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[Girish Ghatikar <ed@cazalet.com>]

One more "green" question -- How does we accommodate moving resources? http://news.yahoo.com/s/afp/20100219/ts_alt_afp/scienceelectricityenvironmentautomobiletechnology Does anyone know $30/hour currently paid by PJM interconnection is equivalent to in kW? Thanks, Rish Girish Ghatikar wrote: > Ed, > > These are some good use cases. I suggest few simple interaction > diagrams indicating the communication flow between the actors involved. > > Thanks, > Rish > > Ed Cazalet wrote: >> >> Made a minor correction in use case 4. >> >> David, >> >> You posed several use cases, but let me start with the use case you >> highlighted which was green energy provided by a retail service >> provider. >> >> The retail service provider provides you with green energy from one >> of several portfolios or from combinations of these portfolio. The >> green portfolios could be as follows: >> >> 1. Consider a set of local solar and wind resources on a micro grid >> connected to you and other customers. The retailer contracts with you >> to provide energy only from these sources at a dynamic price that >> depends on supply vs. demand or he provides you a formula allocation >> of actual generation at a price. Price, quantity and delivery >> interval and delivery location as well as a contract reference would >> give the customer, the retailer and the generators all the >> information they need given the contracts the retailer had signed. >> The retailer includes in his price to customers the price paid to the >> generator, the price of the distribution, cost of distribution >> losses, markup, and perhaps taxes. The retailer would have to have >> access to the generators' meter data in real time to inform the >> customers of actual energy delivery. Customers would automatically >> turn smart devices on and off depending or price or supply. Toby's >> green fountain would work with this. The delivery intervals for the >> transactions could be seconds or shorter. If this micro grid is not >> connected to the main grid and the only generators on the micro grid >> are wind and solar and are all contracted with the retailer a >> customers is assured he is getting only wind or solar energy. The >> retailer could also own batteries or contract for battery services to >> reshape the green deliveries accounting for the losses in storage and >> the cost of the battery storage in the price of green energy to the >> customer. Alternatively the customer could own or contract for >> battery storage to shape energy to his needs. No need for >> certificates here as the retailer has only wind and solar energy to >> serve you and he can only sell what he has on a closed microgrid. >> >> 2. Same as case one but the green generation is remotely located on >> the transmission grid. Assume the retailer has a direct contractual >> relationship the a set of green generators to take all of a wind or >> solar generator output. Then the only difference is that the retailer >> must pay for the transmission charges and losses. On an ISO >> controlled grid such as PJM or the California ISO. The retailer will >> be pay a grid access charge, a marginal congestion charge and incur >> marginal losses. Prices for these services are readily available in >> these ISOs. However the traceability of the electrons is lost. As >> long as the retailer has access to the meter data from the generators >> he can assure that he did not take out of the grid more wind and >> solar energy than this contracted generators put in. However, it >> could be that congestion on the grid would require that the green >> electrons be delivered somewhere else and a coal plant be dispatched >> to actually deliver electrons to the customers even though the >> customers are only getting energy when the wind and solar generators >> are producing. Again no green certificates are needed. >> >> 3. Same as 2 except the retailer is dealing with many green >> generators and customers. A third party or the ISO could host an >> exchange to take the wind and solar generator meter readings and >> allocate the generation among the retailers perhaps based on a >> sharing rule or a price based auction. Again no need for >> certificates. Intervals for this exchange could be as short as >> desired. Storage can still be used. The exchange operator might offer >> to sell excess wind and solar into the rest of the grid and buy an >> equal amount back at a later time using the grid like a storage >> battery. However he may be displacing hydro energy when he sells it >> and buying back coal energy which an obvious non green result but it >> provides greater reliability of service to customers. >> >> 4. Same as 3 except the a third party creates bank accounts of green >> kwh for each generator and each customer. A separate set of accounts >> is created for each delivery interval. A generator's account would be >> credited for each kwh generator in an interval. A customer's account >> would be debited for each kwh consumed in an interval. The retailer >> would buy kwh from the generator accounts and deposit them in the >> customer accounts. No kwh could be sold twice. The retailer could >> deliver energy from the main grid whenever he has a matching kwh in >> the customer account. >> >> 5 Same as 4 except there is one account per year for each customer >> and generator. There is no need for the retailer to buy energy >> directly from any wind or solar generator. Wind and solar generators >> continue to be credited with deposits in their an annual accounts. >> The retailer will contract with the green generators to buy only >> deposits in his account and the generators will sell their actual >> generation to anyone on the grid. Customers accounts will be debited >> a kwh of wind solar in their accounts and for each kwh used. To >> facilitate commerce each bank can create a */certificate/* for a kwh >> of green energy ( which is a form of currency) that can be freely >> traded. Since the generators are getting one stream of revenue for >> the energy to the grid and a second stream of revenue for the >> certificates, the price of the certificates will not include the >> price of the energy. With annual kwh certificates there will be more >> market liquidity than if certificates were set up on very short >> intervals. However with annual accounts we are essentially using the >> grid as a storage battery and there can be environmental consequences >> as described above. >> >> Case 5 is essentially how environmental registry services support >> green energy today with registered environmental certificates that >> can be moved among many parties and registries. In this later case >> emix can describe the energy and the certificates as price, quantity, >> delivery interval and location records with a reference to the >> contract, market or certificate authority. >> >> Probably some diagrams and editing would improve these uses cases if >> they are helpful. >> >> Ed >> >> Edward G. Cazalet, Ph.D. >> >> 101 First Street, Suite 552 >> >> Los Altos, CA 94022 >> >> 650-949-5274 >> >> cell: 408-621-2772 >> >> ed@cazalet.com