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Subject: RE: [emix] Ramp intervals
The ramp rate curve is a characteristic of the unit that determines whether it will be selected and what the five minute dispatches will look like once the unit is online (e.g when ramping from 100 MW to 200 MW). It is not strictly part of the three part bid which is purely economic; $/MW, Startup cost and Minimum load cost. While the nominal ramp rate curve is determined by physical unit characteristics it is possible to submit reduced ramp rate curves that are lower than the units capablity to reduce wear and tear or other "economic" reasons. ________________________________________ From: Toby Considine [tobyconsidine@gmail.com] on behalf of Toby Considine [Toby.Considine@gmail.com] Sent: Wednesday, September 15, 2010 2:25 AM To: 'Edward G. Cazalet'; emix@lists.oasis-open.org Subject: RE: [emix] Ramp intervals So, if I understand this, ISO markets just set delta T small enough in the ramp periods that they do not care. The other proposal would be that in EMIX, we defined a generic enumeration object which has two variations: Simple (a number) or ramp (begin rate, end rate) Another indication might be a “variance allowed”, such that if your [ramp] variation is greater than this, you must divide the intervals. tc ________________________________ "If something is not worth doing, it`s not worth doing well" - Peter Drucker ________________________________ Toby Considine TC9, Inc TC Chair: oBIX & WS-Calendar TC Editor: EMIX, EnergyInterop U.S. National Inst. of Standards and Tech. Smart Grid Architecture Committee Email: Toby.Considine@gmail.com<mailto:Toby.Considine@fac.unc.edu> Phone: (919)619-2104 http://www.tcnine.com/ blog: www.NewDaedalus.com From: Edward G. Cazalet [mailto:ed@cazalet.com] Sent: Tuesday, September 14, 2010 6:01 PM To: Toby.Considine@gmail.com; emix@lists.oasis-open.org Subject: RE: [emix] Ramp intervals I know there is another thread from this email related to DR “ramps”, but this note is focused on generation although much of it applies to DR and loads as well. I disagree that each EMIX product needs a ramp component. Some EMIX product may have a ramp component. A good example is bidding into ISO markets. The ISO accepts multi-part bids from generators and dispatches them, Part of the bid is a ramp rate curve vs. MW output (not a WS-calendar construct ). The output of the ISO process is hourly and five minute schedules for the generator, without any explicit WS-Calendar-like ramp. Yes the generator does not move instantly from the level in one interval to the next in a step, but the balancing processes of the ISO accommodate this. Most forward wholesale contracts may be scheduled hourly. Ramping up and down from levels in one hour to next often has an assumed ramp ( from 10 minutes before the hour to 10 minutes after the hour). As Phil has said, a registration process can deal with any standard ramp assumptions. For financial contracts the ramp can be ignored. In automated markets it is easier to deal with schedules where the ramp is a characterized by series of shorter interval schedules. It is also how we meter delivery as energy over an interval. This provides standard products and contracts in each interval. If every offer has a different ramp rate on each end markets it is harder to get liquid markets. Also, think of the complexity in adding up a large portfolio of schedules each with a different embedded WS_Calendar ramp rate. The final schedule with include all of the ramps, all with different durations and start times. It is much easier to do what we do today which is a sequence of yearly, monthly, daily, hourly, 5 min schedules each of which are simple block schedules, transactions, or offers. Edward G. Cazalet, Ph.D. 101 First Street, Suite 552 Los Altos, CA 94022 650-949-5274 cell: 408-621-2772 ed@cazalet.com<mailto:ed@cazalet.com> www.cazalet.com<http://www.cazalet.com> From: Toby Considine [mailto:tobyconsidine@gmail.com] On Behalf Of Toby Considine Sent: Tuesday, September 14, 2010 12:20 PM To: emix@lists.oasis-open.org Subject: [emix] Ramp intervals Do we need a construction within EMIX for ramping intervals? I am tieing this to such things as the 3-part generation bids Consider the case of a long generation cycle followed by a discrete ramp cycle. The whole shape is the electricity produced. Things don’t just shut down, there is some electricity that needs to go somewhere, and if it goes onto the grid, it must be planned for and balanced. The large rectangle on the left is the scheduled generation period. The it may be scheduled for three hours, it may be scheduled for 1, it may be scheduled for 16. The slopey bit on the right just comes along for the ride. [cid:image001.png@01CB548D.BA8FA890] The shape above is an ugly interval.We could solve it by making an infinite number of intervals, or at least enough so that we can assume that each one was flat. I think it would be an error to recreate intro calculus within EMIX… [cid:image002.png@01CB548D.BA8FA890] WS-Calendar supports separating a scenario like that above, in which the things are split into two linked intervals. It is easy to schedule the interval on the left, to any length, It is the supply of a constant amount of energy for a variable period of time, as per contract. The funny looking shape on the right, comes along for the ride; buying the left is buying the right. This occurs in many scnarios in homes / buildings / energy / … So in Emix, we have a product, and then we have a ramp. The ramp is a predictable varying, but constant duration (probably) delivery of product. There may be ramp ups and ramp downs. We need to include handling of ramped energy in each EMX product. ________________________________ “It is difficult to get a man to understand something, when his salary depends upon his not understanding it” -- Upton Sinclair. ________________________________ Toby Considine TC9, Inc OASIS Technical Advisory Board TC Chair: oBIX & WS-Calendar TC Editor: EMIX, EnergyInterop U.S. National Inst. of Standards and Tech. Smart Grid Architecture Committee Email: Toby.Considine@gmail.com<mailto:Toby.Considine@fac.unc.edu> Phone: (919)619-2104 http://www.tcnine.com/ blog: www.NewDaedalus.com<http://www.NewDaedalus.com> ********************************************************************************************* The foregoing electronic message, together with any attachments thereto, is confidential and may be legally privileged against disclosure other than to the intended recipient. It is intended solely for the addressee(s) and access to the message by anyone else is unauthorized. If you are not the intended recipient of this electronic message, you are hereby notified that any dissemination, distribution, or any action taken or omitted to be taken in reliance on it is strictly prohibited and may be unlawful. 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