Estimating direct and indirect rebound effects for UK households

Energy efficiency improvements by households lead to rebound effects that offset the potential energy and emissions savings. Direct rebound effects result from increased demand for cheaper energy services, while indirect rebound effects result from increased demand for other goods and services that also require energy to provide. Research to date has focused upon the former, but both are important for climate change. This study estimates the combined direct and indirect rebound effects from seven measures that improve the energy efficiency of UK dwellings. The methodology is based upon estimates of the income elasticity and greenhouse gas (GHG) intensity of 16 categories of household goods and services, and allows for the embodied emissions of the energy efficiency measures themselves. Rebound effects are measured in GHG terms and relate to the adoption of these measures by an average UK household. The study finds that the rebound effects from these measures are typically in the range 5-15% and arise mostly from indirect effects. This is largely because expenditure on gas and electricity is more GHG-intensive than expenditure on other goods and services. However, the anticipated shift towards a low carbon electricity system in the UK may lead to much larger rebound effects

Life-cycle assessment of a 100% solar fraction thermal supply to a European apartment building using water-based sensible heat storage

Providing 100% of a building’s heating and hot water using a solar thermal system in a European climate has been shown to be both practically feasible and functionally successful for a new apartment building in Switzerland. The research conducted a life cycle assessment of the solar thermal system and compared the results with an air-source heat-pump, ground-source heat pump, natural gas furnace, oil furnace and a wood-pellet furnace. Using a range of lifetime scenarios it was found that the solar thermal system displays potentially significant advantages over all other systems in terms of reductions for purchased primary energy (from 84 to 93%) and reductions in GHG emissions (from 59 to 97%). However, due to the heavy industrial processes and the particular metals used in manufacturing, the solar thermal system was shown to have a higher demand for resources which, in relation to the natural gas system, can be by a factor of almost 38. Potential impacts on ecosystem quality were marginally worse than for the heat-pump and fossil fuel systems due to resource use impacts whilst potential human health impacts were similar to the heat pump systems but better than the fossil and biomass fuelled systems

A comparison of calculated and subjective thermal comfort sensation in home and office environment

This study was conducted to investigate the accuracy of the PMV model in residential buildings in UK and to find out whether a true “context effect” exists in explaining discrepancies between predicted and observed thermal sensation of occupants. Sixteen participants were subjected to a thermal comfort study at both their homes and office. Each subject voted on their thermal sensation while air and mean radiant temperature, air velocity and relative humidity were recorded. The comparison of reported thermal sensation and those predicted using ISO 7730 showed that in general PMV under predicts the thermal sensation of occupants in both environments. The neutral temperatures found in homes and offices were respectively 3ºC and 2.5ºC lower than those predicted using ISO 7730. Together with 0.2ºC difference found between reported neutral temperatures at homes and offices, this suggests that there is a true context effect affecting occupants’ thermal sensation in different environments

The nature of domestic electricity-loads and effects of time averaging on statistics and on-site generation calculations

This paper describes exploratory analyses of domestic electricity-profiles recorded at a high time resolution of 1 min on eight houses. It includes a detailed analysis of the effects of time averaging. For dwellings with on-site generation, such as micro-CHP, a better understanding of electricity profiles is important for the economic analysis of systems, and to examine the effects of widespread onsite generation on local electricity-networks. Most load data are available at half-hour intervals; averaging data over periods longer than a minute is shown to under-estimate the proportions of both export and import. The frequency distribution of loads is shown to be highly skewed, with varying distributions and an average load factor of 0.1. Further study is needed to develop more general relationships for a large sample of houses, to apply in design and research

Raising efficiency in photovoltaic systems : high resolution monitoring and performance analysis

EThOS - Electronic Theses Online ServiceGBUnited Kingdo

The Picture Theory of Disability

This thesis argues that the nature of disability is, currently, fundamentally misunderstood. Current approaches to disability are nounal and seek to determine the locus of disability with the intention of better understanding the phenomenon of disability. In contrast, this thesis offers an adverbial perspective on disability and shows how disability is experienced as an increased and personally irremediable impediment to daily-living tasks or broader goals. This thesis holds that impediment is not a function of either biological individuality or the Social, but of a specific relation between the individual and their environment. The following delineates the Picture Theory of Disability — a mechanism for the evaluation of the experience of disability and a heuristic device for the proper interpretation of disability. The theory is born of Humean sentimentalism and elements of Wittgenstein’s Picture Theory of Language, and shows when, where, and how disability is experienced.

A simple model of domestic PV systems and their integration with building loads

Photovoltaic systems can reduce the CO2 emissions associated with the consumption of electricity in dwellings. One key issue that affects both the economic case for home installation and the integration with the mains electricity grid is the match between the instantaneous production and demand for power. This initial study considers a sample of 10 dwellings which were monitored under the UK Government’s Photovoltaic Domestic Field Trial. A simple PV system model is introduced and used to examine the variations in the balance between the imported and exported electricity of the monitored households. There are cases where a large proportion of the electricity generated by a PV system is be used directly by the household and instead is exported to the mains electricity grid. The possibility of using the model explore the effects of PV system size on the import and export balance, and the benefits of sharing production and consumption between nearby dwellings, is discussed