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The City of Houston is participating in the U.S. Department of Energy’s Better Buildings Challenge, aiming to engage the community in achieving a reduction in energy consumption of at least 20% by 2020 from 2008 levels, across 30 million square feet (ft2 ) of buildings. This includes 7 million ft2 of city-owned buildings. The City is also aiming to attain the highest number of ENERGY STAR1and LEED2 certified buildings in the U.S.

Instead of relying on the power of legislation, the voluntary Houston Green Office Challenge seeks to advance a holistic pursuit of office and building sustainability. This programme officially began in January 2011 as a partnership between the Mayor’s Office of Sustainability in Houston, ICLEI – Local Governments for Sustainability, and the Clinton Climate Initiative.

The Challenge seeks to engage commercial property managers, building owners and office tenants in a friendly, voluntary competition that guides participants towards sustainability and greener building management, whilst recognising outstanding achievement.

The areas targeted by the programme are: energy and water consumption, waste outputs, transportation, building management or tenant engagement, and employee outreach. High achievements are acknowledged through awards, media attention and official mayoral recognition.

What is it?
The Green Office Challenge is a friendly voluntary competition that engages the private sector (commercial building managers and tenants) in improving the environmental performance of their offices and buildings.

How does it work?
The Challenge focuses on commercial buildings (Class A, B and C buildings3), as this sector makes the most significant contribution to community-wide greenhouse gas (GHG) emissions.

The programme welcomes participation from both tenants and property managers or building owners, with different tools and evaluation schemes employed for these groups:

  • Property managers/building owners use the Environmental Protection Agency’s4 ENERGY STAR Portfolio Manager5 and ICLEI’s Green Business Challenge reporting platform. Metrics evaluated by the combination of these two tools include energy and water consumption, waste, and tenant engagement.
  • Tenants are directed to monitor progress only through the Green Office Challenge Tenant Scorecard on ICLEI’s Green Business Challenge platform. This helps participants evaluate their strategies to influence employee behaviour in energy use, waste, transportation choices and outreach. This scorecard creates a baseline score and suggests measures to improve performance. Scores are organised into four tiers of achievement: Tier 1-Platinum (76-100 points), Tier 2-Gold (51-75 points), Tier 3-Silver (26-50 points) and Tier 4-Bronze (15-25 points).

Another key element of the Challenge is education and support from the City, including free training and educational seminars, as well as workshops and webinars. The City also offers recommendations for improving building and office sustainability, assistance in setting up Portfolio Manager accounts, referrals to free energy audits, and financial incentives for energy efficiency retrofits from the City and local energy utilities.

Outstanding performance in the programme is recognised through an awards ceremony hosted by the Mayor and the City of Houston and through extended media coverage.

CO2 reduction
For the first Challenge year, the programme has mobilised a total of 375 buildings and tenants, covering approximately 75 million ft2 of building floor space. City officials have reported the following achievements:

  • Reductions in energy consumption by 28 million kilowatt hours
  • Reductions in water consumption by 280 million litres
  • 90% of participating tenants recycled in the office, achieving a 40% diversion from landfill
  • More than 50% of the participants adopted various sustainability measures such as flextime and telecommuting policies, bicycle parking and policies to reduce paper consumption

The programme provides a great opportunity for knowledge sharing amongst participants. The City believes that this information sharing is assisting the implementation of retrofitting activities and the achievement of higher energy efficiency across buildings in Houston. Furthermore, not all success stories are from Class A buildings, as many have also come from smaller Class B or C types.

The Challenge provides a good example of how voluntary schemes can be used to engage and incentivise building owners, commercial property managers and tenants to reduce the environmental impact of the private sector, with tailored approaches and reporting requirements.

Further information
To find out more about Houston’s Green Office Challenge, the programme’s success factors, challenges and lessons learned please refer to the report Urban Efficiency: A Global Survey of Building Energy Efficiency Policies in Cities launched by the Tokyo Metropolitan Government and C40 in late 2014 and updated in May 2015.


1An ENERGY STAR certification shows that a building performs better than at least 75% of similar buildings in the U.S. Scores are calculated through Portfolio Manager and account for differences in weather variations, building operating conditions and other factors.

2Leadership in Energy & Environmental Design or LEED is a green building certification programme that recognizes top building strategies and practices in design, construction, operation and maintenance.

3According to the Building Owners and Managers Association International (BOMA), Class A buildings are prestigious buildings competing for premier office users, with rent above average, high quality standard and excellent accessibility. Class B buildings compete for a wide range of users with rents in the average range for the area, good building finishes and adequate systems. Class C competes for tenants requiring functional space at rents below the average for the area.

4Environmental Protection Agency or EPA is the federal U.S. agency responsible for protecting and improving human and environmental health.

5Portfolio Manager is a free online tool provided by the U.S. EPA that enables building owners and managers to track and assess energy and water use across their entire portfolio of buildings.

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