| Popis: |
Intelligent use of rural residential land and sustainable construction is inexorably linked to cost; however, options exist that are eco-friendly and have a positive return on investment. In 2011, a research residence was built to evaluate various land-use and sustainable components. This Texas house has subsequently been used for both residential and research purposes. The purpose of this case study was to evaluate break-even construction considerations, to assess environmental impacts, and to evaluate qualitatively efficacy of sustainable options incorporated in the research residence. Some of the specific components discussed are home site placement (directional positioning); materiel acquisition (transportation); wood product minimization; rainwater harvesting; wastewater management; grid-tied solar array power; electric car charging via a solar array; geothermal heating and cooling; insulation selection; windows, fixtures, and appliance selection; and on-demand electric water heaters for guest areas. This study seeks to identify the impact of proper land use and sustainable techniques on the environment and return-on-investment in rural areas. Break-even and 15-year Net Present Value (NPV) analysis at 3% and 5% cost of capital were used to evaluate traditional construction, partially sustainable construction, and fully sustainable construction options for the case study house, which was built sustainably. The additional cost of sustainable construction is estimated at $54,329. At 3%, the analysis suggests a 15-year NPV of $334,355 (traditional) versus $250,339 million (sustainable) for a difference of $84K. At 5% cost of capital, that difference falls to $63K. The total estimated annual difference in carbon emissions is 4.326 million g/CO2e for this research residence. The results indicate that good choices for quick return-on-investment in rural construction would be the use of engineered lumber, Icynene foam, and Energy Star windows and doors. Medium-term options include photovoltaic systems (PVS) capable of powering the home and an electric car. Sustainable construction options should positively affect the environment and the pocketbook. Regulations and code should require adoption of short-range, break-even sustainable solutions in residential construction. |
