Some steps for India to move towards 100% Renewable Energy
India is highly dependent on coal for producing its electricity. Even though the per-capita emissions of GHG in India is lower than that of most developed, its total emissions of GHG is close to some of the big polluters. No wonder there is an increasing pressure on India to move towards Renewable Energy (RE). India now produces solar and wind-based electricity at costs lower or comparable to that of coal-based electricity. However, while coal-based electricity generation can be increased or decreased at will to match demand, that is not the case for solar and wind-based electricity, as the quantity produced entirely depends on nature, the sun-hours and the wind-hours. Only way generation could match demand is if there are massive energy-storage systems. This paper examines how office and commercial complexes in India can take the lead in becoming a 100% RE user by installing energy storage systems and carrying out effective energy management. It would show that this can be done to reduce the cost of electricity for such complexes, while they become near-100% RE users. The industrial-complexes and housing complexes may use a similar strategy to become an RE-user and this would help move India substantially towards 100% RE. The paper examines the technology and economic challenges that have to be overcome to get there.
Some studies on impact of temperature and DoD on performance of lithium-ion battery pack
It is known that the life of a Lithium-ion (Li-ion) battery is affected by charge/discharge rates, temperature, and depth of discharge (DoD). This paper investigates the effect of temperature and DoD on a 18650 Li-Ion cell. An experiment is set up to analyze the impact of temperature and DoD on the performance of Li-Ion cells. The test temperatures of 25°C and 35°C, whereas DoD of 80% and 90%, are considered for the analysis. The paper aims at studying the effects of these parameters on capacity degradation, discharge energy efficiency, and coulombic efficiency over the cell's lifetime.
Sustainable Photovoltaics
This chapter covers the largest set of projects in SERIIUS that can be viewed overall as having three distinct themes. First is the development of new low-capital thin-film photovoltaic (PV) technologies by high-throughput manufacturing processes with a focus on solution-based roll-to-roll processing. This effort was highly integrated with the development of thin glass substrates and packaging from Corning, and focused on absorbers made from CuInGaSe2, CuZnSnSeS, organic molecules such as fluorinated polymers, perovskite solar cells based on methyl ammonium lead iodide (MAPbI), and silicon. Significant progress, including world-record devices, was achieved in a number of areas, and substantial improvements in lifetime were attained. Second is an assessment of the stability and failure mechanisms of PV in hot/dry and hot/wet climates. This work included assessing PV module stability across the seven climate zones of India and in the United States. The importance of dust and particulates was assessed. New failure mechanisms were identified, in particular to the hot/dry and hot/wet climates, and an international working group was convened. Coupled to developing new PV technology and understanding degradation pathways, an effort was made in multiscale modeling – from atoms to modules – to begin to connect the basic science to the ultimate deployability of the PV devices and modules. Here, the potential importance of bifacial modules was assessed.
Understanding the Li-ion battery pack degradation in the field using field-test and lab-test data
Li-Ion cell manufacturers do provide some information in relation to their cell performance at different but constant charge/discharge rates and at different and constant temperatures, but hardly any of these can be extended to field conditions, where charge/discharge rates and temperature are continuously varying. This paper attempts to take the primary cell testing data gathered in a lab environment and create a first-order model for battery behavior in real-life conditions. At the same time, real-life data for battery packs in 3-wheeler vehicles are obtained on a continuous basis, when driven or when the battery is being charged. The battery packs used are of 1.25 kWh without any forced cooling, and the vehicles are driven in the city of Chennai in India, where in 24 h, the average temperature varies from 25 °C to 48 °C in summers and from 18 °C to 32 °C during winters. The State of Health estimate obtained from the model (and the lab data for cells) is then compared with actual field data; further variances between the two and possible reasons for such variance are discussed. The results show that with some care, the battery behavior in real-life can be reasonably predicted. This is important as two-wheelers and three-wheelers constitute well over 80 % of India's 300 million vehicles, and when converted to electric, these vehicles would not have any kind of cooling.