Alternate heating systems
There are alternatives to forced-air heating systems, particularly in mild climates such as California. Consider a grid-tied photovoltaic approach, which not only solves problems of storage (when compared with a complete solar space heating system) or go with a high-efficiency, split-system heat pump designed for residential use. Berkeley-based Sun Light & Power provide energy-efficient design and building solutions. More at [Dwell](http://www.dwell.com/green/].