A simple, mild, and effective template approach has been used to produce hollow silica nanospheres with controlled sizes ranging from 40 to 150 nanometers. The obtained powders showed systematic variations in measured thermal conductivity, with values down to 0.024 W/(mK) so far, with en expressed goal to reach below 0.020 W/(mK). Surface hydrophobization was successfully performed. Thus, hollow silica nanospheres are considered to be promising building blocks for new hydrophobic, superinsulating materials.

Vacuum insulation panels (VIPs) are regarded as one of the most promising existing high performance thermal insulation solutions on the market today as their thermal performance typically range 5–10 times better than traditional insulation materials. However, the VIPs have several disadvantages such as risk of puncturing by penetration of nails and that they cannot be cut or fitted at the construction site. Furthermore, thermal bridging due to the panel envelope and load-bearing elements may have a large effect on the overall thermal performance. Finally, degradation of thermal performance due to moisture and air diffusion through the panel envelope is also a crucial issue for VIPs. In this work, laboratory investigations have been carried out by hot box measurements. These experimental results have been compared with numerical simulations of several wall structure arrangements of vacuum insulation panels. Various VIP edge and overlap effects have been studied. Measured U-values from hot box VIP large-scale experiments correspond well with numerical calculated U-values when actual values of the various parameters are used as input values in the numerical simulations.

Abstract

Detailed knowledge of electricity demand is essential for power system planning and operation. EUs 20-20-20 targets will increase the development of more energy efficient buildings as all new buildings shall be “nearly zero energy buildings” by 2020. The result from this ambition is that so-called passive buildings and nearly-net-zero-energy-buildings (nZEB), with lower energy demand, or even onsite power generation, will significantly change the way buildings are integrated in the power system. System operators must consequently prepare for changes in load profiles. However, the knowledge on the aggregated impact of nZEBs is so far limited because the actual number of such buildings is still very small. This paper contributes to this knowledge gap by estimating the aggregated effect on electricity demand profiles.

The load modelling is based on a statistical approach deriving hourly electricity load profiles of non-residential buildings based on measurements of 100 buildings. The profiles will be used as basis in further work to study the impact of a
large rollout of ZEBs on the power system.

Index Terms-- zero energy buildings (ZEB), load modelling, load
profiles, regression, non-residential buildings, and statistics.

This is a report on a study conducted in the spring of 2011 to examine the cultural and social conditions associated with rebound effects on the household level. The goal of the study was to conduct an empirical, qualitative exploration of the conditions that favour rebound effects. In economics, rebound effects are defined to occur when a measure intended to increase energy efficiency actually contributes to an increase of energy consumption. Examples of conditions that favour rebound effects include using heat pumps for cooling, leaving energy‐saving light bulbs on for longer periods or neglecting to shut them off entirely, or driving an energy efficient car more often at higher speed over longer distances.

 To shed light on rebound effects occurring on the household level, in this study we aim at contributing to a better understanding of the meanings that households attach to energy‐saving investments in general and to examine conditions that result in unexpected reductions of the effect of energy efficiency investments. The material for this study was gathered through in‐depth interviews with the representatives of 17 households in the Trondheim region. Each interview lasted about an hour. The majority of the respondents were drawn from a group of approximately 100 households that had received funding from Enova SF to procure technology for improving energy efficiency. In the interview, we asked respondents about their commitment to the environment, energy practices, energy technologies and their relationship to the energy bill and their energy supplier/utility company. In particular, to identify situations where rebound effects might arise, we examined respondents’ reports on their experiences of introducing energy efficient technology into their household, their everyday energy practices, and the ways in which this new technology forced or warranted change in their energy consumption behaviour.