Integrated Whole-Building Zero Net Energy Retrofits for Small Commercial Offices

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Small commercial offices experience a number of unique barriers to achieving substantial energy reductions including: 1) a lack of awareness of and access to cost-evaluative information about how to achieve energy targets, and 2) affordable access to services such as engineering and audits. Existing tools and services currently involve higher costs when applied to small commercial buildings due to the lower amount of energy cost savings realizable on a per-square-foot basis. Small commercial buildings are consequently disadvantaged in accessing the same detailed retrofit information that larger buildings can gain cost effectively.
This project developed cost-effective retrofit packages to achieve zero net energy and/or zero carbon performance for California multi-story small commercial offices (<50,000 sf). The packages target 50 percent energy savings, with costs within 10 percent of conventional construction costs, and internal rates of return of 5 percent or more within 10 years. The developed retrofit packages have been validated for energy performance, visual and thermal comfort, under controlled laboratory test conditions and demonstrated in a small commercial building (City of Berkeley Mental Health Services facility). Energy measures were also built into an online public tool, the Commercial Building Energy Saver (, to enable small commercial facilities to conduct zero net energy retrofit assessments, providing cost-evaluative metrics.

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