Net-zero energy (NZE) buildings are gaining interest from building owners, tenants, and landlords alike due to increased rent rates, net operating income, and resale value for landlords, along with healthier, more productive, and more enticing workspace environments for tenants. Rocky Mountain Institute’s latest action guide, Best Practices for Achieving Zero Energy Over Time for Building Portfolios, provides a roadmap for portfolio owners and managers to achieve cost-effective deep energy retrofits that lead to zero-energy status for their entire portfolio while increasing revenues. 

The zero-over-time (ZOT) approach focuses on cost-effective energy efficiency and renewable energy by prioritizing projects that pay back quickly in the short term, while aligning larger energy efficiency projects with major building life-cycle events, like equipment upgrades. Major life-cycle events can serve as trigger events for energy upgrades, as incremental costs for these upgrades will be lowest. 

RMI’s action guide includes a case study portfolio in Denver that illustrates that taking the ZOT approach can achieve net zero energy over a 20-year period with a net present value (NPV) of added value of $1.3 million over 20 years and $10.3 million over 30 years.