For investors interested in energy efficiency in either conventional or green construction, meaningful answers to a few questions will go a long way towards ensuring a sustainable investment.
Is the building among the most energy efficient in the country?
To determine how a building's energy use compares to other similar buildings in the country, the U.S. EPA's ENERGY STAR program developed an energy performance rating system that rates a building's energy efficiency on a scale of 1–100. A building that scores in a 75 or above on this scale (placing its energy performance among the top 25 percent among similar buildings) can earn an ENERGY STAR label. Receiving a rating for a building is easy and can be done at the energystar.gov Web site using Portfolio Manager, a free, online tracking and benchmarking tool.
More than 130,000 have been rated, and more than 12,600 of them have earned the ENERGY STAR label to date.
Has an energy target been established?
New construction project teams often promote building designs that are energy efficient, but do not always provide an estimate of the completed and commissioned building's expected energy to owners and investors. Many green building rating systems and programs targeting energy efficiency in building design rely on computer modeling primarily concerned with estimating if a design exceeds the building code, which is not an indicator of how much energy the building will use.
Establishing energy targets can help drive energy-efficient design choices; energy efficiency goals should be set based on comparisons to actual building energy use. EPA's Target Finder tool provides an easy way to develop an energy use target tailored to a specific design project.
Investors should ask about a new building design's estimated energy use and if it is Designed to Earn the ENERGY STAR.
What method or system was used to certify the building? Did it earn points for energy efficiency?
Because of the flexibility of most green building rating systems, a building with poor energy efficiency can be certified as green. Since energy-related points may not be required by a particular green rating system, it is important to evaluate how the property was rated on energy. Additionally, since green recognition is often given to a building prior to it being fully occupied and commissioned, it is important to determine if the fully-commissioned building has achieved its intended efficiency.
If the building has been operating for at least one year, it should be benchmarked for energy efficiency using the ENERGY STAR Portfolio Manager tool and against its energy target.
Energy-efficient buildings have efficient components and systems that are properly designed and sized and are actively managed once occupied. It is important to make sure that these investments are not subverted in the name of green design or value engineering.
Specifying and installing the latest energy saving technologies may make little impact unless these technologies are properly commissioned along with other building systems. New technologies often require more attention during commissioning. Be sure that the project budget includes proper funding for commissioning.