Green roofs are nice statements but it's my understanding that you will be doing the world a bigger favor by putting solar cells on your roof, or some form of passive solar lighting system. Maybe a partial green roof if you have more roof area or the house is shaded too much for PV.

Why would you think that? A green roof isn't made with nasty chemicals. Helps lower heating and cooling costs and is just plain cool. So are solar cells. Have there been studies on what saves more energy?

In the comments of this post, many people concluded that it was possible to combine solar panels and a green roof without much trouble. In fact, since the green roof lowers the operating temperature of the solar cells, their efficiency (and durability?) can be increased.

"Have there been studies on what saves more energy?"

Maybe you should do the research and get back to us.

'generating power from natural forces is inexpensive because a much smaller energy system is needed. The design of the home is the key'
I completely agree. When you design a home to be as efficient as possible and to take advantage of what nature has to give at that location, such as wind, sun, hydro, geothermal, landscaping, whatever, you can end up with a house that requires very little or no extra energy to keep warm and cool. And integrated house design should include analyses of electrical and water consumption patterns from the beginning rather than as an add on. By learning how the inhabitants of the house will 'live' in the house, the architect can determine how to incorporate design features and energy and water saving appliances that both facilitate the inhabitants' lifestyle and comfort and reduce energy, electricity and water to a minimum. In doing so, renewable energy systems - PV, solar thermal, wind, etc. - can be relatively small and therefore relatively cheap. It is important to have good 'green' technologies, but without good 'green' design you may end up trying to cool a sauna with a soccer field of PV panels or heat a freezer with a local forest.

'The Greeks considered anyone who didn't use passive solar to heat a home to be a barbarian!' I liked this statement from one of the links. I had to mention it as I think it relavent. I think an appropriate add-on to this statement would be the term oil-addicted in front of barbarian.

The problem with designing to a families lifestyle is that houses change hands and then the whole balance is out of whack. Also it isn't cheap to design or be green. That needs to change before it becomes a standard and not fringe.

'The problem with designing to a families lifestyle is that houses change hands and then the whole balance is out of whack.'

This is partially true; if a house is designed to meet a certain families lifestyle, a new and radically different family in the house may end up not using the house as was designed. However, if you don't design a house around a family's lifestyle, then not only will the second family be using the house inefficiently, so will the first. Furthermore, I think there are many families who do remain in their homes throughout their lives and even more who do so over most of their lives. A final point would be that most homes today are already designed based around the lifestyle of the purchasing family; the problem is that this purchasing family does not ask the architect to consider integrated design features that help improve resorce use efficienies. Rather they ask the architect to design in a sauna (which a second family may not use at all) or to design in an extra large kitchen (which may be too large for the second family) and so on. Even if the architect doesn't design in efficiency based on lifestyle patterns, design will be greatly influenced by the purchasing families lifestyle patterns. Patterns which may be at odds with those of new future owners. So the architect might as well design for energy efficiency while he or she is at it.

'Also it isn't cheap to design or be green. That needs to change before it becomes a standard and not fringe.' I think your statement about design is true. I studied architecture a number of years in high school and university (before switching majors) and learned how focused on money many architects can be. Anything that requires greater effort on their part they will charge for dearly - I am speaking on a general level. I am sure there are architects that do not fit this bill. As for green technology and materials, I do not necessarily think they have to be significantly more expensive to use in a house with one big catch - the home has to be really well designed!