Las Pintas project

Harnessing the power of the sun

You might say that Dan Eberle got into hot water when he and a group of six students visited Mexico this spring.

The assistant professor of energy performance and resource management and his students designed a solar-powered water-heating system that brings hot water into homes in the Santa Rosa neighborhood of Las Pintas, Mexico, located on the outskirts of Guadalajara.

Many of the homes in the community have only limited access to hot water, Eberle said. Some residents use immersion heaters like those used in stock tanks to heat water; others use a butane heater.

However, those methods can cost as much as 50 cents a day, a huge bite out of the budget when the average weekly income is less than $100 per week.

What Las Pintas has in abundance is sunshine, and Eberle and his students harnessed the power of the sun both to heat water and to power a pump to bring that water into the house.

The challenge, Eberle said, was to create a system that could be built cheaply, using materials that could be salvaged or purchased inexpensively.

His original plan was to build a system of coils that would lay atop a flat roof, absorbing the sun’s heat like a hose left in the sun. The problem was that such a system could only produce about two gallons of hot water in a day, far short of the 20 gallons that Eberle said was needed by a family for personal hygiene, food preparation and washing clothes.

So he and his students devised a different system, one that included pair of barrels: one to hold the water that was being heated on the roof of a house and another to provide weather proofing. It also included a pump powered by small solar panels that put the heated water into a storage tank and then moved it into the home.

The effectiveness of the setup was quickly proven: The group installed the first system one morning, finishing in time for the afternoon siesta. By the time Eberle and his students came back at 5 p.m., the water in the storage tank was ready to use.

“For one adult, that was the first time he’d ever had a hot shower in his home,” Eberle said.

In exchange for the water-heating installation, the five families in the community whose homes now have the system installed have each agreed to recruit five others for a water-heater installation, resulting in an exponential growth of the availability of hot water in homes.

Eberle described it as a dramatic demonstration how just a small input of resources from the JCCC students “planted a seed that would be a real life-changer.”

JCCC has a long term relationship with the community in Las Pintas, sending teams of students, faculty and staff to assist with the community’s health needs since 1998.