Energy Efficiency Evaluation and Planning for Existing Buildings
For meeting Federal sustainability requirements, agencies can use evaluation methods—such as benchmarking and energy audits—and planning to make their existing buildings energy efficient. To comply with energy reduction requirements agencies should follow a few basic steps:
This is a cyclical process that will need to be continually updated.
For meeting water use reduction requirements in buildings, see Water Efficiency.
The first step in managing a building stock's sustainability is to benchmark buildings. Benchmarking allows buildings to be compared for energy consumption and performance to determine which building is consuming more energy than it should (i.e., where there are inefficiencies and opportunities for improvement).
The ENERGY STAR Portfolio Manager assists agencies in tracking energy performance in buildings and benchmarking. The tool measures building performance on a scale from 0-100 with 100 being a perfect score for energy performance (ideally a net-zero energy building will receive a score of 100).
Where an agency has metered data or data from advanced metering, this information will prove useful for actual benchmarking and tracking progress towards efficiency. For more information, see Metering.
Benchmarking tools are available from the following:
- ENERGY STAR Portfolio Manager
- Oak Ridge National Laboratory Benchmarking Calculator
- U.S. Department of Energy Commercial Building Initiative
Conduct Energy Audits
Once the building portfolio has been benchmarked, buildings can be selected to prioritize for energy audits. Covered facilities much be evaluated for energy improvements each year. At least 25% of facilities covered by EISA 2007 requirements need to be audited each year, so that every facility is evaluated once every four years.
Energy audits should be an ASHRAE Level II type of evaluation and energy efficiency measures need to be identified and implemented by the agency. It is allowable to bundle individual measures into one project for financial and timing purposes. Audits may be conducted by subcontracting services or by training on-site staff through programs or FEMP trainings. Common energy efficiency and water conservation measures include:
- Programming occupancy settings and adjusting controls on HVAC equipment
- Recommission or retro-commission HVAC equipment
- Upgrade older, inefficient equipment that needs to be replaced with more efficient models
- Upgrade lighting fixtures and ballasts
- Install daylighting controls and/or occupancy sensors
- Maintain and operate equipment to its highest efficiency levels
- Replace older, less efficient water fixtures with more efficient models
- Use native vegetation in landscaping to reduce the need for irrigation
- Where allowable, use greywater systems or rainwater harvesting for irrigation, etc.
Once an audit occurs, an action plan should be developed to make certain there is a scheduled approach to integrating conservation measures.
Create an Action Plan
An action plan is an organized compilation of the energy and water conservation measures identified in an audit that allow an agency to implement such measures. The action planning process creates an integrated approach to prioritizing and planning for future improvements. Where buildings are being upgraded or new construction is occurring the measures that have been identified should be integrated at the time of the planned work. See Table 1 for an example of an action plan.
|Table 1. Example of a Federal Agency Action Plan|
|Activity||Location||Planned Date of Implementation||Responsible Party||Status||Funding Allocation||Savings Identified|
|Replace boilers with high efficiency, Energy Star rated boilers||Bldg 2,7,16||April 2013||D. Peterson||Identifying vendor and boiler models||$1.2 Million||~1,500,000 kWh/year|
|Install VFDs in boiler house and on pumps||Bldg 2,7,16 and WWT station||June 2013||D. Peterson||Identifying vendor and VFD models||$250,000||~27,000 kWh/year|
|Upgrade ballasts and install T-5 fluorescent lamps||Bldg 3,9,16, WWT station and guard station||June 2013||H.Smith||In progress||$570,000||~10,000 kWh/year|
|Install Water Sense labeled toilets, urinals and low-flow faucets||Bathrooms on floors 3-7 in Bldg 2; Bathrooms on all floors in Bldg 4 and 5||January 2013||J. Stephens||On hold||$500,000||~50,000 gallons/year|
Typically, an action plan should be created, and then reviewed by a dedicated team of facilities managers and staff from financial departments. The plan should be signed off or approved by senior management, such as a Senior Sustainability Officer (SSO) or site sustainability manager to provide a stamp of commitment to the projects identified.
Once an action plan has been developed, approved and implementation has begun, an agency should plan on monitoring the progress and savings associated with each measure. Collecting data on a monthly basis is ideal for energy and water savings; however an annual assessment should be conducted at the very least. It is common for equipment to be installed and for some adjustments to be needed to create optimum savings. However, without performance monitoring the need for adjustments may go unnoticed and the maximum savings are not achieved. A monitoring program should be implemented to collect data, track energy and water consumption and modify equipment settings or behavior as needed within buildings or a campus.
For technical assistance from FEMP, contact Sarah Jensen.