energy they could save by nudging their washer settings from “hot” to “warm” (4,000 watt-hours for each load of laundry).

　　A quirk of human psychology could help to explain these persistent underestimates. When calculating such things, people often adopt a familiar unit as a mental yardstick and then generate predictions based on that unit. As a side-effect, their estimates cluster too closely around the yardstick measure—a phenomenon called “anchoring”. In Dr Attari’s study, for example, the survey provided a reference measure by stating the amount of energy used by a standard light bulb. Participants may have responded by unconsciously anchoring their estimates to this value, compressing their predictions into the relatively low range of an incandescent bulb.