Photovoltaic Power Plant-CPFL Energia

On Tuesday we visited CPFL Energia in Campinas, Brazil.  CPFL Energia is the largest privately owned power generation company in the country.

Panel Pose-Outside the Control Room of the Power Station

Antonio Roberto Donadon (Innovative Technology Analyst and Director of Innovative Strategy) did an exceptional job of presenting both general information and in depth technical detail.  One interesting tidbit he shared with us was the concept of integrating solar power with wind power.  This is based on the idea that windy days are usually cloudy and sunny days are rarely windy.  So, one technology can compensate for the other when conditions are less than optimal (ex. wind power generation on cloudy days).

The photovoltaic plant we visited had an experimental aspect to it.  There were two types of panels being compared; amorphous silicon and polycrystalline silicon.  The amorphous configuration has a 9% conversion rate, while the polycrystalline silicon modules achieve about 15%.  However, the benefit to using amorphous silicon plates is consistency; polycrystalline models do not perform as well in very high temperature weather.  Overall, Donadon’s conviction was that the polycrystalline version is the most beneficial.

The panels also have two types of configurations.  There are stationary mountings that are always at the same angle, and tracking system mountings that follow the path of the sun from east to west.  In Donadon’s opinion, the tracking system is well worth extra investment and operation costs in terms of energy output. Several rows of solar panels are all rotated by a single (US Manufactured) motor, no larger than a lab scale vacuum pump.  This was a really impressive innovative feature.

Motor for the Tracking System Mounts

Donadon also provided us with some economic information regarding supply chain in Brazil.  The panels themselves are imported from China because Brazil does not currently have the manufacturing capacity necessary to meet their demands.  Unfortunately, importing these panels incurs huge import tariffs for the company.  It would be encouraging to see Brazil expand its solar panel production capacity within the next five years.