In 2006, ASHRAE published a GreenGuide (not free) that contains useful information for those working on green design projects. In this publication, ASHRAE provided several "GreenTips." These 39 tips have been extracted from the publication and are now available free to the public in a downloadable pdf. These GreenTips cover a wide range of topics from recommendations for certain design programs to different hybrid mechanical/passive systems, and water systems. Each tip includes a brief general explanation, some considerations or pros and cons, as well as a list of sources for further information on the topic. Click here look for the link in the last paragraph that will take you to the free pdf.