emix — archive

[Phil Davis <tobyconsidine@gmail.com>]

Agree 
that we should be generic.  The real data of significance is 
available rate of charge/discharge.  A traditional generator can go 
indefinitely, and traditional demand response (kinda sorta) maintains a steady 
state for a defined period of time.  Depending on type, storage can behave 
similarly, one exception being batteries.  As batteries charge or 
discharge, the rate at which they do so tends to change, as does the max voltage 
available.  Of course we (and dare I say others) make marvelous devices to 
mitigate the impact of this, but the truth is that batteries never deliver rated 
capability for the entire span of a charge/discharge cycle.
 
So the 
question is whether this should be part of the communications, or whether the 
grid model learns this via statistical inference from meter data over 
time.  If the latter, then nothing overt is needed in the comm 
record.  If the former, then I am at the limit of my ability to expound on 
this, having attended liberal arts institutions.
 
Phil




From: Toby Considine 
[mailto:tobyconsidine@gmail.com] On Behalf Of Toby 
Considine
Sent: Monday, April 26, 2010 12:44 PM
To: 'David 
RR Webber (XML)'; 'Edward Cazalet'
Cc: emix@lists.oasis-open.org; 
'Phil Davis'
Subject: RE: [emix] Power storage 
strategies




Push?

Will 
that work as well as the Push technologies that are perennially the next wave on 
the ‘net

The 
correct push is appropriate pricing.
The 
correct measure of battery efficiency vs afternoon scarcity is 
pricing.

tc







"If 
something is not worth doing, it`s not worth doing well" - Peter 
Drucker










  

  

    

      
Toby 
      Considine
TC9, Inc
      
OASIS 
      Technical Advisory Board
TC Chair: oBIX & 
      WS-Calendar
      
TC 
      Editor: EMIX, EnergyInterop


    

      
  
    

      
Email: 
      Toby.Considine@gmail.com
Phone: 
      (919)619-2104
      
http://www.tcnine.com/
blog: 
      www.NewDaedalus.com




From: David RR Webber 
(XML) [mailto:david@drrw.info]
Sent: Monday, April 26, 2010 12:36 
PM
To: Edward Cazalet
Cc: emix@lists.oasis-open.org; 
Toby.Considine@gmail.com; 'Phil Davis'
Subject: RE: [emix] Power 
storage strategies


Ed,



Never 
under estimate an engineers ability to add 
complexity!



What 
is wrong with the simple notion of % full and capacity total in MW and storage 
ratio?!?!  Completely agnostic to the storage device 
characteristics!!!



If I 
know the storage is 60% full and has a total capacity of 100 MW - and a default 
ratio of power to storage of 4:1 then I know I can push 40 x 4 = 160 MW at the 
device to fill it.  Plus if device is sending out updating in intervals - I 
might send it 100MW - then it says it is 85% full - so I adjust 
accordingly.



Once 
it is full it sends "Stop!" - simple!



If 
you want to get clever on your backend systems - you may track actual storage 
ratio achieved compared to default - or the device can adjust that 
itself.



Thanks, 
DW