Using surplus nuclear power for hydrogen mobility and power-to-gas in France

Opportunities exist to utilise excess electricity from renewable and nuclear power generation for producing hydrogen. France in particular has a very high penetration of nuclear power plant, some of which is regularly turned down to follow the electricity demand profile. This excess nuclear electricity could be utilised via the electrolysis of water to satisfy the emerging French market for low-carbon hydrogen (principally for mobility applications and the injection of synthetic gas into the natural gas grid). The described analysis examines the use of electrolysers to progressively ‘valley fill’ nuclear load profiles and so limit the need for turning down nuclear plant in France. If an electrolyser capacity of approximately 20 GW is installed, there is already sufficient excess nuclear electricity available now to meet the predicted hydrogen mobility fuel demand for 2050, plus achieve a 5% concentration (by volume) of hydrogen in the gas grid, plus produce approximately 33 TWh p.a. of synthetic methane (via the methanation of hydrogen with carbon dioxide). The pattern of electrolyser utilisation requires operation mostly at a variable part load condition, necessitating the adoption of flexible, efficient, rapid response electrolysers. The proposed approach more fully utilises the substantial existing nuclear power assets of France and provides an additional pathway to renewables for reducing the CO2 emissions of hydrogen production

Techno-Economic Modelling Of A Utility-Scale Redox Flow Battery System

A one-dimensional numerical model has been developed for redox flow battery (RFB) systems with bipolar flow-by electrodes, soluble redox couples, and recirculating batch operation. Overpotential losses were estimated from the Butler-Volmer equation, accounting for mass-transfer. The model predicted the variation in concentration and current along the electrode and determined the charge-discharge efficiency, energy density, and power density. The model was validated using data obtained from a pilot-scale polysulphide-bromine (PSB) system commercialized by Regenesys Technologies (UK) Ltd. The model was able to predict cell performance, species concentration, current distribution, and electrolyte deterioration for the Regenesys system. Based on 2006 prices, the system was predicted to make a net loss of 0.45 p kWh−1 at an optimum current density of 500 A m−2 and an energy efficiency of 64%. The economic viability was found to be strongly sensitive to the kinetics, capital costs, and the electrical energy price differential

Some basic crafts based on fine arts standards for the elementary grades

Thesis (M.A.)--Boston University, 1949. This item was digitized by the Internet Archive

Hybrid hydrogen-battery systems for renewable off-grid telecom power

Off-grid hybrid systems, based on the integration of hydrogen technologies (electrolysers, hydrogen stores and fuel cells) with battery and wind/solar power technologies, are proposed for satisfying the continuous power demands of telecom remote base stations. A model was developed to investigate the preferred role for electrolytic hydrogen within a hybrid system; the analysis focused on powering a 1 kW telecom load in three locations of distinct wind and solar resource availability. When compared with otherwise equivalent off-grid renewable energy systems employing only battery energy storage, the results show that the integration of a 1 kW fuel cell and a 1.6 kW electrolyser at each location is sufficient, in combination with a hydrogen storage capacity of between 13 and 31 kg, to reduce the required battery capacity by 54–77%, to increase the minimum state-of-charge from 37 to 55% to >81.5% year-round despite considerable seasonal variation in supply, and to reduce the amount of wasted renewable power by 55–79%. For the growing telecom sector, the proposed hybrid system provides a ‘green’ solution, which is preferable to shipping hydrogen or diesel to remote base stations

Project Dawdler: a Proposal in Response to a Low Reynolds Number Station Keeping Mission

In direct response to Request for Proposals: Flight at very low Reynolds numbers - a station keeping mission, the members of Design Squad E present Project Dawdler: a remotely-piloted airplane supported by an independently controlled take-off cart. A brief introduction to Project Dawdler's overall mission and design, is given. The Dawdler is a remotely-piloted airplane designed to fly in an environmentally-controlled closed course at a Reynolds number of 10(exp 5) and at a cruise velocity of 25 ft/s. The two primary goals were to minimize the flight Reynolds number and to maximize the loiter time. With this in mind, the general design of the airplane was guided by the belief that a relatively light aircraft producing a fairly large amount of lift would be the best approach. For this reason the Dawdler utilizes a canard rather than a conventional tail for longitudinal control, primarily because the canard contributes a positive lift component. The Dawdler also has a single vertical tail mounted behind the wing for lateral stability, half of which is used as a rudder for yaw control. Due to the fact that the power required to take-off and climb to altitude is much greater than that required for cruise flight and simple turning maneuvers, it was decided that a take-off cart be used. Based on the current design, there are two unknowns which could possibly threaten the success of Project Dawdler. First, the effect of the fully-movable canard with its large appropriation of total lift on the performance of the plane, and secondly, the ability of the take-off procedure to go as planned are examined. These are questions which can only be answered by a prototype

Off-grid solar-hydrogen generation by passive electrolysis

A novel embodiment of a polymer electrolyte membrane (PEM) electrolyser is presented as a means for producing hydrogen off-grid by the efficient absorption of the time-varying power output of a solar photovoltaic (PV) panel or array. The balance-of-plant power load was minimised using passive design principles to ensure efficient operation under cloudy, sunset and wintry conditions. Heat generated during the electrolysis process is stored when appropriate to significantly enhance the efficiency of hydrogen production after a period of darkness. A prototype field trial demonstrated the electrolyser's ability to track closely the highly variable output of the PV year-round under a wide range of operating conditions. Hydrogen yields for various geographical locations were estimated to vary from 25 to 65 kg p.a. for a 1.6 kW electrolyser with fixed-tilt PV panels depending on local levels of solar insolation. This could be increased to over 100 kg p.a. by employing a PV panel of greater capacity and a battery for absorbing the peak generation and then discharging it overnight to the electrolyser

1863-01-27 Seth Scamman recommends John Little for promotion

https://digitalmaine.com/cw_me_3rd_regiment_corr/1417/thumbnail.jp

Too Many Cooks Don\u27t Always Spoil the Broth! The Library Research Starter Kit: A Creative Collaboration

We adapted the Library Research Starter Kit from Clark College’s IRIS 4-2. We modified the recipe to suit the needs and tastes of our customers. Customers are welcome to modify the recipe further at home