>From the 2006 white paper: "Polarization Incorrect grounding of SunPower modules can induce a surface charge which would lower the energy production. Previously SunPower has announced the
discovery of the "surface polarization" effect which creates a non-destructive and reversible accumulation of static charge on the surface of high-efficiency solar cells such as SunPower's A-300 cells [9]. When the cells have a high positive voltage with respect to ground, a negative static charge is built up on the surface of the cell due to current leakage through the glass and the highly insulating front surface anti-reflection coating of the cell. This negative static charge causes increased surface recombination and the performance of the module is reduced. If the polarity is reversed and the cells are highly negative with respect to ground, the negative static charge is replaced by a positive static charge which restores the module performance." Mark Frye Berkeley Solar Electric Systems 303 Redbud Way Nevada City, CA 95959 (530) 401-8024 <http://www.berkeleysolar.com/> www.berkeleysolar.com _____ From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of jay peltz Sent: Saturday, November 20, 2010 4:30 PM To: al...@positiveenergysolar.com; RE-wrenches Subject: Re: [RE-wrenches] Positive-ground question re Sunpower Hi Allan, I have seen the white paper from Sunpower, ( but don't have a copy) that shows the losses as the voltage rises if using neg ground. But from memory, if using at low voltages such as two in series there should be minimal if any "loss" of watts. If you could use them as singles, for say a 12v system then there is no loss. Jay Peltz power
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