http://suprastock.blogspot.com/2009/07/best-alternative-energ...
Echelon Corp. ( ELON ) is one company riding what's known as the green building wave. The company designs, builds and sells networks that connect machines and other electronic devices for the purpose of sensing, monitoring and controlling the world around us.
You see, before you can save energy, you've got to know where and when that energy is used (or wasted), and that means you need some very smart devices that can provide you with the data necessary to do so.
The future of greener buildings is in what's called energy consumption or "negawatt" management. The idea behind negawatt management is that a kilowatt saved is a kilowatt earned. The easiest, fastest, cheapest and, ultimately, cleanest form of energy is the one that never has to be produced in the first place. But before you can save a negawatt, you first have to identify it.