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

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

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

Equipment management trial : TAHI summary

The Equipment Management (EM) trial was one of the practical initiatives conceived and implemented by members of The Application Home Initiative (TAHI) with strong support from the DTI, to demonstrate the feasibility of interoperability between white and brown goods, and other domestic equipment. The trial ran from October 2002 to June 2005, over which period it achieved its core objectives through the deployment in early 2005 of an integrated system in trials in 15 occupied homes. Prior to roll out into the field, the work was underpinned by soak testing, validation, laboratory experiments, case studies, user questionnaires, simulations and other research, conducted in a single demonstration home in Loughborough, as well as in Universities in the East Midlands and Scotland. The trial was conducted against a backdrop of continual commercial change. Despite this difficult operating environment, the trial met its objectives, although not entirely as envisaged initially – a tribute to the determination of the trial’s membership, the strength of its formal governance and management processes, and especially, the financial support of the dti. The equipment on trial featured a central heating/hot water boiler, washing machine, security system, gas alarm and utility meters, all connected to a home gateway, integrated functionally and presented to the users via a single interface. The trial met its principal objective to show that by connecting appliances to each other and to a support system, benefits in remote condition monitoring, maintenance, appliance & home controls optimisation and convenience to the customer & service supplier could be provided. The EM trial identified exciting opportunities for the UK’s domestic white and brown goods manufacturing sector. Despite the relative immaturity of some of the enabling technologies people seem interested in the use of smart home devices to improve their quality of life or just generally make things easier at home in their busy schedules. Whilst the enabling technology behind future smart homes is being developed at a rapid pace, it is the intelligent application and integration of this technology that will make the difference to the home consumer. Just because the technology provider can make a ‘useful’ device it does not necessarily mean that the consumer actually wants to buy the ‘new’ invention. The EM trial has successfully shown where certain technology can be deployed successfully and also identified areas where further work is required

Equipment management trial : final report

Executive Summary The Equipment Management (EM) trial was one of the practical initiatives conceived and implemented by members of The Application Home Initiative (TAHI) to demonstrate the feasibility of interoperability between white and brown goods, and other domestic equipment. The trial ran from October 2002 to June 2005, over which period it achieved its core objectives through the deployment in early 2005 of an integrated system in trials in 15 occupied homes. Prior to roll out into the field, the work was underpinned by soak testing, validation, laboratory experiments, case studies, user questionnaires, simulations and other research, conducted in a single demonstration home in Loughborough, as well as in Universities in the East Midlands and Scotland. Throughout its life, the trial faced significant membership changes, which had a far greater impact than the technical issues that were tackled. Two blue chip companies withdrew at the point of signing the collaborative agreement; another made a major change in strategic direction half way through and withdrew the major portion of its backing; another corporate left at this point, a second one later; one corporate was a late entrant; the technical leader made a boardroom decision not to do the engineering work that it had promised; one company went into liquidation; another went up for sale whilst others reorganised. The trial was conducted against this backdrop of continual commercial change. Despite this difficult operating environment, the trial met its objectives, although not entirely as envisaged initially – a tribute to the determination of the trial’s membership, the strength of its formal governance and management processes, and especially, the financial support of the dti. The equipment on trial featured a central heating/hot water boiler, washing machine, security system, gas alarm and utility meters, all connected to a home gateway, integrated functionally and presented to the users via a single interface. The trial met its principal objective to show that by connecting appliances to each other and to a support system, benefits in remote condition monitoring, maintenance, appliance & home controls optimisation and convenience to the customer & service supplier could be provided. This is one of two main reports that form the trial output (the other, the Multi Home Trial Report, is available to EM Trial members only as it contains commercially sensitive information). A supporting library of documents is also available and is held in the virtual office hosted by Loughborough University Centre for the Integrated Home Environment

Decentralized Energy Supply and Electricity Market Structures

Small decentralized power generation units (DG) are politically promoted because of their potential to reduce GHG-emissions and the existing dependency on fossil fuels. A long term goal of this promotion should be the creation of a level playing field for DG and conventional power generation. Due to the impact of DG on the electricity grid infrastructure, future regulation should consider the costs and benefits of the integration of decentralized energy generation units. Without an adequate consideration, the overall costs of the electricity generation system will be unnecessarily high. The present paper analyses, based on detailed modelling of decentralized demand and supply as well as of the overall system, the marginal costs or savings resulting from decentralized production. Thereby particular focus is laid on taking adequately into account the stochasticity both of energy demand and energy supply. An efficient grid pricing system should then remunerate long-term grid cost savings to operators of decentralized energy production or/and charge long-term additional grid costs to these operators. With detailed models of decentralized demand and supply as well as the overall system, the marginal costs or savings resulting from decentralized production are determined and their dependency on characteristics of the grid and of the decentralized supply are discussed

Electronically commutated direct-current motor for driving tube-axial fans: A cost-effective design

Single-phase [`]shaded-pole' induction motors, which are commonly employed for driving small (i.e.