11,111 research outputs found
Microgrids & District Energy: Pathways To Sustainable Urban Development
A microgrid is an energy system specifically designed to meet some of the energy needs of a group of buildings, a campus, or an entire community. It can include local facilities that generate electricity, heating, and/or cooling; store energy; distribute the energy generated; and manage energy consumption intelligently and in real time. Microgrids enable economies of scale that facilitate local production of energy in ways that can advance cost reduction, sustainability, economic development, and resilience goals. As they often involve multiple stakeholders, and may encompass numerous distinct property boundaries, municipal involvement is often a key factor for successful implementation.
This report provides an introduction to microgrid concepts, identifies the benefits and most common road blocks to implementation, and discusses proactive steps municipalities can take to advance economically viable and environmentally superior microgrids. It also offers advocacy suggestions for municipal leaders and officials to pursue at the state and regional level. The contents are targeted to municipal government staff but anyone looking for introductory material on microgrids should find it useful
Distributed Generation and Resilience in Power Grids
We study the effects of the allocation of distributed generation on the
resilience of power grids. We find that an unconstrained allocation and growth
of the distributed generation can drive a power grid beyond its design
parameters. In order to overcome such a problem, we propose a topological
algorithm derived from the field of Complex Networks to allocate distributed
generation sources in an existing power grid.Comment: proceedings of Critis 2012 http://critis12.hig.no
Significance Driven Hybrid 8T-6T SRAM for Energy-Efficient Synaptic Storage in Artificial Neural Networks
Multilayered artificial neural networks (ANN) have found widespread utility
in classification and recognition applications. The scale and complexity of
such networks together with the inadequacies of general purpose computing
platforms have led to a significant interest in the development of efficient
hardware implementations. In this work, we focus on designing energy efficient
on-chip storage for the synaptic weights. In order to minimize the power
consumption of typical digital CMOS implementations of such large-scale
networks, the digital neurons could be operated reliably at scaled voltages by
reducing the clock frequency. On the contrary, the on-chip synaptic storage
designed using a conventional 6T SRAM is susceptible to bitcell failures at
reduced voltages. However, the intrinsic error resiliency of NNs to small
synaptic weight perturbations enables us to scale the operating voltage of the
6TSRAM. Our analysis on a widely used digit recognition dataset indicates that
the voltage can be scaled by 200mV from the nominal operating voltage (950mV)
for practically no loss (less than 0.5%) in accuracy (22nm predictive
technology). Scaling beyond that causes substantial performance degradation
owing to increased probability of failures in the MSBs of the synaptic weights.
We, therefore propose a significance driven hybrid 8T-6T SRAM, wherein the
sensitive MSBs are stored in 8T bitcells that are robust at scaled voltages due
to decoupled read and write paths. In an effort to further minimize the area
penalty, we present a synaptic-sensitivity driven hybrid memory architecture
consisting of multiple 8T-6T SRAM banks. Our circuit to system-level simulation
framework shows that the proposed synaptic-sensitivity driven architecture
provides a 30.91% reduction in the memory access power with a 10.41% area
overhead, for less than 1% loss in the classification accuracy.Comment: Accepted in Design, Automation and Test in Europe 2016 conference
(DATE-2016
Sandy Regional Assembly SIRR Analysis
The NYC Mayor's Special Initiative for Rebuilding and Resiliency (SIRR) is a comprehensive effort to formulate recommendations guiding the rebuilding of neighborhoods impacted by Superstorm Sandy, and increase the resiliency of New York City as a whole. The plan combines citywide proposals with neighborhood-specific interventions in various neighborhoods. The federal Hurricane Sandy Rebuilding Task Force administered by HUD is responsible for overseeing the rebuilding and allocation of funds for all post-Sandy projects funded by the federal government; the Task Force is also charged with preparing a Hurricane Sandy Rebuilding Strategy to present to President Obama by August 2nd. Recommendations in the SIRR Report include plans to allocate the $294 million in HUD funding already provided to New York City and must comply with the Hurricane Sandy Rebuilding Task Force guidelines. After the Mayor's SIRR Report was released in June 2013, the Sandy Regional Assembly met to assess whether community-defined priorities and recommendations had made it into the Mayor's recovery plans. The following assessment reviews the SIRR Report from the context of the Sandy Regional Assembly Recovery Agenda, including both areas where there is synergy with the goals and recommendations of the Agenda and areas where the SIRR failed to address critical community priorities
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