Aug 5, 2014
V2G is a topic discussed widely in the past decade. The costs of the batteries indicated that the LCOE of the battery kWh is quite high by itself and therefore any proceeds from grid services should substantially exceed this. The authors did not provide any of this type of analysis and I strongly urge them that they do so for this proposal to be stronger. Otherwise, both the idea and the business proposition are workable.
Aug 13, 2014
We have changed the Proposal Costs to reflect the costs of the battery in comparison to grid services. It is important to note that the value of grid services do not pay off the cost of the battery on their own, but it savings from BOTH V2G revenues and fuel that makes this model cost effective. Furthermore, in the paper, we conducted a sensitivity analysis around the cost of the battery replacement to see if battery costs would affect the cost-effectiveness of the V2G capable bus. We found that even if the battery replacement costs were double than what we expected, this would only reduce the cost effectiveness by about 10-15%. In addition, recent prices of battery have decreased significantly below what we expected- 20% less! Source: http://www.mynissanleaf.com/viewtopic.php?f=4&t=17168%20(from
Sep 3, 2014
This is an interesting business model for potentially contributing to mitigating the high costs of EV batteries. However, some questions remain, including (1) most fleet vehicles typically operate during the day, when power requirements are highest; hence, it is questionable how much electricity can be stored in these vehicles' batteries. (2) where does the company take the capital from to subsidise the battery costs, at least initially; (3) how about battery life with respect to frequent charging/discharging; (4) it would be interesting to understand the assumptions underlying the cost/profitability estimates. V2G is not a new concept and has been promoted as a benefit of EVs for some time. The one big problem is how to handle the economics of such a situation. Plugging into the grid for supply is a noble concept but the payback from the power company will be quite low likely. Couple low electricity prices with excess wear on the battery through multiple recharge events and it isn't clear how the owner will actually recuperate costs. Plus, charging the grid also means less range on the vehicle. There are no technical hurdles to overcome with the proposal and it could be tenable if the finances were suitable. There may be different parts of the world, or legislation, that makes the payback possible. The concept of V2G is appealing and benefits are know, however it is unclear how this particular project would actually contribute to that cause. Supporting fleet EV purchases through V2G revenues is a novel idea. It seems well supported by data at least for the specific PJM grid.The actual V2G revenues are crucial for the economic model though, and an actual simulation of revenues based on the published prices and the expected availability of the vehicle would be useful rather than relying on average prices. The proposal is innovative and imaginative. Nonetheless, it is unclear in its basis and, consequently, not particularly persuasive/appealing. Indeed, the main proposal consists in using EV as "small scale power plants" when parked and plugged, through V2G functions. This should help in "improving grid efficiency" and "validating wind and solar energy" but no details are provided on this aspects. For instance: how and to what extent these V2G functions can improve grid efficiency through the reverse use of limited capacity EV batteries? How and to what extent these "small scale power plants" are compatible with electricity demand in time and space in the network? How and to what extent "validating wind and solar energy" is possible/compatible with the availability in time and space of these "small scale power plants"? Considering the well known structural problems of the EV world - which prevented so far their wide diffusion - to what extent this greater "grid efficiency" can be considered a solution for these problems?
Sep 4, 2014
Thank you for your response and your comments. I will do my best to answer these very good questions about this plan. 1) While many fleet vehicles are used during the day (e.g. public transportation), the fleet vehicles we are focusing on, school buses, are not highly utilized during the day. The school bus routes vary, but generally they are out only for about 5 hours a day, once during the early morning (7am to 9am) and early afternoon (3pm to 5pm). In addition, since we are not buying electricity at low prices, and selling electricity back to the market at high demand, and instead performing frequency regulation services for the grid, the timing of performing V2G services is not as significant. PJM frequency regulation prices are very volatile and generally do not peak during the day dependably. 2) We are looking for sources for capital investment to subsidize the battery costs. We have explored the option of grants from governments, as well as applying for loans. In these efforts, the Delaware Sustainable Energy Utility has discussed with us the possibility of supplying us a low-interest loan for the capital investment. However, we are looking for additional financial options for capital investment. 3) Frequency regulation services generally require a lot of relatively minimal charges and discharges (about 20% of capacity up and down). We estimated that the additional wear on the life of battery would reduce the lifetime of the battery from 13-15 years down to 9 years. The additional cost of the replacing the battery was included in our cost benefit analysis. However, V2G also works best at 50% state-of-charge. Since V2G would reduce the time that the battery is at extreme states of charge (e.g. 0% and 100%), some authors have theorized that V2G would actually increase the life of the battery (Lunz et al 2012) as there would be less chemical potential deterioration. 4) I highly recommend that you take a look at our paper to understand the assumptions that we made in the cost benefit analysis. In order to be reasonable, we generally assumed conservative estimates of all our inputs. In addition, to test how our assumptions, we conducted a sensitivity analysis around our assumptions, and found that throughout the range of believable estimates, there was no point at which the cost effectiveness of the electric bus became negative. So, whichever inputs you think are the proper one, a V2G capable electric school bus would still make sense. 5) I would like to stress that electricity prices do not determine the profits for the V2G bus. Instead, the frequency regulation price determines the profit, and is independent of electricity prices. In fact, low electricity prices would increase the cost effectiveness of the school bus since it would reduce the fuel cost. 6) This project will directly apply the concept of V2G to a pilot project. We will contribute to this cause by actually testing the business model that utilizes V2G to make electric fleet vehicles tenable to consumers. We hope that this pilot project, coupled with the University of Delaware’s pilot project, will validate V2G technology and make electric vehicles affordable, leading to large scale penetration of electric vehicles. 7) The simulation of revenues was based on published prices, as posted by PJM. The average over the last year was $28/MWh, as stated by our paper, but this is the actual price that we would get if participating on the frequency regulation market. These prices were not estimated, were based on published prices, and also include the availability of the bus (see above, about 19 hours a day). 8) While there could be questions that the “limited capacity” of the an electric vehicle could limit its participation on the grid, remember that a heavy duty fleet vehicle would have a large battery, and would be coupled with other vehicles to create a very large aggregate battery, not constrained by size in any way. In fact, this is already being done by the University of Delaware’s pilot project, which has shown that it is plausible for aggregate electric vehicles to perform frequency regulation. This will improve grid efficiency since batteries are incredibly efficient in regulating the frequency as compared to the current participants, such as oil plants. The profits gained from participating in this market easily outweighs the costs of the structural problems of the EVs. 9) For the short term, V2G-capable electric vehicles are best suited for the frequency regulation market. However, in the long term, large scale penetration of V2G would imply significant amounts of storage. Given that most cars are not utilized for 23 hours of the day (Pearre 2011), this provides an opportunity for cheap storage. Likewise, many papers (Budischak et al 2013, Heide et al 2011) that focus on large scale penetration of wind and solar, i.e. over 60% of electricity generation provided by renewable energy, suggest that three things are required: geographic and technological diversity of electricity sources, increased amount of transmission, and increased amount of storage. Increasing the penetration of V2G can provide substantial amounts of storage, and increase the reliability of a grid that is mostly renewable. Thank you for the really insightful questions and comments, I hope this answers them. I look forward to the continued discussion about this proposal! Sources: Our paper: http://www.sciencedirect.com/science/article/pii/S0306261914003420 PJM Historical Regulation Market Prices: http://www.pjm.com/markets-and-operations/market-settlements/preliminary-billing-reports/pjm-reg-data.aspx Budischak et al: http://www.ceoe.udel.edu/windpower/resources/BudischakEtAl-2013-CostMinimizedWindSolarPJM.pdf Heide et al: http://www.sciencedirect.com/science/article/pii/S0960148111000851
Sep 6, 2014
Integrating the Carbon Capture & Biological Sequestration approach with CO2 emission reduction would be more helpful especially when the CCBS approach includes, involves potential for providing nourishing food to population. Along with marine a land bases CCS program would be beneficial. A proposal outlining such an approach is available. Following is a link to such a proposal. https://www.climatecolab.org/web/guest/plans/-/plans/contestId/1300103/planId/1310401 This would help bolster the efforts directed at finding workable solution to climate change..
Osero Shadrack Tengeya
Sep 17, 2014
Hi eRev and your friends, kindly consider voting for my proposal shown on this link. https://www.climatecolab.org/web/guest/plans/-/plans/contestId/1300206/planId/1002 Thanks.
Sep 23, 2014
Hi erev, Please consider voting for my proposal, https://www.climatecolab.org/web/guest/plans/-/plans/contestId/1300801/planId/1309001 Good luck with your entry! Asante/Thank-you @conserveaction
Sep 27, 2014
Interesting work, although I do not see that the 2014 paper accounts for electrical efficiency losses. With energy moving through the batteries from both driving cycles and V2G , this must be a big part of the financial equation. My research shows electrical efficiency charging/discharging of only about 68%. Thank you.
Oct 4, 2014
Congratulations!!! Please check the "Discusion Section" in the "Community" label... Proposal of activity during the Conference Session of 2014 Winners... https://www.climatecolab.org/web/guest/discussion#discussion%3DpageType%3ATHREAD%2CthreadId%3A1337218