Green Credential is a publisher for people interested in joining the new Green Economy.   We have experts in several fields:  green building, solar, and energy audits working with us to help students, professionals, and workers get up-to-date in America’s workforce …and get their Green Credential!

Green Credential produces helpful study guides, quizzes, and practice exams to direct you to maximize your time studying for the Green Collar industry.


Who’s behind Green Credential?  Greencredential.com is a website started by  Parker Williams.  To provide information about the NABCEP Entry Level Exam, the LEED exam, and green building and solar in general.

Parker Williams is a green design consultant and has his LEED AP BD+C and NABCEP entry level certifications and a professional degree in architecture from Ball State University. He has worked for internationally known green architects, obtained a Master of Architecture in sustainable design  degree from University of Texas at Austin’s School of Architecture, and currently lives in Indiana.  He has taken over 48 hours of Advanced PV Installation courses.

Best of luck to you all! Cheers!
Parker W.

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Help us out, we give 1% of ALL NET Profit from this website to SOLAR AID, a non-profit that seeks to spread photovoltaic technology to developing countries around the world. http://www.solar-aid.org


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Parker Williams, LEED AP BD + C



The infor­ma­tion con­tained on greencredential.com and any pub­li­ca­tions or other study mate­ri­als pub­lished by the author of greencredential.com is for infor­ma­tional pur­poses only, which is to be used as a study tool for the NABCEP  and BPI exam. Sum­maries, meth­ods of study, tips and tricks are only rec­om­men­da­tions from the author, and read­ing any infor­ma­tion on greencredential.com and any pub­li­ca­tions or other study mate­ri­als pub­lished by the author does not guar­an­tee pass­ing the NABCEP Exam or BPI exam. The author has made rea­son­able efforts to pro­vide cur­rent and accu­rate infor­ma­tion to his read­ers.  The author will not be held liable for any unin­ten­tional errors or omis­sions that may be found