Small buildings with few electrical demands are prime targets for stand- alone solar power units. That’s thethought behind new solar technologyapplied to a bus shelter on the campusof McMaster University in Hamilton,Ontario, Canada. The flexible solar designwas developed by a group of researchersat the school.
Silicon solar cells were custom-fabricatedfor this purpose and mounted on a sheet offlexible material. Much of the developmentwork went into the method of connectingthe cells “reliably and effectively,” according to Adrian Kitai, a professor on thefaculty of engineering. The result is twoflexible strips, each measuring 90 ; 12 cmand comprising 720 solar cells measuring1 ; 1 cm each. Each strip can generate upto 4. 5 W of power. The energy generatedduring the day is stored in batteries tolight the shelter for eight hours at night.
Each of the two LED fixtures that light
the shelter uses 600 m W of power and
produces about the same light output as a
3-W regular tungsten bulb – equivalent toa small night-light. The solar power instorage is more than enough to run the twolights throughout the night, so even if it’sa cloudy day or there’s snow on the roof,backup power is there, Kitai explained.
He added, though, that the researchers
have not yet made observations with 2 ft
of snow on the roof, so they are not sure
what the results of such long-term shading
Building on their experience with
flexible solar design, the McMaster team
members are building integrated projects,
anticipating commercial success in the
not-too-distant future. ;
Flexible solar from Canada
Researchers at McMasterUniversity in Ontario developedflexible strips of silicon solar cellsthat have been used to powerLED fixtures in a bus shelter.