High Performing Buildings - Winter 2011 - (Page 58)

TA B l e 1 s i M P L e P v P a y B a C K a n a Ly s i s $85,000 ($25,500) ($13,000) ($37,600) ($8,200) first Cost of 11 kW Pv system federal tax Credit state tax Credit solar renewable energy Credits income — eight years energy income — eight years LessOns Learned aim higher. When the goals were set, no leed gold office buildings were located in Kentucky. Pursuing leed gold seemed doable at the time, and the building was awarded leed gold by the u.s. green Building Council in october 2009. The project was submitted under new Construction Version 2.2 and was awarded 49 points. The minimum number of points required for gold is 39, and Platinum is awarded at 52. on a traditional project, the meP firm submits only the meP related points, but this building provided a crosstraining opportunity. firm engineers collaborated with the architect and contractor to submit all points. The goal should have been Platinum. leed gold certification was exceeded by 10 points and Platinum was missed by three points. Platinum could have been obtained with minimal extra cost if two missed points had been documented correctly. four other credits could have been reasonably pursued if prioritized early, including Certified Wood, low-emitting materials, indoor Pollutant Control and enhanced Commissioning. Leed can be obtained in a timely manner. CmTA has been a team member on projects in which the leed submittal process took too long, frustrating clients. submitting the design credits during construction speeds the process. many teams that CmTA has worked with prefer to submit all at once, which slows the process. The construction points for the CmTA headquarters were awarded four months after project completion. This allowed CmTA to combine a grand opening with the leed ceremony. the cost for Leed gold did not impact the budget as significantly as clients typically fear. silver could have been obtained for less than a 1% premium. The cost for all points and increased fees was $186,000 or 5.8% of construction cost. However enough points for leed gold could have been obtained without the PV system and demand control ventilation system, which reduces the added cost to $81,000 or 2.7% of the total cost. elective features are included in almost every project. CmTA likes to compare the cost of leed gold to its open stair, an elective architectural feature. The building can operate without it, but is a beautiful architectural element in the lobby. The open stair affected the project budget comparably with the cost to obtain leed gold. thinking about high performance design as an affordable option is a big change for many clients, and change can be difficult. Clients find it helpful to take tours of the various sustainable projects that the firm has completed so they can see how the high performance systems function. They have an opportunity to speak with the owner about energy performance, maintenance requirements and construction cost. some clients have never seen a geothermal system, touched a solar photovoltaic panel or walked through a daylit room. They can review copies of the actual utility invoices or the financial model of the PV system at CmTA’s headquarters building. They can sit at the ddC user interface to witness real-time system performance such as geothermal temperatures, building Co2 levels or the heat recovery provided by the energy wheel in the doAs unit. complexity. Firm engineers concentrated on the occupied/unoccupied operation of the geothermal system, unoccupied control of plug loads and proper operation of the lighting control system. The geothermal heat pump units are scheduled to operate from 7 a.m. to 5:30 p.m., Monday through Friday. They maintain a 60°F setpoint during winter unoccupied hours. Trending of unoccupied runtime hours shows that only a couple of zones ever operate because of the high quality thermal envelope. in the summer the heat pump units are always off during unoccupied periods. Occupied temperature setpoints are 72°F, summer and 73.5°F, winter. Occupants can adjust temperature within a range of ±2°F. employees working outside of the regular hours can adjust thermostat settings by using the override button, which resets a control zone’s setpoint to the occupied mode for two hours. Control of plug loads was considered during design. The power to printers, plotters, vending and the coffee maker is deactivated on the same occupancy schedule as the hVAC system. This eliminates some of the phantom plug loads. A 30-minute override button is provided to allow operation during unoccupied hours. hindsight shows the elevator should have been on a similar schedule because it is consuming a significant phantom load 24/7 and is rarely used. Staff is asked to turn off workstations at night. The “computer police” periodically check workstations after hours to help change past routines into new habits. 58 HigH Performing Buildings Winter 2011

Table of Contents for the Digital Edition of High Performing Buildings - Winter 2011

High Performing Buildings - Winter 2011
Commentary
Contents
Portland State's Shattuck Hall
Oberlin College's Adam Joseph Lewis Center
Dell Children's Medical Center
CMTA Office Building
EPA Region 8 Headquarters
Honda's East Liberty, Marysville Auto Plants
Advertisers Index

High Performing Buildings - Winter 2011