Building a Solar-Heated Pit Greenhouse Author:Greg Stone Introduction: — If you've always wanted a greenhouse, but you're scared off by the high cost of energy, take a close look at the solar pit. It's a greenhouse that combines the energy-conserving features of the traditional pit greenhouse with some newer techniques and materials used in modern, heated greenhouses. The result is a simple, inexpensiv... more »e structure that blends in with almost any environment and requires little or no heat from any source except the sun.« less