Arizona Republic: You know about the light bulbs, the twisty, energy-efficient kind that have become a symbol of the green movement. You can’t live in Arizona long before you hear about the benefits of shorter showers and desert landscaping. But changing a light bulb and soaping up faster are not separate acts. Energy and water are tightly connected, each requiring copious amounts of the other and each increasingly vulnerable to volatile supplies of the other. The connection is even more …