Zero Energy Buildings: When do they pay off in a hot and humid climate?
Major Findings of the ‘Hot and Humid’ Zero Energy Buildings (ZEB) Study:
1. Designing buildings for zero energy use in hot and humid climates like that of the Gulf Coast of Texas can be a good investment in the context of a 25-year lifetime of the building.
2. Investing in energy-efficiency measures, even extreme energy-efficiency measures required to make a building “net-zero energy ready,” can become profitable within 9-13 years for a broad selection of building types, making this a potentially attractive investment for a wide range of building owners and developers.
3. The net present value (NPV) for larger buildings at 25 years was significantly higher than for smaller ones. Large buildings apparently benefit from economies of scale in the purchase of solar panels and less commonly specified HVAC system components.
4. The greater upfront investment required for larger buildings also tends to result in much higher rates of return than for smaller buildings.