Executive Summary
After studying different proposal options and analyzing the surface water geothermal system, it was concluded that installing a surface water geothermal system to replace AHU R-1 will have a significantly positive impact on the overall design, economics, and energy efficiency of the Potomac Science Center. This alternative design will not only provide the owner with a cost saving system, it will become an important tool that students can study first hand. Due to the lack of significant number of surface water geothermal systems, any successful system can become an attractive selling point.
The alternative design looks to improve on the great design already in place for the Potomac Science Center. The alternative design will swap the central-station air handling unit (AHU R-1) for a surface water geothermal system. In addition to reducing operation and maintenance costs, a simple payback analysis showed that the system will have a payback of 7.5 years. Analysis shows that the system will save the building over $22,000 annually with an 18.4% reduction in emissions. Although the initial cost is high at $186,303 , the federal government offers a 10% Federal Rebate for any geothermal systems that meet the requirements set forth, making the initial cost $167,672.
Based on the life cycle cost data, emissions report, and cost analysis, the alternative proposal is recommended. The payback period allows the owner to return his investment rather quickly.