Glossary of Commercial Building Terms
Auditing
An energy audit is an assessment of a building’s energy consumption by inspecting its systems and operations, insulation and other factors that contribute to energy use. The results of an audit give a building operator a clear picture of how the building consumes energy, where any problems may lie and opportunities for improvement.
Benchmarking
Information and transparency are two of the most important factors when promoting energy efficiency. Benchmarking is the process where building owners and operators use a tool, such as the EPA’s Portfolio Manager, to not only measure their building’s energy and water use, but also to track it over time in order to account for efficiency upgrades in future scores.
Building Energy Codes
Building energy codes require that new buildings and building alterations meet certain minimum standards for energy related features (e.g., insulation, windows, duct characteristics, commercial lighting). For the United States, separate model building energy codes are developed for residential and commercial buildings by standards-making organizations through a stakeholder process in, typically, three-year cycles. States, and sometimes local governments, then adopt the codes into law. Implementation and enforcement is mostly a local responsibility. The Department of Energy encourages, assists and assesses code development, adoption and, to some degree, compliance. There also are standards for federal buildings.
After years of little change, the last two code cycles have seen roughly 30% savings in both residential and commercial codes. Thus increasing adoption of and compliance with these codes are major issues.Much greater savings may require a shift toward performance-based codes (i.e., based on whole-building energy modeling rather than prescriptive criteria for each product) or even outcome-based codes (based on actual building performance rather than estimated performance from the design).
Commissioning, Retrocommissioning and Recommissioning
- Commissioning is a quality assurance process applied across the design and construction stages to assure that new buildings will operate efficiently in accord with the owners’ intent and design specifications, and that building operators are prepared to properly operate and maintain the buildings’ equipment and systems. Commissioning practitioners work with owners, designers, engineers, construction contractors and building operators to verify proper installation and performance of systems as well as to assure that systems documentation and training are provided to building staff so they can properly perform operations and maintenance (O&M). Commissioning also brings a holistic perspective to the design and construction process to better integrate building systems and enhance efficiency and performance.
- Retrocommissioning is the commissioning process applied to existing building. Systems are inspected, tested and adjusted to ensure that they are functioning at optimal performance. The retrocommissioning process seeks to restore building performance to original design intent or to optimize performance in light of building alterations and changes in use since original construction. Low-cost improvements, fine-tuning current systems, and enhanced O&M processes are emphasized instead of major equipment changes.
- Recommissioning is the commissioning of a building that had been commissioned previously. Typically building performance degrades over time after commissioning has occurred. Recommissioning may be triggered by operational problems or changes in use or ownership. Ideally, periodic recommissioning should be part of a building’s overall long-term operational plan so as to restore building performance and efficiency. New monitoring and control technologies are enabling ongoing or monitoring-based commissioning that would allow building operators to tune and calibrate building systems on an ongoing basis.
Disclosure
To increase transparency, energy performance measurements are disclosed to the public to ensure that potential tenants and other interested parties can make informed decisions on where to locate their operations. Disclosure also allows for more comprehensive benchmarking of energy performance.
Energy Aligned Leases
A lease that is “energy aligned” contains language that tries to solve the split incentive problem. While there is no consensus definition for an energy aligned lease and a broad range of language could be used to address the barriers, certain guidelines have been written. For example, as a part of its Greener Greater Buildings Plan, New York City created a task force of building owners, tenants, property managers, lawyers and engineers to craft model lease language, some of which was used in the first ever energy aligned lease signed by Winter Hall law firm in New York City. The language essentially addresses cost sharing for the installment of any efficiency upgrades and ensures that the savings are realized by both landlord and tenant.
Split Incentive
A split incentive often occurs between landlords and tenants in both commercial and residential buildings when trying to implement efficiency upgrades. This problem presents itself differently with various types of leases. In some leases, there is little to no financial incentive for a landlord to install more energy efficient appliances, windows, or insulation because they are not paying the energy bill, the tenant is. Therefore, assuming the landlord even has the capital to invest in these upgrades, he would have difficulty recouping the money earned through energy savings and is therefore unlikely to make this investment.
Sub-Metering
Cities have been implementing policies or incentives for sub-metering in order to enhance the level of information that tenants receive about their energy use. Normally building owners receive a bill for the total amount of energy that the building is consuming and divide this among tenants based on the square footage they occupy. Under sub-metering policies, meters are installed by floor or by tenant occupancy, which allows the tenant and/or the building owner to see how much energy each unit is consuming. This can prove difficult as many spaces change with each new tenant, so some laws only require spaces above a certain size to be sub-metered or owners to meter the entire building floor-by-floor. In an ideal circumstance, contracts would stipulate that tenants pay for however much energy they use, encouraging them to make behavioral or other changes. If this is not the case, the building owner can still see which tenants are using the most energy, discover why that is the case and try to implement energy conserving changes.
Sub-metering for electricity use is most common, but it can be a useful tool for water and heat as well.
This becomes even more difficult in other leases where tenants pay energy bills directly to the landlord on a per square foot basis and the charge is static. Due to fluctuations in energy prices, landlords actually stand to make a profit off of a tenant’s energy bill. Thus, they do not want to spend this money on efficiency upgrades and have to charge less for utility bills.
On the tenant side, many occupants do not want to invest in efficiency upgrades because they are unsure if they will be staying in their rental for a long enough period of time to receive payback, and therefore believe the landlords should be making these upgrades.
