Case Study - La Posada


La Posada is a 25 year old, not-for-profit, continuing care retirement community located among the lush Pecan Groves of Green Valley, Arizona. La Posada is the largest senior service provider in Southern Arizona, servicing over 700 residents utilizing a total of 477 independent living apartments, townhomes, and individual residences, 85 assisted living suites, 29 memory care and 58 skilled nursing care suites. The continuing care campus was founded in 1987 as part of Tucson Medical Center’s vision to bring needed programs and services to the senior residents of Green Valley located south of Tucson. In 1997, La Posada became an independent continuing care community.

The 100-acre campus includes resort-style amenities, from swimming pools to hiking trails, and in 2010, La Posada added a retail component. The campus requires the skills of 540 full-time employees to maintain, manage and service the residents of the community.

La Posada was the first Arizona retirement community to receive national accreditation and has received many awards that showcase its dedication to resident care, including ‘Best Practice’ award for Social Accountability and ‘Award of Honor’ for Exceptional Service and Leadership in the field of senior housing, long-term care and aging services.


In 2011, La Posada made a decision to find a renewable energy solution that aligned with the campus’ sustainability initiatives and provided a hedge against rising energy costs. The company was motivated by its residents’ desire for greener lifestyle options as well as its growing gas and electric expenses. Since the community uses over 15,000 gallons of hot water every day for their showers, cleaning, laundry, dining hall and fitness center, the executive and engineering teams were especially interested in finding a renewable solution that would offset their natural gas usage in addition to electricity.


In its search for a solution that respected campus aesthetics, provided a reasonable return on investment, and brought in financial benefits as well as marketing cache to the residents of the community, La Posada considered several renewable alternatives, from wind generation to blanketing the campus with photovoltaic panels. The winning technology for the laundry and fitness center was Cogenra Solar’s solar cogeneration technology selected for its efficiency and quick payback. Solar cogeneration combines traditional photovoltaic (PV) and Solar Hot Water technologies in one unit, providing customers with more energy per square footage and faster payback than standalone PV or solar hot water systems.

Working together with Technicians for Sustainability (TFS), a Tucson-based, locally owned solar installer, Cogenra Solar conducted a site and efficiency analysis of La Posada’s Fitness Pavilion and centralized laundry, two buildings with the highest hot water usages on campus. Buildings’ electricity and hot water usage called for 24 SunPack® modules at the fitness center and 60 SunPack® modules at the laundry facility. Together, both ground-mounted installations take up less than 6,400 square feet, combining the solar cogeneration modules, an inverter, hydronics, and controller in one turnkey, plug-and-play solution.

In about six weeks, Cogenra Solar and TFS designed and installed both systems, totaling 211 kW, with an electric capacity of 36 kW and thermal capacity of 175 kW. Hot water, heated to about 158°F (70°C), is used for the residence’s laundry facility and for pool heating inside the Fitness Pavilion. The electricity generated feeds directly to the community’s existing power supply to support amenities such as lighting, exercise equipment and other electric uses. Access to 24/7 monitoring and performance diagnostics provides La Posada with insight into not only their renewable energy generation but also the financial savings created by the system.


By implementing the solar cogeneration solution, La Posada is able to offset close to 70 percent of their energy use required by the fitness and laundry buildings. Together, the systems displace about 41,858 kilowatt-hours and 11,057 therms of natural gas annually. Solar cogeneration’s unique hybrid of PV and solar hot water qualifies the installation for both solar electric and solar thermal rebates and incentives, which significantly shortens the payback period to less than 5 years.

In addition to saving on energy bills and hedging against future price increases, the retirement community will also reduce their greenhouse gas emissions by 135 metric tons each year. This translates to removing almost 15,100 gallons of automobile gasoline and saving 3,500 trees annually.

This move highlights the company’s dedication to its residents and to the environment. The financial savings generated by the system serve as yet another reminder that businesses don’t have to choose between improving their bottom line and the environment – La Posada is proof that it is possible to do both.