Solar for a Vintage, Multifamily High-Rise: A Tower Companies Case Study

Commercial building owners of older properties may feel challenged when it comes to making energy efficiency improvements and adding renewable energy to their buildings. When most of us picture green buildings, we think of new, gleaming structures with all the latest technology. The fact is, though, the greenest building is one that is already built and operating efficiently. The Tower Companies demonstrates how an older building can be harnessed to generate renewable power and provide a robust financial incentive to the owner.

In 2019, The Tower Companies (“Tower”) installed the largest rooftop solar PV system on a multifamily building in Montgomery County, Maryland. The 122-kW installation reduces almost 10% of the overall operating costs at Blair House, which is just one of their properties located on a 27-acre mixed-use development in which is collectively called “The Blairs”. The building is a 12-story, 310-unit, 375,000-square-foot apartment building located in Silver Spring, Maryland, on the D.C.-Maryland border. It is LEED Gold and ENERGY STAR Certified.

Tower has supported renewable energy projects for over a decade through strategic purchases and on-site solar PV arrays to offset 100% of their portfolio’s carbon footprint. After completing their first on-site solar project in 2014, the Tower Team began to explore options for additional solar projects. Tower identified Blair House as an existing property that had great solar potential. This decision was based on factors including building age, roof age, roof condition, roof size, number of obstructions on the roof, shading, roof offset requirements, proximity to the D.C. feeder lines, access to building drawings, and the overall projected energy savings of the project.

The Tower Companies successfully implemented an internally financed on-site solar project for an older building, without the need to take on external financing partners, by utilizing a combination of energy savings and available local, state and federal incentives. Tower chose to purchase the system outright in lieu of using a third-party financing mechanism. The investment will yield a 100% after-tax payback in the first year and an internal rate of return of 30% over 20 years. Tower was able to achieve a one-year payback on the approximately $350,000 investment by incorporating:

• Annual energy savings from common area electricity usage
• Local solar renewable energy credits (SRECs)
• The Maryland Energy Association (MEA) commercial solar rebates
• The Federal Investment Tax credit which provided 30% for projects completed in 2019 (the value is decreasing over time).

The operational cost savings allows the team to invest in other sustainability projects and amenities for residents, ensure efficient operations, and meet the company’s carbon goals.

The team has also installed a dashboard in the lobby of Blair House for residents and visitors to see the building’s solar generation in real time. Tower is also planning to install a viewing platform on the roof in order to provide tours to the industry and community. Tower has heard from residents that their sustainability commitment was a factor in why they chose to live at The Blairs, and they enjoy being able to see the numbers associated with the solar system.

Tower plans to expand their on-site renewable energy portfolio in the coming years with over 1 MW in the pipeline. The company hopes that sharing its challenges and solutions from this project will lead to greater adoption of onsite renewables for others in the industry.

For more detailed information visit The Better Buildings Solution Center to read more.