La Posada, a retirement community in Tucson, Ariz., is installing a hybrid solar hot-water photovoltaic (PV) system by Cogenra. It’s just the latest in a number of green moves the retirement community’s made, including building net-zero energy homes for retirees. The Cogenra system will help residents fully enjoy the benefits of solar power—after all, it’s being installed at the community’s fitness center and spa.

It’s not the first time La Posada has installed solar on the campus. And residents approve of the efforts.

“While there has been no formal vote, there has been a clear voice on the desire to maintain green technologies, low water use applications and solar technology to lower operational costs,” said La Posada Vice President of Marketing Tim Carmichael.

Earlier this year, La Posada announced that it would start offering net-zero energy homes in it’s Park Centre Homes division of the retirement community.

“The homes will utilize a Net Zero photovoltaic system with the potential to reduce energy costs by more than 85 percent,” the company said in a March 2011 release.

“Park Centre Homes [is] a 35-home energy efficient neighborhood. Currently there are 20 of the homes on campus. Through design and the use of PV, the community is able to obtain substantial energy savings,” Carmichael said.

Each of the homes in Park Centre has a 3.14-kilowatt photovoltaic array, according to a press release. But the Congenra system at the spa and fitness center will be larger, bringing the amount of installed solar at the center up.

“The combined systems will total up to 300 kilowatts [estimated]. The details of each installation will be announced shortly upon project completion,” Carmichael said.

Cogenra’s unique solar product, the SunDeck, uses a trough-type technology to focus sunlight on a row of photovoltaics, increasing the amount of light and heat that hits each cell. The photovoltaics are connected to a heat sink, which is connected to liquid-filled tubes. The heat from the panels is transferred to the liquid in the tubes, which is cycled to a heat exchanger, which is then used to heat water for use on premises.

Since the solar cells are kept cooler, they also operate more efficiently. The company said the device can get roughly four times the energy from the sun than conventional photovoltaics can get.

At this point, the Cogenra SunDecks are being installed only outside La Posada's fitness pavilion and laundry facility, according to Carmichael.

“They are also negotiating additional installations, e.g. for residential apartment complexes,” he said.