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Re: Selling energy via the grid



Mr. Nice Guy <rcanders@nyx10.cs.du.edu> wrote:
>will1000@ix.netcom.com (Will Stewart ) wrote:
>>In <DF15qr.E6D@eskimo.com> lajoie@eskimo.com (Stephen Lajoie) writes: 

>>...Today's converters no longer create a square wave, but a sine wave.

>No they don't produce a true sine wave, they produce a digital 
>approximation of a sine wave with additional higher harmonics.

I think that's true.

>If a user intends to sell power back to the grid they will have to 
>purchase a larger inverter than they would otherwise have needed, 

I think that's false. What do you mean by that? "Synchronous inverters"
connected to the grid can be a lot simpler and cheaper than stand-alone
inverters. Think of a backwards lamp dimmer, with a full wave triac bridge
in series with a choke, with the triacs triggering on for part of the
60 Hz cycle, when the DC source voltage is effectively at a higher
potential than the line. To vary the power delivered, vary the firing
angle. Pretty simple. These don't even need a 60 Hz frequency reference
That can come from the line. 

>inverters are expensive.  The big question is why anyone with 
>access to the grid would select solar power in the first place?

For fun, I guess. And to avoid having a houseful of batteries.

Nick