• Energy Research

Our team looked at the DOD Operational Energy Strategy evolution and how it applies to new and modified weapon systems, considering the three-legged table of the acquisition system: 1) acquisition, 2) requirements and 3) planning, programming, budgeting, and execution (PPBE). We looked at the evolution of the operational energy area initiatives (executive orders, Defense Science Board studies, strategy and policy documents) with a focus on practical ways to gain traction or improve promulgation of key guidance and documentation for new-starts and/or upgrades to weapon system acquisition programs. Additionally, we highlight a few of the in-service initiatives and process improvements underway to reduce fuel consumption. http://archive.org/details/evolutionofopera1094550566 Civilian, Department of the Army Civilian, Department of the Army Civilian, Department of the Army Approved for public release; distribution is unlimited.

The green wall concept has been introduced as one of the solutions to reduce energy demand for ventilation requirements while improving the natural vegetation in dense urban areas. Past studies revealed that the energy-saving of green walls can vary substantially, from 35% to 90% across countries such as United Kingdom (UK), Canada, Russia, Greece, China, Saudi Arabia, India, and Brazil. Given these differences in energy saving of green walls due to climatic conditions and other reasons, direct application of such findings to the Sri Lankan context is questionable. Therefore, this study aimed to assess the thermal performance of green wall applications in Sri Lanka through a case study analysis of an indirect green façade with a comparative conventional wall. The required data were extracted through on-site temperature measurements from different points of both the exterior and interior wall surfaces of each building in different time intervals per day for a period of fourteen days spanning from October to November. The analysis shows that the green walls contribute to 21% - 36% of temperature difference compared to the conventional wall. Eventually, this results in 0.06 kWh of energy-saving per m2 of wall area, and thereby green walls contribute to the 80% energy saving for ventilation requirements. Hence, the study recommends that the use of green walls can be considered as one of the energy efficiency solutions while improving natural vegetation in tropical climatic cities and absorbing other benefits of green walls.

Operational energy consumption in buildings has a crucial impact on global energy consumption. Nevertheless, significant energy savings can be achieved in buildings if properly designed, constructed, and operated. Building Energy Simulation (BES) plays a vital role in the design and optimisation of buildings. BES is used to compare the cost-effectiveness of energy-conservation measures in the design stage and assess various performance optimisation measures during the operational phase. However, there is a significant ‘performance gap’ between the predicted and the actual energy performance of buildings. This gap has reduced the trust and application of the BES. This article focused on investigating BES, reasons that lead to a performance gap between predicted and actual operational energy consumption of buildings, and the ways of minimising the gap. The article employed a comprehensive literature review as the research methodology. Findings revealed that reasons such as limited understanding of the building design, the complexity of the building design, poor commissioning, occupants’ behaviour, etc., influence the energy performance gap. After that, the strategies have been identified to minimise the energy performance gap such as proper commissioning, creating general models to observe occupants’ behaviour in buildings, and using the general models for energy simulation, ensuring better construction and quality through training and education, etc. Further, the findings of this study could be implemented by practitioners in the construction industry to effectively use energy simulation applications in designing energy-efficient and sustainable buildings.

The 2020 Civil Engineering Research in Ireland conference (CERI 2020), Cork Institute of Technology, Cork (held online due to coronavirus outbreak), 27-28 August 2020 In line with the Energy Performance of Buildings Directive, Irish dwellings are being retrofit to near Zero Energy Building (nZEB) standards - with a number of the deep energy retrofits classified as A-rated. As a result of the low operational energy, the embodied energy share of an nZEB's life cycle energy is significantly increased. Therefore, to obtain a holistic picture of the change in energy profile of buildings, the embodied energy of the material added to achieve that low performance should also be taken into account. This paper presents results from a case study of 8 single-occupant terrace bungalows retrofit to nZEB standard. The pre- and post-retrofit operational performance is first estimated using the Irish Dwelling Energy Assessment Procedure (DEAP). The post-retrofit operational performance of the space heating and domestic hot water heating system is also measured over a year. The embodied energy is estimated by way of embodied carbon/energy calculations. Monitored results of the 8 similar buildings exhibit a wide variance of operational energy consumption while the embodied energy is (by nature of the calculation) consistent. The average estimated primary energy requirement for the buildings was 674 kWh/(m2ᐧyear) pre-retrofit and 38 kWh/(m2ᐧyear) post-retrofit while the average measured primary energy requirement for space heating and hot water alone was 119 kWh/(m2ᐧyear) – ranging from 74 to 167 kWh/(m2ᐧyear) for the 8 houses. The embodied energy of the materials and technologies used to retrofit the buildings was 676 kWh/m2. Despite the building performing worse than expected, desirable primary energy and carbon paybacks of 2.0 and 6.1 years were achieved respectively. These positive payback periods are largely due to the very poor operational performance of the buildings pre-retrofit. Sustainable Energy Authority of Ireland 2020-12-15 JG: external PDF cover page removed

The built environment puts the greatest pressure on the natural environment out of all human activities, so it has a fundamental obligation to be environmentally sustainable. Carbon dioxide (CO2) or carbon emissions is a significant greenhouse gas that is inevitably associated with energy use when energy is produced via the combustion of fuels. Total life cycle energy, embodied and operational energy over a building's lifetime, creates significant environmental impacts through the production of CO2. By keeping and reusing existing and historic buildings rather than discarding them and building new, the embodied energy, or the energy that is locked up, can help to mitigate future damage. These buildings already exist, which indicates that the energy consumed to build them has been applied and the carbon associated with their construction has been released. The greenest buildings are ones that are already built. They are inherently more sustainable than any new buildings even with green and zero net energy systems and can be retrofitted to become more energy efficient. To demonstrate this thesis specifically, a design project engages with an abandoned late nineteenth-century bank building in Philadelphia and transforms it into a high-performance building that is prepared for long-term use. For the immediate next use, the project creates a work environment and a new vertical expansion of residential units. The preservation field always confronts the challenge of bridging the gap between embodied energy and operational energy. In the abandoned bank, there are some aspects of this building that are near permanent and define its character, such as brick walls with masonry ornament, two bank vaults, Wissahickon Schist foundation wall, and ceiling trusses. This thesis explores new approaches to leverage the embodied energy of the permanent parts of the abandoned bank and transform it into a high-performance building. A lot of energy of the abandoned bank, the building's material, and thermal mass is still actively performing. The building's envelope, the thick masonry wall, provides a moderately good insulating effect that will temper the indoor air that also preserves its historical character both inside and outside. The embodied energy of the building's envelope is leveraged by pairing it with localized heating and cooling using a radiation and conduction system. Other approaches that increase energy performance in the existing building, include the use of phase-change material for cooling the process water, solar hot water, creating drinking water via a solar still in the skylight, and distilled water from radiant cooling surfaces. In the new construction, a thermal switch facade and double-skin facade for the residential units are proposed, along with providing flexible space with thick mobile interior wall units. Master of Architecture Global warming as a problem of the twenty-first-century increase concentrations of greenhouse gases in the atmosphere due to human actions like burning fossil fuels. The built environment puts the greatest pressure on the natural environment of all industrial parts, and it has a fundamental role to manage the environment sustainably. Total life cycle energy, embodied and operational energy over the lifetime of the buildings, creates significant environmental impacts through the production of CO2. Embodied energy is the whole amount of energy applied to extract the raw materials, manufacture, transport, install, and use the product across its life cycle. Assessments of the embodied energy of historic and existing buildings are helping to mitigate future damage to resources. These buildings already exist, which indicates that the energy consumed to build them has been applied and the carbon associated with their construction has been released. The greenest buildings are ones that are already built. They are inherently sustainable and can be retrofitted to become more energy efficient. Specifically, this design engages with an abandoned late nineteenth-century bank building in Philadelphia and transforms it into a high-performance building that is prepared for long-term use. For the immediate next use, the project creates a work environment and in a new vertical expansion, residential units. In the abandoned bank, there are some aspects of this building that are near-permanent and define its characters, such as brick walls with masonry ornament, two bank vaults, Wissahickon Schist wall, and ceiling trusses. This thesis explores the new approaches to leverage the embodied energy of the permanent parts of the abandoned bank and transform it into a high-performance building. This is achieved through various means such as providing localized heating and cooling by using a radiation and conduction system, the use of phase-change material for cooling the process water, solar hot water, creating drinking water via a solar still in the skylight and distilled water from radiant cooling surfaces. In the new construction, a thermal switch facade and double-skin facade for the residential units are proposed, along with providing flexible space with thick mobile interior wall units.

Abstract With the global energy consumption reaching unsustainable levels, the need for regulating energy consumptions has been emphasised. Hence a variety of methods are followed in different countries to minimise the impacts of embodied energy (EE) and operational energy (OE) in buildings. Considering either EE or OE in its individuality is not a pragmatic approach and it is important to consider means of reducing both EE and OE in parallel. The design stage was identified as the most suitable stage for integrating energy efficiency measures, since most crucial project decisions are taken at this stage. Although a multitude of research has been conducted on EE and OE individually, there seems a lack of research that focuses on both these aspects together. The extensive literature review was followed by 5 preliminary interviews with subject matter experts and then semi structured interviews with 12 experts were conducted. It was revealed that determining strategies for achieving simultaneous EE and OE reduction is difficult. The identified strategies to be implemented in the design stage were classified as material selection related, design approach related, building morphology related, procurement process related and other strategies, with a majority of strategies falling under the ‘procurement process’ category.