In this part . . . Energy usage is becoming an increasingly important aspect of our personal lives. Energy costs are rising, a trend that will surely continue. Because of the political ramifications of obtaining the energy we need, we all can help mitigate the huge problems that our energy consump- tion creates. The easiest, and often the cheapest, way for each and every one of us to reduce energy consumption is by being more efficient with the energy that we use. In this part I explain general concepts about energy so that you can make the decisions that let you reach your own energy efficiency goals. I show you how to accurately assess and measure how you use energy in your home so that you can decide how to invest your own personal energy and time in making improvements. I also give you a simple way to analyze financial investments so that you can get the most bang for your hard earned bucks.