Passive Solar has been around for some time. In the 1970's many homes where designed with this feature. Where so many people wanted to "try" it for their new homes it was not as cost effective back then as it is today.
Passive Solar systems are unique and not dependent on electricity for a motive force. That is what makes them so economical. Applying some basic concepts of passive solar or radiant heat will show that it can be used in any climate.
Passive solar is implemented through design and using the natural properties of thermal energies. Basically passive solar relies on the concept of hot air rising and cooler air falling. Establish this in your home or water system and take advantage of passive solar energy.
For cooler climates there is the skepticism that this will not work because it is cold outside. On the contrary it is the sunlight that will be of a greater heat source due to the environment will not absorb as much sunlight. The only requirement here is providing a barrier between the environment and the heat transfer area of your device. While allowing sufficient radiant energy into your system.
