Electricity is a secondary energy source
電是二級能源
Electricity is the flow of electrical power or charge. Electricity is both a basic part of nature and one of the most widely used forms of energy.
電是指電能的傳遞或電荷的流動。電既是自然界的基本構(gòu)成要素之一，也是人類普遍使用/應用最廣泛的能源形式之一。
Electricity is actually a secondary energy source, also referred to as an energy carrier. That means that customers get electricity from the conversion of other sources of energy, such as coal, natural gas, nuclear, solar, or wind energy. These sources of energy are called primary energy sources. The energy sources used to make electricity can be renewable or nonrenewable, but electricity itself is not renewable or nonrenewable.
電實際上是一種二級能源，也被稱作能源載體。也就是說，人類通過其他形式的能源轉(zhuǎn)換獲得電，例如：煤、天然氣、核能、太陽能、風能。這些能源叫作一級能源，有些是可再生能源，有些是不可再生能源。但是電本身 沒有可再生或不可再生之分。
Electricity use has dramatically changed daily life電的使用極大地改變了日常生活
Before electricity became available more than 100 years ago, houses were lit with candles and kerosene lamps, food was cooled in iceboxes, and rooms were warmed by wood-burning or coal-burning stoves.
100多年前電能尚未開發(fā)/尚未為人所用，人們用蠟燭或煤油燈照明，用放滿 冰塊的箱子冷卻/冷藏食物，靠柴爐或煤爐來取暖。
Scientists and inventors have worked to decipher the principles of electricity since the 1600s. Some notable accomplishments were made by Benjamin Franklin, Thomas Edison, and Nikola Tesla. Benjamin Franklin demonstrated that lightning is electricity. Thomas Edison invented the first long-lasting incandescent light bulb.
17世紀以來，科學家和發(fā)明家們致力于破解電的原理。本杰明?富蘭克林， 托馬斯?愛迪生，尼古拉?特斯拉取得的成就最為矚目。本杰明?富蘭克林證明 了閃電的本質(zhì)即是電。托馬斯?愛迪生發(fā)明了第一個持久耐用/能持久照明的白熾 燈泡。
Prior to 1879, direct current (DC) electricity had been used in arc lights for outdoor lighting. In the late 1800s, Nikola Tesla pioneered the generation, transmission, and use of alternating current (AC) electricity, which reduced the cost of transmitting electricity over long distances. Tesla’s inventions used electricity to bring indoor lighting to homes and used electricity to power industrial machines.
1879年之前，使用直流電的弧光燈被用作室外照明。19世紀末，尼古拉?特斯拉開創(chuàng)了交流電的發(fā)電、輸電和使用，降低了遠距離輸電的成本。尼古拉?特斯拉的發(fā)明使電用于室內(nèi)照明，也使電驅(qū)動工業(yè)機器。
Despite its great importance in daily life, few people probably stop to think what life would be like without electricity. Like air and water, people tend to take electricity for granted. But people use electricity to do many jobs every day-from lighting, heating, and cooling homes to powering televisions and computers.
盡管電對于我們的日常生活意義重大，但是幾乎沒人會停下來思考如果沒有電我們的生活會變成什么樣子。人們往往把電看作是理所當然，就像空氣和水一 樣。但是，人們每天用電來做很多事情，家庭照明、取暖、制冷/降溫，還有電視、電腦的供電。
