10:30am - 10:50am
The Role of Long Duration Energy Storage in Decarbonizing Power Systems
1Massachusetts Institute of Technology, United States of America; 2Harvard Kennedy School
Plans for a decarbonized power system call for a significant increase in generation from variable renewable energy (VRE) sources, i.e. wind and solar. Yet, the intermittency of these resources introduces new challenges in operating the grid, including the need for flexible generation to manage variations in VRE output and load, while minimizing emissions and cost impacts. Long duration energy storage (LDES) has been suggested as an enabling technology for realizing high VRE penetrations in future grids, because of its potential to flexibly time-shift VRE generation to match load. However, the current literature lacks assessment of the LDES technology requirements needed for decarbonizing the power system under various policy environments. This work seeks to fill that gap.
Using a high-temporal resolution electricity resource capacity expansion model, GenX, we evaluate the impact of the technology design parameters defining LDES technologies on their adoption in a future low-carbon power system dominated by VRE generation. The analysis is carried out for a region representative of a southern (e.g. Texas) power system in the United States through varied VRE and load profiles. The LDES technology design space is defined using power costs, energy costs, and charging and discharging efficiencies, based on the range of values reported in the literature for potential LDES technologies like power-to-gas to power, flow batteries, and thermal energy storage. By analyzing scenarios with differing climate policies, including region-wide carbon taxes, renewable energy requirements to target wind and solar generation, clean energy standards to target non-emitting technologies, and research and development efforts to target LDES technologies, I show the effect policy has on decarbonizing the electricity system and the technological characteristics of LDES that are more pertinent in each policy environment. My results focus on analyzing the effect of policies on the preferred design space for different LDES technologies and their deployment. Preliminary results indicate that there are identifiable regions in the LDES design space where LDES first beats out existing shorter duration lithium-ion batteries, and as costs drop and efficiencies increase, starts to also replace firm generation resources.
10:50am - 11:10am
Power System Planning at High Wind and Solar Penetrations Under Climate Change in Texas
1University of Michigan, Ann Arbor, MI, United States of America; 2Carnegie Mellon University, Pittsburgh, PA, United States of America; 3National Renewable Energy Laboratory, Golden, CO, United States of America; 4University of Colorado Boulder, Boulder, CO, United States of America; 5University of Washington, Seattle, WA, United States of America; 6encoord LLC, Denver, CO, United States of America
Climate change will likely affect various components of the electric power sector, including electricity demand, available thermal power plant capacity, and wind and solar generation. Using synchronous hourly data, we quantify the combined effect of these four impacts on four key planning metrics for the Texas power system: peak demand and net demand, wind and solar capacity values, and maximum hourly system ramps. We quantify climate change impacts for five climate change projections from 2041–2050 assuming Representative Concentration Pathway 8.5 relative to a reference period from 1996–2005. We find robust agreement across all five climate change projections that climate change will increase peak demand by up to 2 GW (4% of peak demand in reference period) and peak net demand by up to 3 GW (6% of peak net demand in reference period), suggesting increased investment need in generating or non-generating capacity regardless of wind and solar generation. We also find robust agreement across projections that climate change will reduce available thermal capacity during peak demand and peak net demand hours by up to 2 GW and increase maximum hourly ramps in net demand by up to 2 GW.
11:10am - 11:30am
Comparative Life Cycle Analysis for Value Recovery of Precious Metals and Rare Earth Elements from Electronic Waste
1School of Mechanical Engineering, Purdue University, West Lafayette, IN 47907, USA; 2Ecological Science and Engineering Interdisciplinary Graduate Program, Purdue University, West Lafayette, IN 47907, USA; 3Biological and Chemical Processing Department, Idaho National Laboratory, Idaho Falls, ID 83402, USA; 4Lyles School of Civil Engineering, Purdue University, West Lafayette, IN 47907, USA; 5Department of Systems & Industrial Engineering, University of Arizona, Tucson, AZ 85721, USA; 6Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; 7Division of Environmental and Ecological Engineering, Purdue University, West Lafayette, IN 47907, USA
There is an ever-increasing concern regarding electronic waste (e-waste), which is the fastest growing waste stream in the world along with economic growth. As e-waste contains highly toxic materials such as halogenated flame retardants and heavy metals, its proper management and disposition is paramount. Incentivized by various legislations and the intrinsic value of critical metals inside, recycling of e-waste is becoming an attractive business opportunity that also benefits the environment. A novel electrochemical recovery (ER) process has been developed as a promising alternative to the existing pyrometallurgical and hydrometallurgical processes based technologies to recover base metals, precious metals, and rare earth elements (REEs) from e-waste. Experimental results indicate that the ER process has lower chemical consumption, enhanced control, and reduced energy demand compared to the pyrometallurgical and the hydrometallurgical processes. To quantify and compare the environmental performances of the three technologies, this study conducted the life cycle analysis on each process. In this study, SimaPro 8.3 was used for the inventory analysis with the database like Ecoinvent 3.0 and US- US-EI U. EPA TRACI (USA 2008) and ILCD were used to assess environmental impacts.
Firstly, the environmental impact of different chemical components in each process was evaluated. The highest impactful input for the ER method is hydrochloric acid, and for the pyrometallurgical method is copper scrap, while for the hydrometallurgical method, it is hydrogen peroxide, an oxidizer that accelerates base metal extraction process, that dominates the overall environmental footprint. Other than the individual evaluation, several scenarios were developed for the comparative study of three processes. The revenue of e-waste processing is mainly from precious metals, REEs and the base metals. As the three processes have different recovery efficiency, the amount of outputs is different. In the first scenario, $1000 revenue was used as the functional unit. Results show that the ER process outperforms the other two processes in almost all impact categories adopted in TRACI and ILCD while there is no clear winner between the hydrometallurgical and the pyrometallurgical processes. Considering the gold is major revenue, which takes around 70%-90% of e-waste recovery, two scenarios were studied based on the functional unit of 1 kilogram of gold. REEs are co-product in the e-waste recovery. Among these scenarios, the first one used price allocation and results indicate ER process has lower than 20% impacts of the other two processes for most of the categories. Similar to the scenario with $1000 functional unit, there is no winner between the hydrometallurgical and the pyrometallurgical processes. As the REE recovery part for these three e-waste processes uses similar material inputs, the next case study separated the process of precious metals and the REEs recovery. Results still show ER has the lowest environmental impacts for all categories in recovering 1 kilogram of gold.
Overall, this study provides a comparative LCA on recovering precious metals from e-waste with the hydrometallurgical, the pyrometallurgical and the ER processes. The environmental viability of the ER process warrants the further development of the ER process at industrial scale.
11:30am - 11:50am
Semiconductors to Smart Devices: Capturing the System-Wide Impacts of a Growing Information & Communication Technology Infrastructure
1Lawrence Berkeley National Laboratory, United States of America; 2National Renewable Energy Laboratory, United States of America; 3Department of Energy, United States of America; 4Oak Ridge National Laboratory, United States of America; 5Argonne National Laboratory, United States of America
Data is being collected, transported, stored, and processed into actionable knowledge across all aspects of society and at unprecedented rates. This growth in data utility is enabled by a rapidly expanding information and communication technology (ICT) infrastructure. Cisco predicts nearly 20 billion internet-connected devices in the world by the year 2020. The reliance of ICT infrastructure across the economy is also transforming the industrial sector, with Apple, Amazon, Google, Microsoft, and Facebook currently the five largest global companies by market capitalization. This new connected economy has the potential to increase environmental sustainability through efficiency, substitution, and transformational impacts. However, similar to other high-impact general purpose technologies, such as electricity, ICT infrastructure assessment requires a systems-wide approach to account from the “invisible” energy and resource demands of ICT that occur remotely and out of sight of the end-user.
In this presentation we present some of the challenges and opportunities identified for assessing the impacts of an emerging connected economy. First, we characterize ICT infrastructure as comprised of three fundamental components: data centers, data networks, and the connected end-use devices embedded in consumer, industrial, and commercial products. We present how these components interact and may evolve, and discuss methods to estimate future equipment growth and accompanying operational energy requirements. Preliminary energy demand projections are presented to highlight the sensitivity among different assumptions and propose new metrics for capturing the impacts and efficiency of ICT infrastructure. Second, we discuss strategies to capture the upstream impacts of ICT infrastructure by identifying energy intensive manufacturing processes along with critical or regionally constrained material requirements across global supply chains. Strategies include utilizing aspects of traditional process life-cycle assessment methods with global economic data. Third, we propose a framework to assess the cost, energy, and performance benefits achievable through ICT-enabled “smart” applications in manufacturing, transportation, and building operation.
This presentation aims to highlight the challenges in understanding the implications of this growing portion of the economy and engage the audience to discuss new methods for evaluating system-wide impacts of emerging information technology products and services. Results from the session will be incorporated into strategic analysis efforts currently underway at the U.S. Department of Energy and shared with researchers via federal reports and academic publications.