Pre-Design

Follow the guidelines on identifying energy-efficiency strategies to achieve the owner’s energy efficiency goals per the Owner’s Project Requirements, developed for EAp1: Fundamental Commissioning.

The model you need to develop for EAc1 is the same as for EAp2 unless you’re on a district energy system.

Some energy-modeling software tools have a daylight-modeling capability. Using the same model for both energy and EQc8.1: Daylight and Views—Daylight can greatly reduce the cost of your modeling efforts.

Besides energy modeling, you may need to use the exceptional calculation methodology (ECM) when any of the following situations occur: 

The energy model itself will not account for any change in plug loads from the baseline case, even if your project is making a conscious effort to purchase Energy Star or other efficient equipment. Any improvement made in plug loads must be documented separately, using the exceptional calculation methodology (ECM), as described in ASHRAE 90.1-2004.

LEED divides energy-using systems into two categories:

Projects generating renewable energy onsite should use Option 1 to best demonstrate EAp2 compliance and maximize points under EAc1. Other options are possible but won’t provide as much benefit.

For existing buildings, the baseline energy model can reflect the pre-renovation features rather than a minimally ASHRAE-compliant building. This will help you achieve additional savings in comparison with the baseline.

Energy modeling can inform your project team from the start of design. Early on, review site climate data—such as temperature, humidity and wind, available from most energy software—as a team. Evaluate the site context and the microclimate, noting the effects of neighboring buildings, bodies of water, and vegetation. Estimate the distribution of energy across major end uses (such as space heating and cooling, lighting, plug loads, hot water, and any additional energy uses), targeting high-energy-use areas to focus on during design.  

Use simple computer tools like SketchUp and Green Building Studio that are now available with energy analysis plug-ins to generate a first-order estimate of building energy use within a climate context and to identify a design direction. Note that you may need to refer to different software may not be the one used to develop complete the whole building energy simulations necessary for LEED certification.