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In addition to fuel cell applications, water electrolysis affords several opportunities for producing high-grade heat by utilising electrolytic hydrogen and oxygen in combustion applications. This can reduce or eliminate the atmospheric emissions associated with the combustion of conventional fuels. Importantly, net-zero heat can be produced if the electrolyser is powered by renewable electricity, whereby the output gases may be termed green hydrogen and green oxygen. This paper provides an overview of prospective applications for electrolysers in the heat sector by considering three general implementation pathways based on how the electrolytic oxygen is used.

This briefing reviews progress that was made at the 26th United Nations Climate Change Conference of the Parties (COP26) held in Glasgow, Scotland, UK over 1–12 November 2021. The context of the global climate change challenge is outlined, along with the aspirations of the major participating international groups. An overall balance sheet is provided that gives an assessment of the achievements and disappointments in the outcomes of COP26. This assessment sets a backdrop to what needs to be achieved when the Parties next meet at COP27 in Sharm El-Sheikh, Egypt in 2022 to address both immediate and longer-term climate change mitigation, adaptation and climate finance.

The use of any fuel depletes the oxygen content of the atmosphere, with one exception: hydrogen produced from water. Water electrolysis liberates oxygen from water in the precise stoichiometric ratio required to oxidise (and hence release energy from) the co-produced hydrogen. As a commercial fuel production process, electrolysis is unique in providing the oxidant as well as the fuel; electrolytic oxygen can thereby replenish the consumption of atmospheric oxygen due to hydrogen use. Furthermore, the amount of water consumed during electrolysis is reproduced when the hydrogen is oxidised. So the use of electrolysers and electrolytic hydrogen does not affect global oxygen and water resources: ‘green’ hydrogen may thus be described as the only oxygen and water balanced fuel. Conversely, the use of hydrogen derived from fossil fuels (with or without carbon capture and storage, CCS) depletes the oxygen resource and increases water vapour emissions to the atmosphere, which enhances the rate of global warming. Therefore, a worldwide multi-TW deployment of electrolysers could provide very substantial amounts of hydrogen for the energy system, and oxygen for the global ecosystem. This should be done in combination with other measures for combatting oxygen depletion (such as reducing combustion, increasing forestation, and reducing nutrient inputs to the ocean from sewage and agriculture). In this way the long-term objective should be to stabilise, or even increase slightly, the concentrations of atmospheric and aquatic oxygen, and possibly speed up the decay of atmospheric methane. Clearly the production-and-use of hydrogen derived from fossil fuels contravenes this objective, and should cease without delay.

The fundamental reasons for considering the adoption of hydrogen as a fuel, industrial feedstock and energy storage medium are presented. Hydrogen production methods are outlined, with reference to the colour prefixes used to describe different types of hydrogen. The relative greenhouse gas emissions and economics of green and blue hydrogen production are considered for achieving a ‘net zero’ climate-neutral energy system by 2050. In general, it appears that green hydrogen will soon be cheaper than blue hydrogen due to the falling costs of renewable electricity and electrolysers, then cheaper than grey hydrogen, and in the long term potentially cheaper than natural gas.

This article explores the importance of renewable hydrogen in achieving a ‘climate neutral’ energy system, which will require a large amount of renewable electricity and a very large amount of renewable hydrogen. Because of the fundamental need for energy storage to match supply and demand, a two-carrier approach needs to be adopted, where both electricity and hydrogen are derived from renewable energy. National hydrogen strategies, electrolyser deployment plans and the actions required by governments to overcome the current policy vacuum are discussed. It is recommended that a cross-sector ‘green electrons and green molecules’ strategy is taken, and that policies are developed urgently for advancing the adoption of renewable hydrogen.

Geoffrey Hammond at the University of Bath and Marcus Newborough of ITM Power review what happened at the UN climate change conference in Glasgow last year, and what the resulting ‘Glasgow climate pact’ means for global warming and climate change.

Rendering the energy system more sustainable can only be achieved through a combination of low-carbon energy production, energy efficiency, and coupling of energy sectors. In this context, Power-to-Hydrogen concepts for managing supply and demand, providing seasonal storage, and being the linking element between different sectors (electricity generation, gas grids, transport and industry), has attracted significant interest during the last decade. However, the deployment of technology is subject to legal barriers, which may differ from one region to another. On the contrary, there may be incentives to facilitate market introduction of a new technology.In this paper, an international network of experts under the umbrella of Task 38 of the International Energy Agency's Hydrogen Technology Collaboration Programme assesses the legal framework in ten countries regarding power-to-hydrogen applications. The most frequently considered pathway, from a legal standpoint, is using hydrogen for mobility applications. Only a few countries are implementing legal frameworks for diverse hydrogen applications. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Various configurations of power-to-gas system are investigated as a means for capturing excess wind power in the Emden region of Germany and transferring it to the natural gas grid or local biogas-CHP plant. Consideration is given to producing and injecting low concentration hydrogen admixtures, synthetic methane, or hydrogen/synthetic methane mixtures. Predictions based on time series data for wind generation and electricity demand indicate that excess renewable electricity levels will reach about 40 MW and 45 GW h per annum by 2020, and that it is desirable to achieve a progression in power-to-gas capacity in the preceding period. The findings are indicative for regions transitioning from medium to high renewable power penetrations. To capture an increasing proportion of the growing amount of excess renewable electricity, the following recommendations are made: implement a 4 MW hydrogen admixture plant and hydrogen buffer of 600 kg in 2018; then in 2020, implement a 17 MW hybrid system for injecting hydrogen and synthetic methane (with a hydrogen storage capacity of at least 400 kg) in conjunction with a bio-methane injection plant. The 17 MW plant will capture 68% of the available excess renewable electricity in 2020, by offering an availability to the electricity grid operator of >97% and contributing 19.1 GW h of ‘green’ gas to the gas grid.

The feasibility of implementing power-to-gas systems, to absorb surplus solar power from electricity distribution networks and carbon dioxide from biomass anaerobic digestion (AD) plant, in order to produce synthetic methane was investigated for a region of Southern Germany that has a high solar power penetration. The analysis was based on time series electricity data for 2012 from which future load profiles were computed in accordance with the expected installed capacities of solar power across the period 2015–2025. The electrolyser capacity required to absorb 20% of excess solar energy occurring within the region's low voltage network in 2025 was estimated to be 370 MW e . First order considerations of the region's gas grid, electricity network and existing AD sites suggest that such a deployment could be achieved by installing sub-MW (and some multi-MW) power-to-gas plant at several hundred AD sites.

An assessment is presented of the prospective use of micro-generation systems in conjunction with electrolysers and hydrogen stores for refuelling private bi-fuel (gasoline/hydrogen) cars with hydrogen. For a range of system sizes and three power source operating modes, predictions are made of the annual travel range on hydrogen and the associated CO2 savings. A basic system (Mode A) operating solely from the output of a photovoltaic array was found to generate sufficient hydrogen to allow a passenger vehicle with a fuel efficiency of 8.5 l/100 km (33 mpg) to travel 613 km annually per kW of PV installed. An alternative system (Mode B) that permitted network electricity to contribute to hydrogen production, provided that the CO2 emission factor of the generated hydrogen was half that of gasoline, enabled an annual travel distance of 772 km per kW of PV installed. A hybrid micro-generation system comprising a PV and micro-CHP system (Mode C), where the electricity that would otherwise be exported from the dwelling was diverted to hydrogen production, achieved a more consistent hydrogen production rate across the year. This resulted in a lower on-site storage requirement; when compared with Mode A, it provided an additional annual travel distance on hydrogen of between 1285 and 1833 km. A utility factor was employed to indicate the extent to which a system design could deliver a given daily driving distance on hydrogen across the year. High utility factors (>70%) were only achievable for modest daily driving distances (10–17 km) for the considered range of PV sizes (1.7–8.5 kW).

This paper considers the relationship between heat-saving and micro-combined heat and power (μCHP) technological interventions for reducing the carbon footprint of existing domestic dwellings within the UK housing stock. The relationship between the annual heat requirement of individual dwellings and the CO 2 savings attributable to different μCHP systems is investigated (by means of predictive modelling based on heat and power demand datasets recorded on a 1-min time base for nine dwellings). An assessment is made of the effects of various heat-saving measures upon the annual CO 2 savings predictions for candidate μCHP system implementations, when applied to ‘domestic building variants’ (as defined within the Carbon Vision TARBASE research programme). The increasing application of heat-saving interventions serves to reduce the CO 2 savings solely attributable to a μCHP system. The magnitude of this effect is a function of the μCHP system's electrical efficiency and electrical power output. For example, a 1 kW prime mover of 10% electrical efficiency is predicted to reduce annual CO 2 emissions by 72 kg CO 2 for a dwelling with an annual heat requirement of 11.9 MWh, but if the identified set of heat-saving measures is implemented first the demand falls to 5.0 MWh and the μCHP system will actually result in an emissions increase of 100 kg CO 2 p.a. By comparison, relative savings of 467 and 294 kg CO 2 p.a. are predicted if this dwelling is fitted with a 1 kW prime mover of 30% electrical efficiency. Still greater savings are predicted for higher power output systems of high efficiency, but a relatively large proportion of the generated electricity (44–75% depending on the heat and electrical demand of the dwelling) must then be exported.

The mass deployment of electrolysers, within a power system serving a region of high wind resource, as the enabling mechanism for achieving five key objectives is assessed (that is: a very high installed capacity of wind power plant (WPP); zero wind curtailment during times of low demand; a very high load factor for thermal power plant; an electricity supply of low-carbon intensity; and a hydrogen supply of low-carbon intensity). Three electrolyser implementation cases were simulated for three days characterised mainly by wind availability and emphasis was placed on maximizing the smoothness of the load profile (LF) applied to thermal power plant. If zero-carbon hydrogen is to be produced a daily load factor for thermal power plant of 90% is the upper limit, but load factors of up to 100% are achievable if a carbon intensity of 3 kgCO 2 / kgH 2 is permitted. For wind penetrations exceeding approximately 30% of system maximum demand, the electrolyser stock must include implementations close to WPP if curtailment is to be avoided. To achieve very high wind penetrations and very high load factors for thermal power plant requires a large stock of electrolysers—for the system investigated approximately 1.1 MW of electrolyser capacity is required per installed MW of wind power.

Variations in the dielectric properties of foods with applied microwave frequencies, and food composition, moisture content and temperature, were investigated. A series of equations to estimate the dielectric properties of a wide range of food materials was deduced from available experimental data and current understanding. the equations are suitable for incorporating into a numerical model to predict the transient temperature and moisture-content profiles within microwave-heated foods.

As micro-CHP systems move towards mass deployment an increasing emphasis will be placed on their effect on time-varying demands for network electricity. A 50 dwelling data set of heat and power demands was employed to investigate the implementation of various penetrations of μCHP system on the resultant electrical load profile using two control methodologies: heat-led and a proposed method for modulating the aggregate electrical load. The first caused the daily load factor of the net load profile to decrease from 42.5% to 28.6% on a January day and the after diversity maximum demand to decrease from 2.0 to 1.2 kW. The second caused the daily load factor to increase from 42.5% to 48.6% and the after diversity maximum demand to decrease from 2.0 to 0.9 kW. The extent to which these improvements in load factor can be achieved was investigated in detail and maximum resultant load factor values were identified for a day in January, April and July. Further improvements in the modulating capability of this control approach may be realised if prime movers capable of rapid start-up, shut-down and cycling can be developed. The control of micro-CHP systems in this manner offers a mechanism for managing the load at distribution transformers.

A method is proposed for estimating the electricity consumption (and associated carbon emissions) of a defined electrical-lighting configuration in an office building, accounting for the daylight contribution from windows and rooflights. Heat gains due to lighting for an average day in each month may be used to aid assessments of the effect of lighting systems on the cooling load, known to be high for office environments. For a typical 6-storey office building, annual energy savings for lighting of 56–62% and a reduction in CO 2 emissions of nearly 3 tonnes are predicted by changing the lighting and daylighting specifications for a defined “2005” scenario to those of a low-carbon “2030” scenario. The associated reduction in peak lighting-load, and hence heat gain due to lighting, is 3 W/m 2 .

Home automation systems, smart meters and broadband Internet connectivity provide excellent potential platforms for introducing advanced energy consumption displays (ECDs) in the home. These displays may be ‘central’ (one per home) or ‘local’ (specific to the location where an individual energy-use event takes place). Methods for motivating energy-saving behaviours and for presenting energy-use information on these two display types are discussed. Consideration is given to the energy units to be displayed, the method of display, how to display the information temporally, and how the display information might be categorised (by fuel, by appliance, by room, etc.). The facility to set goals via an energy consumption display is identified as a key method for motivating consumers. The presented information needs to be grouped effectively to encourage effective energy-saving efforts and several potential information groupings for local display are presented, based on a categorisation of user interaction with individual types of appliance.

This paper considers the design of energy consumption displays from a theoretical standpoint in relation to user–appliance interactions in the home. It presents the main options for display position and discusses what detailed information to display in order to promote energy saving. To guide the designer in making decisions regarding the merits of displaying appliance-specific information (ASI) and grouped appliance information (GAI) around the home, classifications are presented of appliance-associated micro-behaviours and appliance control to end-use relationships. A hybrid display approach is suggested as a most effective solution. Copyright © 2006 John Wiley & Sons, Ltd.

The effects of applying combined heat and power systems, based on Stirling engines and fuel cells, to single UK dwellings are investigated by using heat and power demand data recorded on a 1-min time base across a full year. The control regime has a major influence upon economic and CO2 savings for Stirling engine systems due to their high heat–power ratio. For the considered home, the contributions made by a 1 kWe Stirling engine system to the daily demands for heat and power ranged from 54% to 100% and from 3% to 73% respectively. Future systems based on fuel cells are predicted to achieve greater savings, because they can operate for relatively long periods during mild and warm weather without generating surplus heat. Estimates of the annual savings amount to £90/574 kg CO2 for a 1 kW Stirling engine system and £142/892 kg CO2 for a prospective 1 kW fuel cell system, when compared to a non-CHP base case of employing a condensing boiler of 90% efficiency and network electricity. These respective savings represent 9% and 16% of emissions attributable to the single UK dwelling, which is highly significant relative to other individual measures that can be deployed in the domestic sector.

The feasibility of applying combined heat and power rationale to individual homes is discussed, with particular reference to the transient variations that occur in domestic requirements for heat and power. Predicted energy-cost savings, based on simulations employing 1 min demand profiles, are presented for several prospective micro-CHP systems. The effects upon energy-cost savings of prime mover capacity and efficiency, heat-recovery efficiency, central-heating boiler efficiency, and the unit price for exporting electricity are assessed. For various configurations of a nominally 1 kWe micro-CHP system, reductions of 16-39 per cent in annual energy expenditure are identified. Carbon savings per average home of around one tonne of CO2 per annum are predicted, but actual savings will depend strongly upon transient heat-and-power demand variations, the operating mode, capacity and efficiency of the micro-CHP system, and upon the import/export interaction that the household has with the electricity distribution network. If the carbon-reduction potential of this single technical fix is to be maximized, further research attention needs to be given to define preferred implementation strategies for micro-CHP systems in the UK domestic sector.

The literature concerning the application of information-feedback methods for saving energy in the home is reviewed. Particular attention is given to electronic feedback via smart meters and displays, or “energy-consumption indicators” (ECI). Previous studies have not focused on individual appliances, but this paper presents the findings of a UK field study involving 44 households which considered domestic cooking: it compares the effectiveness of providing paper-based energy-use/saving information with electronic feedback of energy-consumption via ECIs designed specifically for this investigation. Twelve Control Group households were monitored for a period of at least 12 months and this revealed an average daily consumption for electric cooking of 1.30 kWh. Subsequently across a minimum monitoring period of 2 months, 14 out of 31 households achieved energy savings of greater than 10% and six of these achieved savings of greater than 20%. The average reduction for households employing an ECI was 15%, whereas those given antecedent information alone reduced their electricity consumption, on average, by only 3%. The associated behavioural changes and the importance of providing regular feedback during use are identified. It is recommended that further attention be given to optimising the design and assessing the use of energy-consumption indicators in the home, in order to maximise the associated energy-saving potential.

Methods for recovering high purity monomer from scrap polymer are discussed, with particular reference to poly-methyl-methacrylate (commonly known as acrylic, Perspex™, Lucite™). Depolymerisation processes based on gas-fluidised beds and novel “mechanically fluidised” beds are described. These are proposed as environmentally friendly and energy-efficient alternatives to the conventional lead-bath or “Clementi” process for recovering methyl-methacrylate from acrylic scrap.

The application of slurries containing phase change materials (consisting of hydrated hydrophilic polymeric particles) to both the storage and the transmission of thermal energy at temperatures below ambient has been investigated. Phase change due to freezing has been investigated experimentally for oil-based slurries employing hydrophilic copolymer particles in concentration of 1%, 5%, 10% and 25% (by volume). The principle findings are: 1. At temperatures above the phase transition temperature the presence of particles causes a significant increase in the measured heat transfer coefficient for concentrations ⩾10%. 2. There is a significant interaction of particles at the heat transfer surface. 3. Under high flow rate conditions with phase change occurring, the heat transfer coefficients are enhanced considerably (i.e. by about 80%) when compared with the support fluid alone or with the support fluid incorporating similar volume fractions of non-active particles.

`Energy auditing’ as a technique for obtaining a ‘snapshot’ of the energy flows in a city or urban conurbation is discussed in the context of meeting national and international targets for CO2 emissions abatement. An audit methodology is presented which addresses the key questions: Who needs to be involved in the audit? How should the city or conurbation be divided? What data are required? How might these data be obtained and then analysed? Which are the areas of significant consumption? A basis for setting local targets for reducing future energy consumption and CO2 emissions is presented. The scope for auditing major cities and conurbations in the United Kingdom is identified with reference to implementing Local Agenda 21 and satisfying CO2 emissions reduction targets.

Experiments have shown that frost growth on cold surfaces exposed to warm humid air streams can be reduced significantly by means of crosslinked hydrophilic polymeric coatings. This derives from the ability of these materials, under frosting conditions, to absorb available water, and hence retard the growth of frost when compared to an uncoated metallic surface. The extent of reduction of frost growth appeared to vary with the water absorbing potential of the polymer-coat, as well as its water content prior to frosting. In general, measurements in over two hours of testing, indicated that the reduction in frost growth rate and subsequently frost thickness lies in the range, 10–30%. The absorbed water improves the thermal conductivity of the polymeric coating. This, consequently, lowers the total thermal resistance between the air stream and the cold plate, and hence retards the frost surface temperature in its rise towards 0°C, an effect that would prolong the effective operation time of the thermal process before there is need for defrosting. Further observations made in this study tend to suggest that the nature of the frost formed with an air stream of low relative humidity (RH) differed from that resulting from a high RH air stream.

A low-emissivity oven (LEO) provides an energy-efficient alternative to a conventional domestic electric oven. A prototype domestic LEO is described and its energy performance is assessed and compared with that of a current generation domestic electric oven and previous test-rig ovens. In standard tests, the prototype achieved energy-savings of 36–57% when compared with the commercially-available oven, providing thermal performances similar to those of ‘idealised’ test-rig ovens. It is, therefore, recommended that manufacturers implement low-emissivity oven designs for domestic users as a means of speeding thermal performance, reducing energy consumption, and thereby reducing the emissions and peak electrical demands associated with domestic cooking.

The characteristics of mechanically-stimulated particle beds are reviewed with particular attention to the transfer of heat at atmospheric pressure. A mass of granular material, when vibrated in the frequency range of 20–100 Hz at an amplitude of up to 5 mm, can serve as an excellent heat transfer medium. The particles engage both in a local minor motion and an overall streaming motion which facilitates higher transfer rates than those normally encountered in gas-fluidized beds, because of the absence of the relatively low conductivity gas bubbles. Preliminary experimental findings at atmospheric pressure indicate high heat transfer coefficients of up to 1100 W/m 2 K for particle diameters of 50 d p μ m, these values being much greater than those achievable by gas fluidization, and heat transfer coefficients as high as 280 W/m 2 K at 20 mbar.

Fully hydrated crosslinked hydrophilic polymers have been subjected to freeze/thaw thermal cycling and the crystallization of water within these polymers has been monitored using a simple transient thermal method. The initially large depression of the crystallization temperature (relative to the crystallization temperature of bulk water) decreased with the number of thermal cycles. This phenomenon has been attributed to a partial breakdown of the polymer network, due probably to the thermomechanical stresses occurring during ice/water formation in the course of freeze/thawing.

Crystallization of water within crosslinked hydrophilic polymeric network structures has been investigated using a simple transient thermal method. The results imply that partial crystallization of water occurs and that there is a critical concentration below which the absorbed water would not crystallize. This suggests that water within crosslinked hydrophilic network structures may also be existing in two states, as has been reported for uncrosslinked hydrophilic systems. However, factors that may limit the quantity of crystallizable water in crosslinked hydrophilic systems are discussed in this paper.

Natural convection within a 1700 mm horizontally long, 350 mm× 350 mm square cross-sectioned oven, containing a symmetrically-positioned square-sectioned inner body, has been measured. Attention was focused on the effects that three heater configurations have on the steady-state rate of heat transfer to the rectangular-sided, 175 mm× 175 mm square cross-sectioned inner body. The radiative fluxes to each of the inner-body's surfaces have been calculated for the different configurations, using a multi-zone radiation model. Evacuating the enclosure permitted the convective component of the steady-state heat transfer to be identified. Thence, an easily applicable empirical correlation, of the form Q conv =n 1 log e Q in +n 2 was deduced for the natural-convection contribution. Overall, the proximity of the heating element to the inner body dictated the proportions of the rates of heat that are transferred by radiation and convection. For enhanced convective-heating, configurations with the heaters mounted along the lower section of the sidewall, are recommended.

A 9.5 mm-diameter, horizontal, cylindrical heater was traversed horizontally and vertically within a 750 mm long, 350 mm×350 mm square-sectioned relatively-cold enclosure for two values of the Rayleigh number, namely 7.0×104 and 1.0×105. The maximum steady-state rate of natural convection occurred when the heater was located parallel to and near a vertical wall (i.e. with 0.25

Low-emissivity ovens have linings of ee

Electrolyser-based energy management (EBM) offers a versatile means for optimising the process of harnessing energy supplies derived from variable and/or intermittent renewable resources, e.g. solar (photo-voltaic), wind, wave and tidal. In general, EBM systems consist of an electrolyser, water and gas (hydrogen and, optimally, oxygen) storage and management systems and a means of (re-) generating electricity, e.g. a fuel cell. Such systems achieve their management via energy conversion and storage, this operational principle being referred to as electricity supply-and-demand management (ESDM). Implementation of this principle offers significant advantages in the utilisation of variable and/or intermittent renewable resources, as it permits electricity generated during periods of high-availability/low-demand to be “time-shifted” for subsequent re-supply during periods of low-availability/high-demand. Furthermore, EBM systems have the important advantage over other ESDM systems that the stored form of energy is readily utilisable as a pollution-free gas supply for thermal end-uses. This reconversion route significantly enhances the overall energy-conversion efficiency. Electrolyser and fuel cells based upon proton-exchange membrane technologies are preferred because these afford considerable operational advantages over any alternatives. In this paper these advantages are expanded upon and preliminary data based on these ideas are presented.

The social-psychological aspects of energy use in UK households have been reviewed. A major survey, which focused on identifying environmental attitudes and beliefs, energy-use behaviour, ownership levels for certain appliances and their utilisation patterns, was undertaken among householders resident in the south-east of England. The results indicate that members of the general public are (i) interested in receiving information concerning household energy use and the associated environmental impact, and (ii) willing to modify their behaviour in order to reduce household energy consumption and environmental damage. Therefore, there is an urgent need to provide end-users with accurate energy-consumption and environmental-impact information, persuasively presented, to stimulate energy-rational and environmentally sustainable behaviour. For each major domestic electrical appliance, the survey data permit estimates of the variations in energy consumption per household and of the aggregate annual consumption nationally.

A novel means for managing electricity, or energy supplies derived from electricity, is proposed. This is termed electrolyser-based management (EBM) and involves energy storage. The energy is stored as the chemical potential-energy of the hydrogen/oxygen-water reaction, with the input energy-conversion being performed by an electrolyser and subsequent regeneration to electricity via, preferably, a fuel cell. Proportions of the stored hydrogen and oxygen may be employed for combustion purposes, depending upon the application. Such a system has a unique energy-management capability in being able to provide a clean electricity-derived gas supply in addition to a managed electricity output. Furthermore, EBM systems, such as these, offer considerable scope for what can be broadly termed ‘hydrogen economy’ applications.

The rational use of energy is essential for the long-term sustainability of future generations. Man's future prosperity depends upon the quality of energy education provided for all citizens, as well as the progress made by scientists and engineers in devising and applying less polluting, more energy-efficient technologies. Unfortunately, few individuals have acquired an adequate knowledge with respect to energy use and its environmental consequences, because the broad subject of ‘energy’ has not been taught in a coherent manner. In particular, the desirable evolution towards a more energy-effective society is inhibited by widespread ignorance as to exactly why and how we should become less dependent on fossil fuels. To overcome this energy ‘innocence’, ‘illiteracy’, ‘innumeracy’ or ‘apathy’, relevant energy education needs to be promulgated, with greater vigour, in a more comprehensive and coherent manner throughout our education system.

This paper describes the heat transfer attributes of vibrated particle beds, based on experimental results conducted at atmospheric pressure and under vacuum. A mechanically-fluidized bed of glass particles (of mean diameter 95, 200, 300, 450 or 700 μm) was heated by an immersed cylindrical heater and vibrated at frequencies of 20 to 100 Hz and amplitudes of 0.2 to 5 mm. The heat transfer rates encountered under different conditions reveal the proportion of cooling achieved by gas convection and by solid particle cooling. At 8 mbar, heat transfer coefficients were approximately 190 W/m 2 .K and 330 W/m 2 .K for particles of 700 μm and 95 μm respectively, while at atmospheric pressure the corresponding values were 320 W/m 2 .K and 770 W/m 2 .K.

Utilisation of electricity within the domestic sector is examined. The characteristically time-dependent behaviours of domestic consumers and their associated usages of household appliances result in ‘peaky’ daily electricity-demand curves. This is not conducive to achieving (i) a high-efficiency electricity supply, (ii) low rates of financial investment in a new generating plant or (iii) curtailing rates of pollutant emissions. A relatively energy-efficient, environmentally clean, electricity-supply system can only be realised when the total demand (i.e. the total for the domestic, commercial and industrial sectors) versus time curve does not exhibit rapid changes in gradient. In order to achieve this goal, existing and more appropriate electrical load-management techniques need to be implemented, especially for the domestic sector. Thus, opportunities for demand-side load-management are assessed together with the prospective benefits obtainable by domestic consumers and electricity-supply companies.

Electromagnetic-heating processes are reviewed. Theoretical analyses of electromagnetic-heating processes in isotropic materials of various regular geometries and with ranges of physical properties have been undertaken. The mathematical model so devised may be employed as a design tool in the development of a product/process and may thereby serve as a means for reducing the necessity for experimentation, which is usually expensive. In particular, the educational benefits of employing such a multi-purpose mathematical model, to improve the understanding of the thermal effects of electromagnetic-heating techniques, are emphasised.

The quality and quantity of life are linked inextricably with methods of harnessing and utilizing energy. Our future prosperity does not depend solely upon the progress made by scientists and engineers: it can be secured only when energy-use and energy thrift become components of the knowledge-base of the average person. At present, few individuals are so equipped, because ‘energy’ (as a subject or discipline) has not been promulgated in a coherent manner within our educational system. For example, in the UK, energy education has been treated in a disparate manner within the curricula of primary and secondary education, whilst being considered in depth only in the engineering disciplines within tertiary education. This paper reviews UK energy education in the context of creating a more energy-effective European Community. In particular, the UK's provision of tertiary energy education is discussed. An analysis is presented of the case for coordinating education within each built-environment discipline (ie, architecture, building technology, building surveying and building-services engineering) around the topic of ‘energy efficiency’.

The evolution of energy education within UK schools and the inherent problems associated with teaching the subject of ‘energy’ to children are reviewed. Unfortunately the provision of energy education, at all levels, is inadequate: cohesion is often poor and lack of continuity sometimes occurs. Macro-level recommendations are proferred to enhance the quality of energy-education provision within primary and secondary schools.

Experimental analyses of the thermal performances of (i) various heating-element configurations, (ii) a low-emissivity internal oven-lining, (iii) control systems for regulating internal air temperatures, and (iv) various thermal-insulation systems for an oven have been undertaken. Overall, a substantial increase in the thermal efficiency was achieved, i.e. from 17 to 26%. This compares favourably with the value of 13%, as measured for a typical commercially available domestic oven.

The utilisation of household equipment (i.e. for space-heating, water-heating, cooking, washing, cleaning, drying, food-preservation, entertainment, and personal care) influences significantly the UK's peak electrical demand. By developing intelligent load-management facilities for domestic dwellings, which do not infringe adversely on personal lifestyles, peak demands may be reduced. A significant saving in the predicted national requirement for reserve power-generating plant should thereby the achieved. Such home-automation systems would also help facilitate the introduction of a responsive time-of-use electricity-pricing system, which passes on the real-time cost of power generation to the end user. Once realised, this would encourage consumers to be more energy-conscious when purchasing and using electrical equipment.

Single-phase ‘shaded-pole’ induction motors, which are commonly employed for driving small (i.e.

Three types of commercially-available electric (415 V, three-phase) catering hobs, namely the ‘induction’, ‘halogen’ and conventional resistance hot plates have been tested. For each, assessments have been made of: 1. (i) the rate of energy consumption; 2. (ii) controllability and responsiveness; 3. (iii) thermal safety; 4. (iv) environmental comfort; and 5. (v) purchase price and running costs. The hobs were heavy-duty cooking systems of similar overall size and maximum power output. ‘Off-the-shelf’ pans of near-identical geometry were employed in conjunction with the appliances in order to permit comparisons to be made between the performances of different pan materials. The performance of the induction hob was superior with respect to energy efficiency, cooking speed, controllability and thermal safety. However, in economic terms, the halogen hob offers an attractive compromise between the other appliances. Purchasers of the induction and halogen hobs would be able to achieve pay-back periods of 2·8 and 0·5 years respectively when used to replace a resistance hob in an ‘all electric’ industrial-catering kitchen, in which approximately 250 traditional lunches are prepared each day.

An ultrasound probe includes a cross-linked hydrophilic material as an integral couplant, wherein the hydrophilic material is capable of transmitting a frequency in the range of 5 to 20 MHz, and wherein the attenuation of the transmission is less than 1.5 dB.mm −1 at 5 MHz. For example, the invention provides a wheel-type probe, where the hydrophilic material 19 forms the tire.

The electricity demand signatures of individual UK dwellings, and of the main types of domestic appliance employed by households, have been collected and analysed. Means for modulating these electricity demands have been investigated experimentally. Peak power reductions of up to 60% have been achieved by developing 'load conscious' control algorithms for individual cooking and washing appliances, without adversely affecting their performances. Peak avoidance via an integrated control philosophy (for managing a household's coincident peak power demands) and thermal storage, have also been assessed. If widely applied in UK housing, the findings of this investigation could serve to substantially smooth local and national electricity demand profiles.

Cooking appliances are notoriously wasteful of energy. The present survey and investigations outline the history and behaviours of the main forms of cooking equipment available and indicate the energy efficiencies of the various designs. Improvements regarding equipment design, cooking techiques and consumer education are suggested from an energy-thrift perspective.

A simple low-cost digital photogrammetric system for interpreting Mach-Zehnder interferograms is described. The associated software permits the rates of heat transfer occurring within test cells of two-dimensional section to be deduced. The interferograms may be analysed quantitatively much more rapidly, and with less supervision, via this facility, than by the laborious conventional technique of using a travelling microscope.