Predictive models of capacity and power fade must consider a multiplicity of degradation modes experienced by Li-ion batteries in the automotive environment. Lacking accurate models and tests, lifetime uncertainty must presently be absorbed by overdesign and excess warranty costs. To reduce these costs and extend life, degradation models are under development that predict lifetime more accurately and with less test data. The lifetime models provide engineering feedback for cell, pack and system designs and are being incorporated into real-time control strategies.

The capital intensive nature of clean energy technologies suggests that manufacturing clean energy equipment has the potential to support state and local economic development efforts. However, manufacturing siting decisions tend to be complex and multi-variable decision processes that require in-depth knowledge of specific markets, the logistical requirements of a given technology, and insight into global clean tech trends. This presentation highlights the potential of manufacturing in supporting economic development opportunities while also providing examples of the financial considerations affecting manufacturing facility siting decisions for wind turbine blades and solar PV. The presentation also includes discussion of other more qualitative drivers of facility siting decisions as gleaned from NREL industry interviews and discusses strategies state and local policymakers may employee to bolster their chances of successfully attracting clean energy manufacturers to their localities.

This presentation for the January Stakeholder Engagement and Outreach webinar outlines the expanded need for workers in the wind industry and provides an overview of the DOE Wind Competition (to be held in May 2014) and the guiding principles of the competition.

The inclusion of interlinked temporal and spatial elements within integrated sensor data enables a tremendous degree of flexibility when analyzing multi-component datasets. The presentation illustrates how to warehouse, process, and analyze high-resolution integrated sensor datasets to support complex system analysis at the entity and system levels. The example cases presented utilizes in-vehicle sensor system data to assess vehicle performance, while integrating a map matching algorithm to link vehicle data to roads to demonstrate the enhanced analysis possible via interlinking data elements. Furthermore, in addition to the flexibility provided, the examples presented illustrate concepts of maintaining proprietary operational information (Fleet DNA) and privacy of study participants (Transportation Secure Data Center) while producing widely distributed data products. Should real-time operational data be logged at high resolution across multiple infrastructure types, map matched to their associated infrastructure, and distributed employing a similar approach; dependencies between urban environment infrastructures components could be better understood. This understanding is especially crucial for the cities of the future where transportation will rely more on grid infrastructure to support its energy demands.

The U.S. Department of Energy is conducting an assessment of vulnerabilities of the U.S. energy sector to climate change and extreme weather. Emphasizing peer reviewed research, it seeks to quantify vulnerabilities and identify specific knowledge or technology gaps. It draws upon a July 2012 workshop, ?Climate Change and Extreme Weather Vulnerability Assessment of the US Energy Sector?, hosted by the Atlantic Council and sponsored by DOE to solicit industry input.

Keynote presentation given at the 2013 NTEA Green Truck Summit titled Partnering with Industry to Shape the Future.

This presentation explains how liquid desiccant based coupled with an indirect evaporative cooler can efficiently produce cool, dry air, and how a liquid desiccant membrane air conditioner can efficiently provide cooling and dehumidification without the carryover problems of previous generations of liquid desiccant systems. It provides an overview to a liquid desiccant DX air conditioner that can efficiently provide cooling and dehumidification to high latent loads without the need for reheat, explains how liquid desiccant cooling and dehumidification systems can outperform vapor compression based air conditioning systems in hot and humid climates, explains how liquid desiccant cooling and dehumidification systems work, and describes a refrigerant free liquid desiccant based cooling system.

Concentrating solar power (CSP) deployed with thermal energy storage (TES) provides a dispatchable source of renewable energy. The value of CSP with TES, as with other potential generation resources, needs to be established using traditional utility planning tools. Production cost models, which simulate the operation of grid, are often used to estimate the operational value of different generation mixes. CSP with TES has historically had limited analysis in commercial production simulations. This document describes the implementation of CSP with TES in a commercial production cost model. It also describes the simulation of grid operations with CSP in a test system consisting of two balancing areas located primarily in Colorado.

Temperature has a significant impact on life, performance, and safety of lithium-ion battery technology, which is expected to be the energy storage of choice for electric drive vehicles (xEVs). High temperatures degrade Li-ion cells faster while low temperatures reduce power and energy capabilities that could have cost, reliability, range, or drivability implications. Thermal management of battery packs in xEVs is essential to keep the cells in the desired temperature range and also reduce cell-to-cell temperature variations, both of which impact life and performance. The value that the battery thermal management system provides in reducing battery life and improving performance outweighs its additional cost and complexity. Tools that are essential for thermal management of batteries are infrared thermal imaging, isothermal calorimetry, thermal conductivity meter and computer-aided thermal analysis design software. This presentation provides details of these tools that NREL has used and we believe are needed to design right-sized battery thermal management systems.

This presentation describes the results of NREL technology assessments for two early market full cell applications, backup power and material handling equipment.

This presentation discusses the Building America Program. This presentation discusses the background and goals of the program. A few hot topic technologies are discussed. Outreach activities are discussed as well.

This presentation describes the current status of the DOE's Energy Storage R and D program, including modeling and design tools and the Computer-Aided Engineering for Automotive Batteries (CAEBAT) program.

Description and history of the IEC 61215 qualification test, what it accomplishes, and what it does not accomplish that would be useful to the community. The commercial success of PV is based on long term reliability of the PV modules. Today's modules are typically qualified/certified to: (1) IEC 61215 for Crystalline Silicon Modules; (2) IEC 61646 for Thin Film Modules; and (3) IEC 62108 for CPV Modules. These qualification tests do an excellent job of identifying design, materials and process flaws that could lead to premature field failures. This talk will provide a summary of how IEC 61215 was developed, how well it works and what its limitations are.

This presentation covers modeling metal fatigue as a key step in photovoltaic (PV) module lifetime predictions. Described are time-dependent and time-independent case studies.

Description of how to make PV modules so that they are less likely to turn into safety hazards. Making modules inherently safer with minimum additional cost is the preferred approach for PV. Safety starts with module design to ensure redundancy within the electrical circuitry to minimize open circuits and proper mounting instructions to prevent installation related ground faults. Module manufacturers must control the raw materials and processes to ensure that that every module is built like those qualified through the safety tests. This is the reason behind the QA task force effort to develop a 'Guideline for PV Module Manufacturing QA'. Periodic accelerated stress testing of production products is critical to validate the safety of the product. Combining safer PV modules with better systems designs is the ultimate goal. This should be especially true for PV arrays on buildings. Use of lower voltage dc circuits - AC modules, DC-DC converters. Use of arc detectors and interrupters to detect arcs and open the circuits to extinguish the arcs.

This presentation discusses U.S. DOE Learning Demonstration Project goals, fuel cell vehicle and H2 station deployment status, and technical highlights of vehicle and infrastructure analysis results and progress.

Engineering robust adhesion of the junction-box (j-box) is a hurdle typically encountered by photovoltaic (PV) module manufacturers during product development. Furthermore, there are historical incidences of adverse effects (e.g., fires) caused when the j-box/adhesive/module system has failed in the field. The addition of a weight to the j-box during the 'damp heat' IEC qualification test is proposed to verify the basic robustness of the j-box adhesion system. The details of the proposed test are described, in addition to the preliminary results conducted using representative materials and components.

Recently there has been an interest in the use of thermoplastic encapsulant materials in photovoltaic modules to replace chemically crosslinked materials, e.g., ethylene-vinyl acetate. The related motivations include the desire to: reduce lamination time or temperature; use less moisture-permeable materials; or use materials with better corrosion characteristics. However, the use of any thermoplastic material in a high-temperature environment raises safety and performance concerns, as the standardized tests currently do not expose the modules to temperatures in excess of 85C, yet modules may experience temperatures above 100C in operation. Here we constructed eight pairs of crystalline-silicon modules and eight pairs of glass/encapsulation/glass mock modules using different encapsulation materials of which only two were designed to chemically crosslink. One module set was exposed outdoors with insulation on the back side in Arizona in the summer, and an identical set was exposed in environmental chambers. High precision creep measurements and performance measurements indicate that despite many of these polymeric materials being in the melt state at some of the highest outdoor temperatures achievable, very little creep was seen because of their high viscosity, temperature heterogeneity across the modules, and in the case of the crystalline-silicon modules, the physical restraint of the backsheet. These …

This presentation outlines an analysis of alternate methods to obtain stabilized power performance of CdTe and CIGS PV modules.

Presentation for biennial merit review of Biofuels Atlas, a first-pass visualization tool that allows users to explore the potential of biomass-to-biofuels conversions at various locations and scales.

Because of the sensitivity of some photovoltaic devices to moisture-induced corrosion, they are packaged using impermeable front- and back-sheets with an edge seal to prevent moisture ingress. Evaluation of edge seal materials can be difficult because of the low permeation rates involved and/or non-Fickian behavior. Here, using a Ca film deposited on a glass substrate, we demonstrate the evaluation of edge seal materials in a manner that effectively duplicates their use in a photovoltaic application and compare the results with standard methods for measuring water vapor transport. We demonstrate how moisture permeation data from polymer films can be used to estimate moisture ingress rates and compare the results of these two methods. Encapsulant materials were also evaluated for comparison and to highlight the need for edge seals. Of the materials studied, dessicant-filled polyisobutene materials demonstrate by far the best potential to keep moisture out for a 20 to 30 year lifetime.

One would hope that PV modules are designed for survival in the outdoors. However, it appears that some module types are really designed to pass the qualification (IEC 61216/61646) and safety (IEC 61730 and UL 1703) tests. While this has resulted in an overall increase in module reliability and a reduction in infant mortality, it may not result in the most cost-effective solution for long-term reliability and minimum power degradation. This paper will provide several examples of module types and even solar cells designed to pass the tests that do not result in good cost-effective long-term solutions for outdoor performance. This presentation is meant to stimulate a discussion about how to remedy this situation and improve the overall PV industry.

Tests to make quantitative predictions about photovoltaic (PV) modules are needed. This presentation proposes the creation of international quality assurance standards for PV modules.

The ability to accurately predict power delivery over the course of time is of vital importance to the growth of the photovoltaic (PV) industry. Two key cost drivers are the efficiency with which sunlight is converted to power and secondly how this relationship develops over time. The accurate knowledge of power decline over time, also known as degradation rates, is essential and important to all stakeholders--utility companies, integrators, investors, and scientists alike. Different methods to determine degradation rates and discrete versus continuous data are presented, and some general best practice methods are outlined. In addition, historical degradation rates and some preliminary analysis with respect to climate are given.