Payback using U.S. Green Building Council (USGBC) cost data and industry standards developed by the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE).

Level	Cost	Energy Savings	payback
Certified:	0.66%	18%	1.5 yrs
Silver:	2.11%	30%	4.2 yrs
Gold:	1.82%	37%	3.2 yrs.
Platinum:	6.50%	28%

Source: www.wgba.org

Feature	Payback
Fluorescent Lighting	≤3 yrs
Solid Building Envelope (Insulation, ...)	2-3 yrs
Green Roofs (garden)	4-13 yrs
Geothermal Heat Pump	8-12 yrs
Photovoltaic Panels (PV)	10+ yrs *

Source: Architect Magazine

Costs: $3-5/sq. ft.
* With 70% rebates in New Jersey the payback could be a low as 5-7 years, depending on your electrical bill acording to Mike Strizki of Advanced Solar Products.
Mass. has a 50% rebate.
According to a article in the Home News Tribune, 04/22/07 a 34 solar panel system in an Edison house cost $40,000 ($11,000 after rebates) in 2004 and the owner expects to break even in 7 years.
2-4 kW systems good for the average house can be installed for as low as $15-28,000.
Panels last from 25-40 years.

The Leadership in Energy and Environmental Design (LEED) Green Building Rating System ™ is the nationally accepted benchmark for the design, construction, and operation of high performance green buildings. It ws developed by the U.S. Green Building Council.
The Rating system for new homes includes an assessment checklist.

The National Association of Home Builders has recently published NAHB Model Green Home Building Guidelines.

The American Institute of Architects' Committee on the Environment has a Ecological Literacy in Architecture Education.

Green Building Industry Portals:
Whole Building Design Guide (www.wbdg.org/, www.buildinggreen.com/, http://www.greenbuilding.com
and Sustainable Sources www.greenbuilder.com

The U.S. Federal government has also been moving toward the adoption of green building practaices, as detailed in a recent report by the Office of the Federal Environmental Executive - www.ofee.gov/sb/fgb_report.html
Other Federal Programs:
The Dept. of Energy's Building Technologies www.eere.energy.gov/buildings/
The EPA's Energy Star rating program www.energystar.gov
and th GSA's Sustainaable Design program www.gsa.golv/Portal/gsa/ep/caelView.do?pageTypeID=8195&channelID=-12894

Problems:

• The cost of solar panels will not drop precipitously like some other technologies. One reason is the scarsity of silicon needed to manufacture them.
• Hydrogen danger of explosion:
  It is very difficult, in fact, for hydrogen to accumulate anywhere because it diffuses so rapidly. It is lighter than air so goes up rather than down like natural gas.

Some Green Buildings:
Bullitt Center, Seattle WA
Tahoe Center for Environmental Sciences | Tahoe Environmental Research Center - UC Davis - Incline Village, NV
Duke Farms - Orientation Center LEED Platinum - Hillsborough, N.J.

Books:
"The Hype About Hydrogen: Fact and Fiction in the Race to Save the Climate,", Joseph J. Romm

LINKS:
U.S. Green Building Council
GreenBiz.com - payback 3-5 yrs.
U.S. Green Building Council (USGBC)
  Leadership in Energy and Environmental Design (LEED) program at USGBC
Building Technology Options For Your New Home at Nebraska Public Power District
the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE)
New York City Enacts Broad Green Building Law for Its Projects - payback 7 yrs.
Home Insulation

Heating

Sensors Data Logger / Controllers at: onsetcomp.com/ Home Automation
Home Automation Page and Home Automation Products here