Abstract: This paper proposes a linear model for optimizing
domestic energy consumption in Romania. The particularity of the
model is that it is putting in competition both tangible technologies
and thermal insulation projects with different financing modes.
The model is optimizing the energy system by minimizing the
global discounted cost in household sector, by integrating residential
lighting, space heating, hot water, combined space heating – hot
water, as well as space cooling, in a monolithic model. Another
demand sector included is the passenger transport.
This paper focuses on space heating part, analyzing technical and
economic issues related to investment decisions to envelope and
insulate buildings, in order to minimize energy consumption.
Abstract: Rice straw pellets are a promising fuel as a renewable
energy source. Financial analysis is needed to make a utilization
system using rise straw pellets financially feasible, considering all
regional conditions including stakeholders related to the collection and
storage, production, transportation and heat utilization. We conducted
the financial analysis of feasibility for a heat utilization system using
rice straw pellets which has been developed for the first time in
Nanporo, Hokkaido, Japan. Especially, we attempted to clarify the
effect of factors required for the system to be financial feasibility, such
as the heating energy demand and collection and storage method of
rice straw. The financial feasibility was found to improve when
increasing the heating energy demand and collecting wheat straw in
August separately from collection of rice straw in November because
the costs of storing rice straw and producing pellets were reduced.
However, the system remained financially unfeasible. This study
proposed a contractor program funded by a subsidy from Nanporo
local government where a contracted company, instead of farmers,
collects and transports rice straw in order to ensure the financial
feasibility of the system, contributing to job creation in the region.
Abstract: As a simple to method estimate the plant heating energy
capacity of an apartment complex, a new load calculation method has
been proposed. The method which can be called as unit building
method, predicts the heating load of the entire complex instead of
summing up that of each apartment belonging to complex.
Comparison of the unit heating load for various floor sizes between the
present method and conventional approach shows a close agreement
with dynamic load calculation code. Some additional calculations are
performed to demonstrate it-s application examples.
Abstract: Certifications such as the Passive House Standard aim to reduce the final space heating energy demand of residential buildings. Space conditioning, notably heating, is responsible for nearly 70% of final residential energy consumption in Europe. There is therefore significant scope for the reduction of energy consumption through improvements to the energy efficiency of residential buildings. However, these certifications totally overlook the energy embodied in the building materials used to achieve this greater operational energy efficiency. The large amount of insulation and the triple-glazed high efficiency windows require a significant amount of energy to manufacture. While some previous studies have assessed the life cycle energy demand of passive houses, including their embodied energy, these rely on incomplete assessment techniques which greatly underestimate embodied energy and can lead to misleading conclusions. This paper analyses the embodied and operational energy demands of a case study passive house using a comprehensive hybrid analysis technique to quantify embodied energy. Results show that the embodied energy is much more significant than previously thought. Also, compared to a standard house with the same geometry, structure, finishes and number of people, a passive house can use more energy over 80 years, mainly due to the additional materials required. Current building energy efficiency certifications should widen their system boundaries to include embodied energy in order to reduce the life cycle energy demand of residential buildings.
Abstract: The UK Government has emphasized the role of Local Authorities as a key player in its flagship residential energy efficiency strategies, by identifying and targeting areas for energy efficiency improvements. Residential energy consumption in England is characterized by significant geographical variation in energy demand, which makes centralized targeting of areas for energy efficiency intervention difficult. This paper draws on research which aims to understand how demographic, social, economic, urban form and climatic factors influence the geographical variations in English residential gas consumption. The paper reports the findings of a multiple regression model that shows how 64% of the geographical variation in residential gas consumption is accounted for by variations in these factors. Results from this study, after further refinement and validation, can be used by Local Authorities to identify areas within their boundaries that have higher than expected gas consumption, these may be prime targets for energy efficiency initiatives.
Abstract: This paper presents the modeling results of an
innovative system for the temperature control in the interior
compartment of a stationary automobile facing the solar energy from
the sun. A very thin layer of PCM inside a pouch placed in the
ceiling of the car in which the heating energy is absorbed and release
with melting and solidification of phase change materials. As a result
the temperature of the car interior is maintained in the comfort
condition. The amount of required PCM has been calculated to be
about 755 g. The PCM-temperature controlling system is simple and
has a potential to be implemented as a practical solution to prevent
undesirable heating of the automobile-s cabin.