Dissertation: Background (2 of 3) - Energy Storage Technologies

2.   Energy Storage Technologies

Among others Chen et al (2009), Ibrahim et al (2008), Hadjipaschalis et al (2009) have thoroughly explored the state of ES technologies in the present and near-future. Their analysis roughly divides ES technologies into two categories (see Table 1), those that are useful for power quality management (capable of making short-term, high power, low energy interventions) and those that are useful for energy management (capable of mediating variations in supply and demand). Though power quality management (a.k.a. “Ancillary”) ES technologies have a definite role to play in the future stability of the electricity grid (e.g. Shayeghi et al 2009 and Hartikainen et al 2007), their likely contributions seem difficult to quantify in an absolute manner. Therefore, this study seeks to quantify the potential effects energy management (a.k.a. “Bulk”) ES could have on GHG emissions in the near-term while discussing qualitatively the advantages and drawbacks of the use of ES for power quality management with regard to GHG emissions.

Table 1: This table categorizes the energy storage technologies reviewed by Chen et al (2009) into either Power Quality Management or Energy Managment energy storage based on their applications.

Power Quality Management ES	Energy Management ES
Capacitors	Pumped-Hydro*
Super-capacitors	Compressed-Air*
Superconducting Magnetic ES	Thermal ES
Flywheels	Batteries (NaS*, ZEBRA, Li-ion)
Batteries (Lead-Acid, NiCd )	Flow Batteries (VRB*, ZnBr, PSB)
	Fuel Cells
	Solar Fuel

*Chen et al (2009) refers to proven MW-scale, multi-hour systems operating

By focusing on the “near-term” (in this case approximately the next two decades) means that some consideration must be given to the fact that some technologies are not yet viable on a commercial (large-) scale (Chen et al 2009). In fact without even considering cost limitations, only pumped-hydro power, compressed-air, and certain types of batteries and flow-batteries have examples of successfully developed MW-scale systems capable of operating for multiple hours. The remainder of this section briefly overviews bulk and ancillary ES technologies as well as the one type of ES-related smart-grid technology (specifically plug-in EVs). For a broad compilation of the physical and performance attributes of ES technologies please see the table in Appendix B.

a.    Bulk Energy Storage

Various forms of bulk ES have been employed by electric utility companies since the beginning of the 20^th century (Chen et al 2009). Not surprisingly, there are a variety of different types of bulk ES technology at different stages of development in use across the world today. After reviewing numerous academic articles and observing internal industry presentations on the topic, it is apparent that it is technologically feasible to incorporate substantial amounts of bulk ES on developed electric utility grids within the next two decades. As this assumption predicates the usefulness of this study, a review of these technologies is in order. However, rather than attempting to describe all potential ES technologies that may be employed by electric utilities, this brief review prudently highlights the three types of bulk ES that are in the latter stages of technological development and already have examples of multi-MW scale plants in regular operation somewhere in the world. While the three types outlined below (pumped hydro, compressed-air ES, and sodium-sulphur batteries) do not create an all-inclusive list of the possible bulk ES technologies (e.g. certain types of flow batteries and flywheels could have also been included) that could be included in this study, it is believed that those reviewed below should sufficiently validate the incorporation of ES technologies on developed electricity grids over the next two decades.

This review will not focus on underdeveloped ES technologies (e.g. hydrogen-based fuel cell systems), because it is unlikely that they will be widely installed at a substantial capacity prior to the latter quarter of the next two decades. This decision should avoid basing the remainder of the study on speculation about research and development timelines that may or may not materialize. Similarly, this review will not cover mature technologies that are unlikely to be employed at a significant scale within the foreseeable future due to practical limitations (e.g. Pb-acid and NiCd battery systems). Finally, this review will not focus on so-called thermal ES technologies, which heat or cool a medium during times of low-demand in order reap the benefits of the temperature difference during high-demand times (e.g. systems that freeze water overnight to assist in cooling buildings during the day). Admittedly, the use of the technologies in this last category could result in many of the same benefits with regard to reduced GHG emissions as the bulk ES technologies that are being reviewed. However, such technologies do not tend to produce electricity at the end of their charge/discharge cycle. Thus, they will only be employed by end-users of the electric utility grid. Whereas, the technologies being reviewed are able to both consume and produce electricity. This allows them to be used either by end-users or utility companies.

Aside from perhaps small-scale Pb-acid battery systems, the use of pumped hydroelectric storage (or simply ‘pumped hydro’) is perhaps oldest and most well-developed bulk ES technology in use today. Chen et al (2009) site examples of pumped hydro being used by electric utilities as early as 1929 and note that more than 100 GW of pumped hydro capacity is installed across the world today. Ibrahim et al (2008) explain that one of the main advantages of pumped hydro is the technology’s availability. Described simply, when electricity demand is low, electric pumps draw water from a lower reservoir and pump it to an upper reservoir. Then, when electricity demand is high, water flows from the upper to the lower reservoir through hydroelectric turbines similar to conventional hydroelectric dams (Ibrahim et al 2008). The use of reversible pump/generator assemblies acting as both pump and turbine is also possible (Hadjipaschalis et al 2009). Typically, pumped hydro plants use two naturally occurring or artificially constructed bodies of water as the reservoirs; however, Hadjipaschalis et al (2009) suggest that abandoned mines can also provide a suitable venue for the lower reservoir.

Due to the physical nature of pumped hydro (i.e. storage capacity is linearly proportionate to the height difference between the reservoirs and the amount of water stored), Baker (2008) states that the opportunities for significant advances in pumped hydro technology are limited. Recent reviews show rough agreement regarding the overall cycle efficiency of pumped hydro, which is listed as 71-85%, 65-80%, and 70-85% (for Chen et al 2009, Ibrahim et al 2008, and Hadjipaschalis et al 2009 respectively). The primary sources of inefficiency are losses from evaporation at exposed water surfaces and electrical conversion loses (Hadjipaschalis et al 2009). Thus, pumped hydro is considered a mature technology and its cycle efficiency is unlikely to change over the next two decades. Furthermore, an industry expert states that in the US it typically takes 7-10 years to take a pumped-hydro plant from initial conception to full operation (Boston and Mansoor 2010). This means that if efforts to install pumped hydro begin in earnest within the next few years, a substantial amount of new installed-capacity could realistically be operational well before the end of the next two decades.

Stressing the need for more installed ES within the immediate future the same industry expert suggests that compressed-air ES (or CAES) plants can be operational within a 3 year time period in the US (Boston and Mansoor 2010). CAES is typically considered to be a developed technology; however, most studies (e.g. Baker 2008 and Cavallo 2007) acknowledge only two operational multi-MW plants in the world (i.e. a 290 MW plant in Huntorf, Germany, installed in 1949 and a 110 MW plant installed in the 1970s in Alabama in the USA). Since newer, larger CAES plants are currently in the planning stage in the US (e.g. First Energy Generation is planning to build a plant in Norton, Ohio, USA, that could potentially be capable of running at 2700 MW; see Leidich 2010), it is not unreasonable to consider the potential of CAES in this study.

Ibrahim et al (2008) explain that large-scale CAES utilizes underground caverns made out of solid rock to store air at high pressure. These caverns can be “created by excavating comparatively hard and impervious rock formations, salt caverns created by solution- or dry-mining of salt formations, and porous media reservoirs made by water-bearing aquifers or depleted gas or oil fields, e.g. sandstone and fissured lime” (Chen et al 2009). The air is cooled and compressed into the cavern during times of low-demand using electric compressors (Hadjipaschalis et al 2009). During times of high-demand, the air is released from the cavern, heated, and combined and combusted with natural gas to retrieve the stored energy and produce electricity (Ibrahim et al 2008). Ibrahim et al (2008) note that for every 1 kWh produced using CAES approximately 0.7-0.8 kWh energy was used to compress air during low-demand and 1.22 kWh of natural gas is combusted. By way of comparison, Jaramillo et al (2007) suggest that conventional natural gas power plants are 28-58% efficient; this means that in a non-CAES plant 1.72-3.57 kWh of natural gas would need to be combusted to produce 1 kWh of electricity.

Recent articles suggest that the overall cycle efficiency of CAES is approximately 70-80% and 70% (see Chen et al 2009 and Ibrahim et al 2009 respectively). This is comparable (or slightly lower than) the cycle efficiency of pumped hydro; however, Hadjipaschalis et al (2009) point out that the self-discharge rate of CAES systems are minimal meaning that energy can be stored for months or years without significant additional losses. On the other hand, Chen et al (2009) state that CAES can only be used in association with natural gas plants. Thus, committing to CAES as a long-term strategy relies on the availability of natural gas or synthetic substitutes and requires accounting for some additional considerations (see Cavallo 2007). However, with regard to meeting the need for ES over the next two decades, CAES is another appropriate candidate.

While pumped hydro and CAES store energy in mechanical form, sodium-sulphur (NaS) batteries store energy in chemical form. Unlike conventional batteries (e.g. NiCd batteries), which store chemical energy in a solid form, NaS batteries consist of molten sulphur (on the positive electrode) and molten sodium (on the negative electrode) divided by a ‘solid beta alumina electrolyte’ (Hadjipaschalis et al 2009). The electrolyte allows the sodium ions to pass through the electrolyte during the charging and discharging phases as electrons pass through an external circuit (Hadjipaschalis et al 2009).

Baker (2008) explains that NaS batteries have 100% coulombic efficiency meaning that all of the electricity stored in the battery can be recovered, yet there is some disagreement regarding the overall efficiency of the system. Hadjipaschalis et al (2009) suggest that the heat produced during the charging and discharging phases is sufficient to maintain the battery’s operating temperature of 300-350ºC. However, Chen et al (2009) suggest that an additional heat source is needed, which reduces the overall performance of the system. This discrepancy leads to a difference in overall cycle efficiency (i.e. 89-92% or 75-90% according to Hadjipaschalis et al 2009 or Chen et al 2009 respectively). In either case, it appears that NaS batteries have higher cycle efficiencies than most pumped hydro and CAES technologies. Additionally, NaS batteries are expected to have a cycle life of approximately 2,500 cycles and have been proven to maintain a constant, multi-MW discharge of approximately 8 hours. Thus, NaS batteries have also been considered a viable bulk ES option in this study.

b.   Ancillary Energy Storage

While bulk ES technologies provide the opportunity for peak shaving and load leveling, which may significantly improve the efficiency of traditional generation plants and allow intermittent renewable generation systems to meet consumer demand, there are other ES technologies that may be better suited to meet the ancillary service needs of the grid, notably frequency regulation as described in section II.1. Traditionally, fossil fuel power plants are used to meet regulation needs; however, new ancillary ES plants are able to respond to regulation much more precisely than fossil fuel power plants (Shelton 2010).

Similar to bulk ES development, ancillary ES technologies are at various stages of development and deployment. Many ancillary ES technologies (e.g. superconducting magnet ES and ultracapacitors) are underdeveloped and are not currently ready for mass deployment (Pickard et al 2009). Other ancillary ES technologies (e.g. some battery systems and high-speed flywheels) already have several multi-MW plants in operation across the world today (e.g. Shelton 2010 and Capp 2010). However, the amount in operation today by no means covers a majority (or even a large minority) of the need. Such technologies are considered developed but under-deployed (or otherwise in the ‘pilot’ stage of deployment). Thus, given the appropriate incentives, ancillary ES could be brought into wider deployment soon (Jackson 2010).

The remainder of this study has been predicated upon the assumption ancillary ES technologies such as batteries and high-speed flywheels, which meet and exceed that ancillary service standards established by US regulatory authorities (McIntosh 2010), could feasibly compensate for any loss in regulation services caused by a reduction in traditional generation capacity. Even though these effects are not explicitly included in the calculations, Østergaard (2006 & 2008) highlights the need for such considerations as intermittent renewable generation such as wind replaces traditional generation. Since the need to ensure grid-stability through ancillary services such as frequency regulation is vitally important to the viability of any ES-related intervention, the following section illustrates an alternative solution to meeting that need through the use of smart-grid technology and an aggregation of smaller-scale ancillary ES.

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Dissertation: Background (1 of 3) - The Electricity Grid

II.    Background

1.   The Electricity Grid

Due to the contemporary structure of electric grids, electricity must be generated at the time of use, which causes inefficiencies that exacerbate the associated impact on anthropogenic climate change. Even everyday conditions such as diurnal fluctuations in electricity demand are a source of avoidable emissions (Dell and Rand 2001). The inclusion of ES systems on a grid has the potential to decouple electricity supply from demand thereby reducing the impact of such inefficiencies (Chen et al 2009, Dell and Rand 2001).

Chen et al (2009) indicate diurnal and annual demand fluctuations not only cause generation inefficiencies but also require that generation capacity be over-built to meet peak demand that may only last a few hours each year. With sufficient ES capacity to meet such peak-demand the construction of additional primary generation capacity can be delayed or avoided (Dell and Rand 2001).

Dell and Rand (2001) suggest that peak-shaving and load-leveling with ES can reduce the need to maintain plants in spinning reserve (i.e. generating electricity at sub-nominal values in case the plant needs to be called into regular service with short notice due to an unplanned plant failure or an unexpected increase in demand) to avoid a short-term shutdown. When fossil fuel plants are operating in spinning reserve, the GHG emissions per kWh of generation is greater than emissions during optimal generation (Voorspools and D’haeseleer 2000). Furthermore; this effect is not insignificant. As one report from the PJM Interconnection (a regulatory authority in the USA) shows annually the average GHG emissions from so-called ‘Marginal Units’ are over 50% greater than the overall average emissions of all generators (PJM 2009). This leaves a significant amount of room for emissions reductions. By charging ES systems during low-demand and allowing ES systems to meet demand during peak conditions or to be held in reserve for unplanned plant outages, plants can be maintained at optimal generation levels by running at a constant or near-constant rate (load-leveling or peak-shaving respectively) (Chen et al 2009).

Spinning reserve is one of two types of ancillary services required to ensure that the electricity grid seamlessly meets consumer demand. The second type of ancillary service is commonly called regulation (or frequency regulation or regulation power). Kempton et al (2008) explain that regulation maintains the grid at its optimal frequency (i.e. 60 Hz in the USA and 50 Hz in the rest of the world). When electricity generation exceeds demand the frequency increases. Contrapositively, the frequency decreases when electricity demand exceeds generation. In order to maintain the grid at the optimal frequency, ancillary service providers are called upon to provide regulation up (i.e. increasing generation or decreasing demand) and regulation down (i.e. decreasing generation or increasing demand) services (Kempton et al 2008). Currently, traditional generation plants are tasked with responding to regulation demands; however, as Shelton (2010) illustrates traditional plants are typically not capable of responding quickly to regulation requirements. Additionally, traditional plants acting in regulation mode are subject to the same inefficiencies as described in the previous paragraph. Thus, regulation services provide another opportunity for emissions reductions.

In addition to the limitations of traditional energy production, ES appears likely to play an even greater role with regard to future development plans and attempts to mitigate climate change. Perhaps most significantly, as developed nations look to integrate so-called ‘emission-free’ renewable energy technologies with intermittent generation into their energy portfolio (e.g. NCSC 2009), the integration of ES systems on the utility grid may be not only desirable but necessary for the sake of practicality and the economic viability of a large-scale implementation of renewable generating capacity (e.g. Pickard et al 2009, Aguado et al 2009, Benitez et al 2008).

Finally, Bayod-Rújula (2009) and Verhaegh et al (2010) suggest that the future of the electricity grid in developed countries will likely involve increased distributed (non-centralized) generation and/or the wide-scale use of EVs and residential heat-pumps, which may vastly alter the nature of the contemporary diurnal supply and demand cycles. In the US in particular mass production of EVs seems imminent within the next several years (e.g. Woody and Krauss 2010). Thus, earlier studies that have not consider these developments will need to be reexamined or taken with caution.

a.    Generation Technologies

Voorspools et al (2000) have suggested that studies analyzing GHG emissions associated with ‘emission-free’ technologies need to take into account indirect emissions embedded in construction in addition to the direct emissions from the fuel cycle, which is traditionally the limit of the scope of energy generation analyses. Weisser (2007) explains that all energy systems in use today have some associated GHG emissions, irrespective of the generation technology used. Performing a full life cycle analysis (LCA) of various generation technologies allows for a more comprehensive understanding of the actual GHG emissions associated with the electricity being transmitted through the grid. A comprehensive LCA tabulates the cumulative emissions (i.e. those associated with the entire life cycle of the generator), which is the sum of direct (i.e. emissions created during the generation process) and indirect (i.e. emissions created ‘upstream’ of the generation process such as fuel processing and plant construction and emissions created ‘downstream’ of the generation process such as plant decommissioning and fuel disposal) emissions (Weisser 2007). Further, even if the same generation technology is used, the level of associated GHG emissions can vary greatly depending on the source of the fuel (Jaramillo et al 2007).

For the purposes of this study, the range of generation technologies was limited to those in regular usage in the PJM territory and those that are expected to be added within the next two decades. The combination of nuclear, coal, natural gas, oil, hydroelectric power currently accounts for more than 95% of the electricity generated in the PJM territory (see section III.2.). Meanwhile, solar and especially wind power show significant promise for future expansion (Boston and Mansoor 2010). As such, finding reliable LCA GHG emissions values for all of these generation technologies is crucial for assessing the impact of installing ES on the electricity grid.

b.   Consumption Patterns

Even from the earliest development of the electric utility grid in the USA starting in the 1890’s, generation plants have been constructed and operated with the expectation that demand will be met by altering supply in a real-time manner (Schainker 2010). This means that for any alterations to the utility grid to be successfully implemented the needs of society must still be met. Thus, for the most part as utility companies and regulators plan for future developments, traditional consumption patterns can be assumed.

In PJM territory, which is not uncommon for developed countries, consumption patterns tend to follow a number of general patterns. Diurnally, demand tends alternate between on-peak (when demand is high) and off-peak (when demand is relatively low) between the day and night respectively. On a weekly basis, demand tends to be higher during the work week (i.e. Monday through Friday) and lower during weekends and on holidays (PJM 2009). Furthermore, most grid systems tend to experience seasonal fluctuations in demand annually; however, these fluctuations are harder to generalize across different territories as they depend on variables such as the local climate, local industries, and the preferred choice of air conditioning technologies in the territory (e.g. Lund and Münster 2003). With these considerations in mind, this study accounts for diurnal and weekly consumption patterns but does not attempt to quantify seasonal differences.

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Climategate Anniversary

Well, dear readers, it has been one year since "Climategate" hit the internet and the news. For a brief update on this phenomenon,  I recommend reading an op. ed. article written by my former professor Mike Hulme, which explains some of the changes in climate science research and climate policy approaches due to Climategate.

Happy Thanksgiving,

Sean Diamond

Dissertation: Introduction

I.    Introduction

As developed countries seek to modernize their electric utility grids, whether for the sake of cost savings, the environment, energy security, grid stability, or some combination thereof, many utility companies have started to implement or consider the use of large-scale energy storage (ES) systems to meet present and future demand. Careful consideration of present and future grid scenarios and issues such as inefficiencies in traditional non-renewable energy generation (Dell and Rand 2001), the intermittency of renewable energy sources (Pickard et al 2009), the increased use of distributed generation technologies (Bayod-Rújula 2009), and the introduction of plug-in electric vehicles (EVs) (Verhaegh et al 2010) provide a number of opportunities to implement energy management ES systems that reduce the overall greenhouse gas (GHG) emissions of a grid thereby lessening the region’s impact on anthropogenic climate change.

Sims et al (2007) explain that energy use currently accounts for 70 percent of global GHG emissions and of this 40 percent is used to produce electricity. Furthermore, approximately two-thirds of electricity is generated through the combustion of fossil fuels (i.e. coal, lignites, natural gas, and oil), which creates direct GHG emissions (Sims et al 2007). As a result, comprehensive attempts to mitigate anthropogenic climate change will likely involve addressing electricity generation and use in some form or another.

While a number of energy simulation studies have examined some combination of traditional generation, intermittent generation, and ES systems, the majority of recent studies appear to have optimized their results for financial gain (e.g. Aguado et al 2009, Benitez et al 2008, and Crampes and Moreaux 2010); however, optimizing a system for financial gain will likely result in inefficiencies with regard to GHG emissions (Voorspools and D’haeseleer 2000). Thus, with the issue of global climate change in mind, there is a distinct need to consider situations optimized to reduce GHG emissions.

The objective of this study is to assess the potential near-term impact on greenhouse gas emissions of a large-scale implementation of energy storage systems on an electric utility grid in a region with a fully developed grid system. To this end, technical data has been collected and a scenario-based computer simulation has been developed to model the electricity generation and consumption as well as the GHG emissions associated with the inclusion various types and amounts of ES technologies on an electric utility grid. 

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Table of Contents - References

Dissertation: Title Page, Abstract, & References

DISSERTATION: THE GHG EMISSIONS IMPACT OF INCLUDING ENERGY STORAGE SYSTEMS ON THE ELECTRIC UTILITY GRID

 by

 Sean Diamond

Dissertation presented in part-fulfilment of the degree of Master of Science in Climate Change in accordance with the regulations of the University of East Anglia

School of Environmental Sciences

University of East Anglia

University Plain

Norwich

NR4 7TJ

Submitted: 5 AUG 2010

 

© 2010 M.Sc. Student: Sean Diamond

This copy of the dissertation (and all related posts) has been supplied on condition that anyone who consults it is understood to recognise that its copyright rests with the author and that no quotation from the dissertation proposal, nor any information derived therefrom, may be published without the author’s prior written consent. Moreover, it is supplied on the understanding that it represents an internal University document and that neither the University nor the author are responsible for the factual or interpretative correctness of the dissertation.

------------------------- 

Abstract

This dissertation offers a quantitative study of the potential impact of a large-scale introduction of bulk energy storage technologies on a simulated electric utility grid modeled around the characteristics of the PJM Interconnection grid in the USA. In addition this dissertation provides a qualitative review and critique of a similar introduction of ancillary energy storage technologies to contemporary electricity grids. This study finds that an introduction of both types of energy storage technologies will have an especially favorably impact on anthropogenic climate change if it is accompanied by a shift away from fossil fuel powered electricity generation.

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References

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Benitez, L.E., P.C. Benitez, and G.C. van Kooten, 2008: “The economics of wind power with energy storage”, Energy Economics, 30, 1973-1989.

Boston, T. and A. Mansoor, 2010: “Welcome and Introduction”, PJM-EPRI Energy Storage Summit, presented on 20 APR 2010, video and slides available at , video viewed on 7 JUN 2010.

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Chen, H., T.N. Cong, W. Yang, C. Tan, Y. Li, and Y. Ding, 2009: “Progress in electrical energy storage system: A critical review”, Progress in Natural Science, 19, 291-312.

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Jackson, A., 2010: “Regulatory Session (Part 4)”, PJM-EPRI Energy Storage Summit, presented on 20 APR 2010, video and slides available at , video viewed on 14 JUN 2010.

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Kempton, W., 2010: “Technical Panel (Part 5)”, PJM-EPRI Energy Storage Summit, presented on 20 APR 2010, video and slides available at , video viewed on 10 JUN 2010.

Kempton, W., V. Udo, K. Huber, K. Komara, S. Letendre, S. Baker, D. Brunner, and N. Pearre, 2008: “A Test of Vehicle-to-Grid (V2G) for Energy Storage and Frequency Regulation in the PJM System: Results from an Industry-University Research Partnership”, edited January 2009, available at , 1-32.

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Sims, R.E.H, R.N. Schock, A. Adegbululgbe, J. Fenhann, I. Konstantinaviciute, W. Moomaw, H.B. Nimir, B. Schlamadinger, J. Torres-Martinez, C. Turner, Y. Uchiyama, S.J.V. Vuori, N. Wamukonya, and X. Zhang, 2007: “Energy Supply”, Climate Change 2007: Mitigation. Contribution fo Working Group III to the Fourth Assessment Report of the International Panel on Climate Change [B. Metz, O.R. Davidson, P.R. Bosch, R. Dave, and L.A. Meyer (eds)], Cambridge University Press, Cambridge, UK and New York, NY, USA.

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Voorspools, K.R., E.A. Brouwers, and W.D. D’haeseleer, 2000: “Energy content and indirect greenhouse gas emissions embedded in ‘emission-free’ power plants: results for the Low Countries”, Applied Energy, 67, 307-330.

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Woody, T. and C. Krauss, 2010: “Cities Prepare for Life with the Electric Car”, New York Times, available online 15 FEB 2010.

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Table of Contents 

A personal update: Utility-Scale Energy Storage

Hello Readers,

Tonight I attended a lecture hosted by 4CP about energy storage on the utility grid. If you've been following my blog, you may note the serendipitous nature of such a lecture for me. If you haven't, suffice it to say that I just got my results back from my Master's dissertation on the GHG emissions impact of incorporating energy storage on the utility grid, and I got a 'distinction'... the British way of noting 'hono(u)rs'.

I was quite pleased with the results of my dissertation; however, after sitting through a lecture by an industry professional on my dissertation topic and not learning a single thing (and in fact mentally noting a few inconsistencies with my background research), I have satisfied myself that I actually did learn something about energy storage on the utility grid while writing my dissertation.

Of course, I am using this post as an introduction to my next several posts, wherein I will post my dissertation in sections (after sending a copy to those who helped me out with the dissertation). Thus, please check back over the next several weeks if you are interested in learning what I learned about how adding energy storage to the utility grid will impact GHG emissions and subsequently anthropogenic climate change.

Till then, stay green dear readers!

~Sean