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
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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 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. -------- Original Message -------- Subject: RE: [emix] Power storage strategies From: "Edward Cazalet" <ed@MegaWattSF.com> Date: Mon, April 26, 2010 12:04 pm To: "'David RR Webber (XML)'" <david@drrw.info>, "'Phil Davis'" <pddcoo@gmail.com> Cc: <emix@lists.oasis-open.org>, <Toby.Considine@gmail.com> Yes, storage can play a big role in providing ancillary services and supporting the integration of wind and solar. I am a big advocate of distributed storage in very large amounts (see my attached editorial on the subject which has led to pending legislation to promote storage in California). Also see my storage company's website (www.megawattsf.com) below on this subject. Both of you raise the issue of what is behind the meters including storage. After thinking about this problem for some time, I think it is too difficult to communicate what is physically behind the meters. We would need to know the state of charge of storage devices, the charge/discharge efficiencies and nonlinearities of each type of battery, battery temperature that can limit use, and the opportunity costs of storage use. In some case what is behind the meter changes such as when an electric vehicle is plugged in, a storage battery is added or removed for maintenance and so on. And sometimes the storage may be ice storage which is useful when there is an air conditioning load and less useful when there is not air conditioning load. And as David said, each storage device needs new XML. The other approach is Transactional Energy, wherein the priced offers and transactions over current and forward intervals using frequent, small transactions can fully convey all of the necessary transactional information on what is behind the meter including any storage with no specifics on the devices or their state and no special XML. And with forward priced offers that form a forward price curve, automated self-dispatch of storage is much easier to do. Vice President and Co-Founder MegaWatt Storage Farms, Inc. 101 First Street, Suite 552 From: David RR Webber (XML) [mailto:david@drrw.info] Sent: Monday, April 26, 2010 8:42 AM To: Phil Davis Cc: emix@lists.oasis-open.org; Toby.Considine@gmail.com Subject: RE: [emix] Power storage strategies Can we get one of those 400 people to write some XML for us?!?! If telephone switch industry is a guide here - this means we already have 3 sets of battery subsystem XML - GE, Hitachi and Samsung - with more to follow. And of course each new model has new XML... -------- Original Message -------- Subject: RE: [emix] Power storage strategies From: "Phil Davis" <pddcoo@gmail.com> Date: Mon, April 26, 2010 11:26 am To: "'David RR Webber (XML)'" <david@drrw.info>, <Toby.Considine@gmail.com> Cc: <emix@lists.oasis-open.org> Actually, GE announced such a system last week and is hiring 400 people in Atlanta to staff the new business. It's a substation level product. Also, I have spoken personally with people at Hitachi and Samsung who are testing a 1 MW battery. Such a battery from another vendor is in test operation behind PJM's main offices. So local here takes on a new meaning depending on whether it is truly behind the customer meter, or behind the distribution grid meters (substations and the like), or on a transmission system. Theoretically, batteries of this size could replace generators used for voltage or frequency support.
From: David RR Webber (XML) [mailto:david@drrw.info] Sent: Monday, April 26, 2010 10:58 AM To: Toby.Considine@gmail.com Cc: emix@lists.oasis-open.org Subject: [emix] Power storage strategies It occurs to me that local storage can potentially play a role here - depending on its efficiency of course. One can anticipate that future technology will offer higher % there - especially if market forces drive that equation. Therefore - a future system could offset power surges by drawing on locally stored resources that were captured during off-peak or excess capacity. In fact such a system may notify suppliers that they can "push" excess power to local storage at some pre-determined cost point - and of course also need to indicate that the storage facility is at a certain % level, or if empty - accept units at a higher cost rate. ________________________________________________________________________ This email has been scanned for SPAM content and Viruses by the MessageLabs Email Security System. ________________________________________________________________________ --------------------------------------------------------------------- To unsubscribe from this mail list, you must leave the OASIS TC that generates this mail. Follow this link to all your TCs in OASIS at: https://www.oasis-open.org/apps/org/workgroup/portal/my_workgroups.php
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