High Performing Buildings - Summer 2011 - (Page 62)

© 2008 don f. Wong building in line with anticipated performance, showing a consistent downward trend in energy use that continues to be maintained (see Graph 1). This stands in stark contrast with common building performance in which building performance declines with time as energy usage consistently trends upward. Specific energy reductions due to individual adjustments made in the post-construction period cannot be easily quantified. This is because each adjustment was incremental, and since many were made in the first year of operation, a previous year of fine grain metered data was not available to compare against. Above This view of the north elevation of Great River Energy Headquarters Building includes the wind turbine to the left. In the foreground is the man-made Arbor Lake, which supports the geoexchange heat pump system. The site was formerly a gravel pit. Left The building is designed to take advantage of natural daylight using lightly tinted glazing with specularly selective glass coatings. Multiple glass types and frit patterns were explored through the energy model to find the right balance between solar control and visual clarity. Frit patterns vary on different elevations. g r a P H 1 2 - y e a r e n e r g y u s e C o m pa r i s o n ( k B t u / F t 2) key s us ta i naB l e Features Water Conservation rainwater used to flush toilets, drought-tolerant native landscaping, low-flow fixtures materials fly ash used to replace 45% of Portland cement; forest stewardship Council (fsC) certified wood throughout including formwork; locally sourced agrifiber substrates for all millwork Jun 08 Jul 08 Aug 08 Sep 08 Oct 08 Nov 08 Dec 08 Jan 09 Feb 09 Mar 09 Apr 09 May 09 Jun 09 Jul 09 Aug 09 Sep 09 Oct 09 Nov 09 Dec 09 Jan 10 Feb 10 Mar 10 Apr 10 May 10 Code Actual Proposed (Code = ASHRAE/IESNA Standard 90.1-2004) Daylighting more than 85% of occupied space receives at least 25 footcandles and more than 90% of occupied space has views to the outdoors individual Controls raised access floor with manual control diffusers other major sustainable Features increased ventilation effectiveness using displacement ventilation site was recovered from a previous gravel pit native and adapted landscaping used to restore the site’s limited vegetation cover Post-occupancy commissioning is an important part of bringing green buildings up to their full performance potential. graph 1 shows the performance gap between the anticipated design potential (Proposed) and the built potential (actual) closing after incremental adjustments to the building’s systems were completed by the design and facilities team over the course of about 12 months. as a first step, the building’s trending meters were commissioned to confirm their accuracy. during the ongoing Cx (commissioning) phase, trending data from the meters was compared to the design phase energy model as a way to identify areas for improvement. Targeted adjustments were made primarily to the sequence of operations and to equipment settings to incrementally reduce building energy use while maintaining and improving occupant comfort. during the 12-month measured Performance Period, most adjustments were stopped and trending data was collected monthly. during the final verification phase, the building performance was compared to the utility bills and a calibrated energy model reflecting the real-time weather and operating conditions of the building. all were within 1% of each other. 62 HigH Performing Buildings summer 2011

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

Commentary
Contents
Stanford University's Y2E2
The Christman Building
The Gettysburg National Military Park Museum and Visitor Center
Cannon Design Regional Offices, Power House
Great River Energy Headquarters
Letters
Products
Advertisers Index

High Performing Buildings - Summer 2011