Population growth, resource depletion, unstable ecosystems, and economic strains are some of the interlinked and uncertain hazards that deteriorate the life experiences of people. Conservation of resources and greater reliance on renewable energy systems sized to the home and perhaps even constructed by the homeowner can provide part of the solution. This book, written by engineers but accessible to anyone with a good calculator, shows how to design and manage technologies that are small-scale, decentralized, conservative, and environmentally gentle.