[RE-wrenches] Xslent?

[Bill Brooks]

Jay and Peter,

Paying extra because of reactive power is not the reason for having this
feature presently. The charges for reactive power are insignificantly small
to the customer. The real reason for reactive support has to do with
utilities beginning to require it as a condition for interconnection. 

While I have heard of a few small systems where reactive power has been
required for small systems (that is quite silly), it is normally associated
with very large PV plants (5-50MW).

The 6kW system outperforming a 10kW system should cause all sane people's BS
meters to peg the limit--that is utterly preposterous without significant
shading. All companies making such unfounded claims, without detailed
qualifying statements to define when the claim would be true, should be
shunned from the PV industry until they behave. Several companies over the
years come to mind with that statement.

Bill.

-----Original Message-----
From: re-wrenches-bounces at lists.re-wrenches.org
[mailto:re-wrenches-bounces at lists.re-wrenches.org] On Behalf Of jay peltz
Sent: Thursday, January 06, 2011 4:43 PM
To: RE-wrenches
Subject: Re: [RE-wrenches] Xslent?

HI Peter,

I agree with you that for now on residential it makes no sense.
However for commercial that might have to pay extra for PF issues, to have
the inverter adjust for this makes sense.
Its the reason they( inverter companies ) are doing it.
I"ve heard a better more complete reason of course from Bill Brooks, who
maybe can chime in.

sorry got away from me,


jay 
peltz power
On Jan 6, 2011, at 2:34 PM, Peter Parrish wrote:

> I can't understand how any inverter WOULDN'T deliver its power with the
> voltage and current 100% IN PHASE. 
> 
> When the voltage and current are not 100% in-phase that represents
reactive
> power. Reactive power flows positive for a quarter of the AC cycle, then
> negative for a quarter of a cycle, then positive and then negative. The
net
> result over one AC cycle is ZERO power delivered to the load.
> 
> So reactive power is worthless. 
> 
> Worse, it results in higher currents (and voltages) for the same amount of
> in-phase power, putting additional stress on circuits.
> 
> - Peter
> 
> 
> Peter T. Parrish, Ph.D., President
> California Solar Engineering, Inc.
> 820 Cynthia Ave., Los Angeles, CA 90065
> CA Lic. 854779, NABCEP Cert. 031806-26
> peter.parrish at calsolareng.com  
> Ph 323-258-8883, Mobile 323-839-6108, Fax 323-258-8885