Factoring the Cycle Aging Cost of Batteries Participating in Electricity Markets

When participating in electricity markets, owners of battery energy storage systems must bid in such a way that their revenues will at least cover their true cost of operation. Since cycle aging of battery cells represents a substantial part of this operating cost, the cost of battery degradation must be factored in these bids. However, existing models of battery degradation either do not fit market clearing software or do not reflect the actual battery aging mechanism. In this paper we model battery cycle aging using a piecewise linear cost function, an approach that provides a close approximation of the cycle aging mechanism of electrochemical batteries and can be incorporated easily into existing market dispatch programs. By defining the marginal aging cost of each battery cycle, we can assess the actual operating profitability of batteries. A case study demonstrates the effectiveness of the proposed model in maximizing the operating profit of a battery energy storage system taking part in the ISO New England energy and reserve markets

Computer modeling of photodegradation

A computer program to simulate the photodegradation of materials exposed to terrestrial weathering environments is being developed. Input parameters would include the solar spectrum, the daily levels and variations of temperature and relative humidity, and materials such as EVA. A brief description of the program, its operating principles, and how it works was initially described. After that, the presentation focuses on the recent work of simulating aging in a normal, terrestrial day-night cycle. This is significant, as almost all accelerated aging schemes maintain a constant light illumination without a dark cycle, and this may be a critical factor not included in acceleration aging schemes. For outdoor aging, the computer model is indicating that the night dark cycle has a dramatic influence on the chemistry of photothermal degradation, and hints that a dark cycle may be needed in an accelerated aging scheme

Economic Aging and Demographic Change

This paper presents a generalized model of overlapping generations with economic aging of households. Economic age is defined as a set of personal attributes such as earnings potential and tastes that are characteristic of a person's position in the life-cycle. We separate the concepts of economic age and time since birth in assuming only a small number of different states of age. Agents sharing the same economic characteristics are aggregated analytically to a low number of age groups. The model thus allows for a very parsimonious approximation of life-cycle differences in earnings, wealth and consumption. As an illustration, we quantitatively apply the model to study the impact of demographic change.Overlapping Generations, Aging, Demographic Change, Life-cycle

Prediction Of Cancer Possibility By Pattern Recognition And Statistical Study Of Expression Of Gene Level Of Cancer Cells

The activity of the p53 tumor-suppressor protein has a key role in controlling both cancer and aging: under activity encourages the growth of cancer, and over activity can accelerate the aging process. The p53 protein is a tumor suppressor encoded by a gene whose disruption is associated with approximately 50 to 55 percent of human cancers. The p53 protein acts as a checkpoint in the cell cycle, either preventing or initiating programmed cell death (Apoptosis). p53 regulating genes MDM2, PARP, Oncogenicras, and p21 etc play a crucial role in tumor suppression

Stress-corrosion characteristics of aluminum casting alloy M-45

Evaluation of the stress-corrosion characteristics of aluminum alloy M-45 shows that the most favorable artificial aging cycle for this alloy, with regard to optimum strength and stress-corrosion resistance, appears to be 400 degrees F for 12 hours

Rejuvenation and Memory in model Spin Glasses in 3 and 4 dimensions

We numerically study aging for the Edwards-Anderson Model in 3 and 4 dimensions using different temperature-change protocols. In D=3, time scales a thousand times larger than in previous work are reached with the SUE machine. Deviations from cumulative aging are observed in the non monotonic time behavior of the coherence length. Memory and rejuvenation effects are found in a temperature-cycle protocol, revealed by vanishing effective waiting times. Similar effects are reported for the D=3$site-diluted ferromagnetic Ising model (without chaos). However, rejuvenation is reduced if off-equilibrium corrections to the fluctuation-dissipation theorem are considered. Memory and rejuvenation are quantitatively describable in terms of the growth regime of the spin-glass coherence length.Comment: Extended protocols. Accepted in Phys. Rev. B. 10 postscript figure

From Duty to Right: The Role of Public Education in the Transition to Aging Societies,

This paper argues that currently advanced, aging economies experienced a qualitative change in the role of public education during the process of industrialization. In the early phases of the Industrial Revolution, public education was regarded as a duty that regulated child labor and thereby discouraged childbirth. As these economies developed and the population aged, younger generations came to view public education as a right, whereas older generations desirous of other public services became more politically in.uential. The eventual policy bias in favor of the elderly placed a heavier education burden on the young, inducing them to have fewer children. This vicious cycle between population aging and the undersupply of public education may have decelerated the growth of advanced economies in the last few decades.

Chopper-controlled discharge life cycling studies on lead-acid batteries

State-of-the-art 6 volt lead-acid golf car batteries were tested. A daily charge/discharge cycling to failure points under various chopper controlled pulsed dc and continuous current load conditions was undertaken. The cycle life and failure modes were investigated for depth of discharge, average current chopper frequency, and chopper duty cycle. It is shown that battery life is primarily and inversely related to depth of discharge and discharge current. Failure mode is characterized by a gradual capacity loss with consistent evidence of cell element aging