Energy performance ratings and house prices in Wales: an empirical study

This paper investigates the price effect of EPC ratings on the residential dwelling prices in Wales. It examines the capitalisation of energy efficiency ratings into house prices using two approaches. The first adopts a cross-sectional framework to investigate the effect of EPC band (and EPC rating) on a large sample of dwelling transactions. The second approach is based on a repeat-sales methodology to examine the impact of EPC band and rating on house price appreciation. The results show that, controlling for other price influencing dwelling characteristics, EPC band does affect house prices. This observed influence of EPC on price may not be a result of energy performance alone; the effect may be due to non-energy related benefits associated with certain types, specifications and ages of dwellings or there may be unobserved quality differences unrelated to energy performance such as better quality fittings and materials. An analysis of the private rental segment reveals that, in contrast to the general market, low-EPC rated properties were not traded at a significant discount, suggesting different implicit prices of potential energy savings for landlords and owner-occupiers.

Energy performance ratings and house prices in Wales: an empirical study

This paper investigates the effect of Energy Performance Certificate (EPC) ratings on residential prices in Wales. Drawing on a sample of approximately 192,000 transactions, the capitalisation of energy efficiency ratings into house prices is investigated using two approaches. The first adopts a cross-sectional framework to investigate the effect of EPC rating on price. The second approach applies a repeat-sales methodology to investigate the impact of EPC rating on house price appreciation. Statistically significant positive price premiums are estimated for dwellings in EPC bands A/B (12.8%) and C (3.5%) compared to houses in band D. For dwellings in band E (−3.6%) and F (−6.5%) there are statistically significant discounts. Such effects may not be the result of energy performance alone. In addition to energy cost differences, the price effect may be due to additional benefits of energy efficient features. An analysis of the private rental segment reveals that, in contrast to the general market, low-EPC rated dwellings were not traded at a significant discount. This suggests different implicit prices of potential energy savings for landlords and owner-occupiers.

The energy cycle and structural evolution of cyclones over southeastern South America in three case studies

In this paper, the Lorenz energy cycle over a limited area was applied for three cyclones with different origins and evolutions, where each of them was formed in an important cyclogenetic region near southeastern South America. The synoptic conditions and energetics were analyzed during each system`s life cycle and showed important relationships between their energy cycle and the evolution of their vertical structure. In the case of the weak baroclinic cyclone which formed on Brazil`s south-southeastern coast, the analysis showed that it originated through a midlevel cutoff low with contribution from barotropic instability. Its evolution would indicate potential transition to a hybrid system if the convective activity were stronger. The system that occurred in the La Plata River mouth had features of an oceanic bomb-type cyclogenesis and showed an important contribution from the available potential energy generation term through the latent heat release by the convection. Meanwhile, the system of the southern Argentina coast presented a classical baroclinic development of extratropical cyclogenesis in the energy cycle, from the wave amplification up to the final occlusion of the associated frontal system. These analyses revealed that the development of some cyclones that occur in eastern South America can present different mechanisms that are not related to the classical extratropical cyclogenesis.

A comparative study of the low energy HD plus o-/p-H-2 rotational excitation/de-excitation collisions and elastic scattering

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Ultracold collisions between two light indistinguishable diatomic molecules: Elastic and rotational energy transfer in HD plus HD

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Energy efficiency for standard penetration tests

The need for standardization of the measured blow count number N-spt into a normalized reference energy value is now fully recognized. The present paper extends the existing theoretical approach using the wave propagation theory as framework and introduces an analysis for large displacements enabling the influence of rod length in the measured N-spt values to be quantified. The study is based on both calibration chamber and field tests. Energy measurements are monitored in two different positions: below the anvil and above the sampler. Both experimental and numerical results demonstrate that whereas the energy delivered into the rod stem is expressed as a ratio of the theoretical free-fall energy of the hammer, the effective sampler energy is a function of the hammer height of fall, sampler permanent penetration, and weight of both hammer and rods. Influence of rod length is twofold and produces opposite effects: wave energy losses increase with increasing rod length and in a long rod composition the gain in potential energy from rod weight is significant and may partially compensate measured energy losses. Based on this revised approach, an analytical solution is proposed to calculate the energy delivered to the sampler and efficiency coefficients are suggested to account for energy losses during the energy transference process.

Final state and thermodynamics of a dark energy universe

As it follows from the classical analysis, the typical final state of a dark energy universe where a dominant energy condition is violated is a finite-time, sudden future singularity (a big rip). For a number of dark energy universes (including scalar phantom and effective phantom theories as well as specific quintessence models) we demonstrate that quantum effects play the dominant role near a big rip, driving the universe out of a future singularity (or, at least, moderating it). As a consequence, the entropy bounds with quantum corrections become well defined near a big rip. Similarly, black hole mass loss due to phantom accretion is not so dramatic as was expected: masses do not vanish to zero due to the transient character of the phantom evolution stage. Some examples of cosmological evolution for a negative, time-dependent equation of state are also considered with the same conclusions. The application of negative entropy (or negative temperature) occurrence in the phantom thermodynamics is briefly discussed.

Energy and hydraulic efficiency in conventional water supply systems

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

The feasibility of using wind energy for rural populations lacking electric power in Brazil

In the wake of current global image involving environmental impacts, the use of wind power has had a remarkable growth in recent years as a technique for generating electricity. In fact, it is a source featuring strong dissemination of technology which provides decrease in costs and a greater access to low-income electricity. PROINFA (Incentive Program for Alternative Energy Sources) promotes a greater diffusion of new technologies for power generation, in particular wind-produced. Due to such a scenario on the exploitation of such energy source, current analysis discusses strategies for the development of domestic wind technology and the implications for electricity-lacking rural areas. Analysis shows a similar behavior between rural populations lacking electricity and the amount of potential energy available in the region. It is expected that this assay will contribute towards the establishment of public policies for wind-energy parks on rural farms in the North and Northeast regions of Brazil.

Global Search for Minimum Energy (H2O)n Clusters, n = 3−5

The Gaussian-3 (G3) model chemistry method has been used to calculate the relative ΔG° values for all possible conformers of neutral clusters of water, (H2O)n, where n = 3−5. A complete 12-fold conformational search around each hydrogen bond produced 144, 1728, and 20 736 initial starting structures of the water trimer, tetramer, and pentamer. These structures were optimized with PM3, followed by HF/6-31G* optimization, and then with the G3 model chemistry. Only two trimers are present on the G3 potential energy hypersurface. We identified 5 tetramers and 10 pentamers on the potential energy and free-energy hypersurfaces at 298 K. None of these 17 structures were linear; all linear starting models folded into cyclic or three-dimensional structures. The cyclic pentamer is the most stable isomer at 298 K. On the basis of this and previous studies, we expect the cyclic tetramers and pentamers to be the most significant cyclic water clusters in the atmosphere.

Using the Morse Potential to Understand Reaction Coördinates using Maple

The interactions employed in the “linear” reaction A(g)+BC(g) -> AB(g) + C(g) in a “one dimensional world” can be used to illustrate the “reaction coördinate”, using Maple, in a manner which allows students to inspect potential energy surfaces, make contour maps of those surfaces, and conceptually construct the “reaction coördinate” by tracing the local minimum path on the surface created.“one dimensional world” can be used to illustrate the “reaction coördinate”, using Maple, in a manner which allows students to inspect potential energy surfaces, make contour maps of those surfaces, and conceptually construct the “reaction coördinate” by tracing the local minimum path on the surface created.

The modelling of energy efficient drying for DSM (BL)

This thesis investigates the modelling of drying processes for the promotion of market-led Demand Side Management (DSM) as applied to the UK Public Electricity Suppliers. A review of DSM in the electricity supply industry is provided, together with a discussion of the relevant drivers supporting market-led DSM and energy services (ES). The potential opportunities for ES in a fully deregulated energy market are outlined. It is suggested that targeted industrial sector energy efficiency schemes offer significant opportunity for long term customer and supplier benefit. On a process level, industrial drying is highlighted as offering significant scope for the application of energy services. Drying is an energy-intensive process used widely throughout industry. The results of an energy survey suggest that 17.7 per cent of total UK industrial energy use derives from drying processes. Comparison with published work indicates that energy use for drying shows an increasing trend against a background of reducing overall industrial energy use. Airless drying is highlighted as offering potential energy saving and production benefits to industry. To this end, a comprehensive review of the novel airless drying technology and its background theory is made. Advantages and disadvantages of airless operation are defined and the limited market penetration of airless drying is identified, as are the key opportunities for energy saving. Limited literature has been found which details the modelling of energy use for airless drying. A review of drying theory and previous modelling work is made in an attempt to model energy consumption for drying processes. The history of drying models is presented as well as a discussion of the different approaches taken and their relative merits. The viability of deriving energy use from empirical drying data is examined. Adaptive neuro fuzzy inference systems (ANFIS) are successfully applied to the modelling of drying rates for 3 drying technologies, namely convective air, heat pump and airless drying. The ANFIS systems are then integrated into a novel energy services model for the prediction of relative drying times, energy cost and atmospheric carbon dioxide emission levels. The author believes that this work constitutes the first to use fuzzy systems for the modelling of drying performance as an energy services approach to DSM. To gain an insight into the 'real world' use of energy for drying, this thesis presents a unique first-order energy audit of every ceramic sanitaryware manufacturing site in the UK. Previously unknown patterns of energy use are highlighted. Supplementary comments on the timing and use of drying systems are also made. The limitations of such large scope energy surveys are discussed.

Distance Distributions and Energy of Designs in Hamming Spaces

We obtain new combinatorial upper and lower bounds for the potential energy of designs in q-ary Hamming space. Combined with results on reducing the number of all feasible distance distributions of such designs this gives reasonable good bounds. We compute and compare our lower bounds to recently obtained universal lower bounds. Some examples in the binary case are considered.

A kinetic energy budget and internal instabilities in the Fine Resolution Antarctic Model

An energy analysis of the Fine Resolution Antarctic Model (FRAM) reveals the instability processes in the model. The main source of time-mean kinetic energy is the wind stress and the main sink is transfer to mean potential energy. The wind forcing thus helps maintain the density structure. Transient motions result from internal instabilities of the Bow rather than seasonal variations of the forcing. Baroclinic instability is found to be an important mechanism in FRAM. The highest values of available potential energy are found in the western boundary regions as well as in the Antarctic Circumpolar Current (ACC) region. All subregions with predominantly zonal flow are found to be baroclinically unstable. The observed deficit of eddy kinetic energy in FRAM occurs as a result of the high lateral friction, which decreases the growth rates of the most unstable waves. This high friction is required for the numerical stability of the model and can only be made smaller by using a finer horizontal resolution. A grid spacing of at least 10-15 km would be required to resolve the most unstable waves in the southern part of the domain. Barotropic instability is also found to be important for the total domain balance. The inverse transfer (that is, transfer from eddy to mean kinetic energy) does not occur anywhere, except in very localized tight jets in the ACC. The open boundary condition at the northern edge of the model domain does not represent a significant source or sink of eddy variability. However, a large exchange between internal and external mode energies is found to occur. It is still unclear how these boundary conditions affect the dynamics of adjacent regions.

Numerical method for predicting the elastic lateral distortional buckling moment of a mono-symmetric beam with web openings

When used as floor joists, the new mono-symmetric LiteSteel beam (LSB) sections require web openings to provide access for inspections and various services. The LSBs consist of two rectangular hollow flanges connected by a slender web, and are subjected to lateral distortional buckling effects in the intermediate span range. Their member capacity design formulae developed to date are based on their elastic lateral buckling moments, and only limited research has been undertaken to predict the elastic lateral buckling moments of LSBs with web openings. This paper addresses this research gap by reporting the development of web opening modelling techniques based on an equivalent reduced web thickness concept and a numerical method for predicting the elastic buckling moments of LSBs with circular web openings. The proposed numerical method was based on a formulation of the total potential energy of LSBs with circular web openings. The accuracy of the proposed method’s use with the aforementioned modelling techniques was verified through comparison of its results with those of finite strip and finite element analyses of various LSBs.