An Energy Conservation Measure (ECM) is proposed to improve the energy efficiency of building infrastructure, including heating/cooling/ventilation systems, utility systems, roof, and windows by replacement and/or upgradation of the existing systems in a cost-effective manner. cove.tool makes running an ECM analysis completely automated and instantaneous. This article shows how you can run an ECM analysis for your project now.
Example Project Description:
The example project is a large office building prototype described by Pacific National Northwest Laboratory (PNNL). Some of the building parameters are mentioned below:
|Project Location||Denver, Colorado (ASHRAE Climate Zone 5B)|
|Total Area of the Building (Sqft)||498,600|
|Total Roof Area (Sqft)||38353|
|Number of Floors||12 (plus basement)|
|Window Fraction||40% of above-grade walls|
|Thermal Zoning||Single Zone Model|
|Floor to Floor Height (Ft)||13|
|HVAC System Type||VAV terminal box / Gas-fired boiler / Water-source|
DX Cooling Coil
|Thermostat Setpoint||75°F Cooling/70°F Heating|
|Thermostat Setback||85°F Cooling/60°F Heating|
|Lighting Power Density (LPD) (W/Sqft)||0.82|
|Equipment Power Density (W/Sqft)||0.75|
|Heating System COP||0.9|
|Cooling System COP||4|
Following are some of the ECM examples that can be modeled in Cove.tool to evaluate their impact on energy performance of the example project described above. These examples just represent the tip of the ice-berg in terms of the analysis potential that cove.tool offers to it’s users.
- Upgrading Roof Insulation:
The roof insulation value can be edited in cove.tool via ‘Baseline Energy’ à Engineering Inputs (Envelope) >> Roof R-Value. In order to see the energy impact of an ECM, a user can modify the value in engineering inputs and hit recalculate. The user will be able to record the impact on the EUI difference in real time. The default roof R-value (based on local energy code) is modified from 30 to 45 to record the impact of enhanced roof insulation.
- Upgrading the Wall Insulation:
The wall insulation value can be edited in cove.tool via ‘Baseline Energy’ à Engineering Inputs (Envelope) >> Wall R-Value. The default wall R-value is modified from 18.1 to 25 to record the impact of enhanced wall insulation.
- Upgrading the HVAC System:
The HVAC System type can be edited in cove.tool via ‘Baseline Energy’ >> Engineering Inputs (Building System) >> System Type. Cove.tool will automatically adjust the heating and cooling COP values once the user selects the system type. The COP values can be easily edited as desired. The default HVAC system of VAV/Water Cooled Chiller/Gas Boiler is changed to VAV/ Ground Source Heat Pump to see the impact of system type on the EUI.
- Upgrading the Lighting System:
A) Changing the Lighting Power Density (LPD):
The lighting power density can be edited in cove.tool via ‘Baseline Energy’ >> Engineering Inputs (Usage and Schedules) >> Lighting (W/ft2) and Lighting (Unoccupied Hours) (W/ft2). The default value of 0.82/0.15 for occupied/unoccupied time is changed to 0.6/0.0 to see the impact on overall lighting load.
B) Installing the Daylighting and Occupancy Sensors:
The sensors setting can be edited in cove.tool via ‘Baseline Energy’ à Engineering Inputs (Usage and Schedules) à Daylight Sensors and Occupancy Sensors. The default value of partial sensors/no sensors was changed to sensors/sensors for Daylight and Occupancy Sensors respectively.
- Installing the Solar Panels:
The solar panel installation settings can be edited in cove.tool via ‘Baseline Energy’ à Engineering Inputs (Energy Generation) à Solar Panel Surface Area, Solar Panel Angle, Solar Panel Module Location and Solar Panel Module Type. The default values of 0/0 for Solar Panel Surface Area and Solar Panel Angle are changed to 3000/45.
Cost vs. Optimization and ECM Analysis:
Although energy conservation measures can be implemented one at a time, the true potential of the strategies can be seen holistically as part of the cost vs energy optimization. The feasibility of any ECM implementation is highly dependent on the capital of the ECM and Return on Investment (ROI). With cove.tool, it is easy to calculate the return on investment if the capital cost for the ECMs is known. The main reason being the consideration of the cost as one of the parameter for the analysis.
The user can list the ECMs in the ‘Change Options’ tab provided in cove.tool along with their cost and test them parametrically. With its unique algorithm, cove.tool optimizes for the cost optimal options for the highest energy performance.
After selecting the modification options, the user can keep the default options provided or change it according to the project owner’s requirement to perform the Analysis.
Cove.tool with its unique algorithm will arrange the parametric ECM bundle options from low cost high energy performance to high cost low energy performance. The cheapest bundle with highest performance can be seen from the following figure.
The parallel coordinate graph shows the parametric ECM analysis.