Sanyo panel & CControllers [RE-wrenches]

[Christopher Freitas --- OutBack Power]

Tump - I agree that reliability is the most important part of any 
product - but its something that we can (and do already) know how to 
achieve for a product like this...

What I was talking about the engineering challenge of developing a high 
voltage input MPPT product - that the converter's efficiency has to be 
high enough to justify its cost - if the MPPT is only 95% efficient than 
it might not "capture" much additional power for most of the year from 
the PV array. Also, If the system has a 3000 watt PV array and it cost 
$5/watt to install - then each single percent of the MPPT's conversion 
efficiency is worth $150... 

The greater the difference between the PV array and the battery voltage 
- the lower the efficiency of the DC-DC converter.  Sure - there are 
tricks that can be done to reduce these losses - but they tend to make 
the product much more expensive - again reducing the overall "value" in 
the end.  

The bottom line is everything has trade-offs.  Higher voltage MPPTs will 
cost more, will be less efficient, and will be lower power than the 
current MX60 & FM80.  They can reduce the system installation cost by 
requiring fewer strings, smaller wire, smaller conduits - but only time 
will tell what wins out in the end...

There also is the option of doing AC coupled systems with grid-tie 
inverters - which allows for up to 600 VDC PV arrays right now - but a 
3000 watt grid-tie inverter is over $2000 - which would pay for a fair 
amount of additional wire and labor... and most of the grid-tie 
inverters are only 95% or so efficient... 


Christopher

Christopher Freitas
OutBack Power Systems, Inc.
cfreitas @ outbackpower.com  
www.outbackpower.com
Arlington WA USA
Tel 360 435 6030  


- - - -
Hosted by Home Power magazine

To send a message: RE-wrenches at topica.com

Archive of previous messages: http://lists.topica.com/lists/RE-wrenches/read

List rules & how to change your email address: www.mrsharkey.com/wrenches/etiquette.php

Check out participant bios: www.mrsharkey.com/wrenches/

Moderator: michael.welch at homepower.com
--^----------------------------------------------------------------
This email was sent to: michael.welch at re-wrenches.org

EASY UNSUBSCRIBE click here: http://topica.com/u/?bz8Qcs.bz9JC9.bWljaGFl
Or send an email to: RE-wrenches-unsubscribe at topica.com

For Topica's complete suite of email marketing solutions visit:
http://www.topica.com/?p=TEXFOOTER
--^----------------------------------------------------------------