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    Environmental evaluation of energy efficiency refurbishment in New Zealand's commercial office buildings : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Science in Life Cycle Management at Massey University, Manawatū, New Zealand
    (Massey University, 2017) Ghose, Agneta
    In New Zealand, 80 % of existing commercial office buildings are more than 20 years old and consume approximately 40 % more energy than newer counterparts. Moreover, nearly 38 % of the energy-related emissions in New Zealand’s cities are due to the heating and cooling requirements of commercial office buildings. Therefore, energy efficiency measures in office buildings are recommended to reduce operational energy related costs, provide better working conditions, and enhance business value. An energy efficiency refurbishment which involves adoption of multiple energy saving measures such as thermal insulation, improved glazing, air conditioning and lighting systems, can reduce the energy consumption of existing buildings by nearly 60 %. However, such a refurbishment also involves substantial construction work associated with the demolition and replacement of several building components, and this is associated with additional environmental impacts. It is therefore important to evaluate if the environmental benefits associated with reductions in energy demand can outweigh the environmental impacts of refurbishment. This research investigated the comprehensive environmental impacts of energy efficiency refurbishments in New Zealand’s office buildings using Life Cycle Assessment (LCA). The research used existing data collected for Building Energy End-use Study (BEES) by the Building Research Association of New Zealand (BRANZ). In particular, this research used the information on building design and annual energy consumption of existing and refurbished building prototypes. These building prototypes provided - construction details adopted in buildings of different sizes; and the operational energy performance based on typical climatic conditions found in New Zealand. The environmental performance of the buildings was calculated for Global Warming Potential (GWP), Ozone Depletion Potential (ODP), Photo-chemical Oxidation Potential (PCOP), Acidification Potential (AP), Eutrophication Potential (EP), Abiotic Depletion of resources (ADr), Abiotic Depletion of fossil fuels (ADff), Human toxicity carcinogenic (HT-carc), Human toxicity non-carcinogenic (HT-non carc), Eco-toxicity freshwater (ETfreshwater), Particulate Matter Formation (PMF), and Ionizing Radiation (IR). A series of studies were performed to: (i) assess the environmental impacts and identify the environmental hot-spots of energy efficiency refurbishment, (ii) assess the influence of building’s service life, energy, resource and waste management on the environmental performance of energy efficiency refurbishment, (iii) assess the influence of building size, design and location on the environmental performance of energy efficiency refurbishment, and (iv) to evaluate the contribution of energy efficiency refurbishment to New Zealand’s 2050 climate change mitigation target compared to the environmental performance of existing office building stock. The results showed that at energy efficiency refurbishments can reduce emissions for environmental impact categories affected by energy demand particularly for global warming, acidification and photochemical oxidation. However, the refurbishment is also associated with increase in environmental impacts affected by resource demand such ozone depletion potential, abiotic depletion of resources, human toxicity (carcinogenic) and ionizing radiation. Service life of over 25 years is required to compensate the embodied environmental impacts of refurbishment for most of the impact categories, particularly if the electricity is sourced from renewable energy sources. Refurbished components such as- on-site photovoltaic (PV), aluminium framed windows, façade components and heat pumps were identified as the major environmental hot-spots for most impact categories. The embodied environmental impacts to most categories could be reduced by 20 - 40 % if the waste recovery and recycling at construction site is improved. However, the overall environmental impacts of refurbished office buildings are highly sensitive to the choice of energy supply. Energy supply from grid electricity generated from renewable resources should be prioritised over the use of on- site PV. Benefits from on-site PV is limited if the grid electricity supply is mainly from renewable sources; moreover, the production of photovoltaic panels is energy and resource intensive. It can increase nearly 50 - 100 % of the embodied environmental associated with building refurbishment. If on- site photovoltaic is installed, it should be prioritised in buildings with large roof area located in regions with long sunshine hours. The results also show that in large buildings- efficient heating, ventilation and lighting equipment; and smaller wall to window ratios should be prioritised to reduce environmental impacts. In small buildings, the choice of façade materials with low embodied impacts should be prioritised to reduce environmental impacts. With respect to New Zealand’s 2050 target for the existing office building sector 60 - 90 % greenhouse gas emissions reductions is possible only if the office building stock refurbishment is combined with a renewable energy supply. Nearly 60 – 70 % of the greenhouse gas emissions can be reduced if the refurbishment of the existing office building stock is limited to existing large office building stock (>3500 m2) or to buildings in Auckland and Wellington. The main conclusions based on the results of this research are to prioritise better resource and waste management, to prioritise strategies for maintenance of refurbished buildings to promote longer service life, to support national level policies on increased use of renewable sources for grid electricity generation, and to prioritise refurbishment for a share of the building stock based on size and location which contributes to maximum energy reduction and minimal environmental impacts. The outcomes of this research can support national policy makers and independent building stakeholders (e.g. architects, owners, and engineers) who are keen on promoting energy efficiency refurbishments in New Zealand’s office buildings.
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    A 'pinch' technology analysis of energy integration in the Huntly power station : a thesis presented in partial fulfilment of the requirements for the degree of Master of Technology
    (Massey University, 1990) Tioe, Jen Fuk
    Most processing industries use combinations of heat exchangers for heating and/or cooling process streams. A large amount of the energy used by the processing industries is used just for process heat. In the industrial nations of Western Europe approximately one third of the national energy use is for process heat (Smith, 1981). The design of most industrial processes is based on a long period of development with many evolutions and improvements leading to a current flowsheet. It is often assumed that these flowsheets are more or less optimal, with no significant "faults" left in them. This is of course not true. An analysis carried out by the New Zealand Dairy Research Institute (NZDRI) showed that theoretical minimum energy consumptions are 25 -30% lower than the actual energy consumption of the most efficient of New Zealand's dairy processing plants (Lovell-Smith and Baldwin,1988). For instance, the average energy use per tonne of casein powder produced in New Zealand is 16.9 GJ/tonne but the optimal energy usage is only 9.9 GJ/tonne. Recently, Linnhoff March Limited claimed that 2.5% energy saving in Huntly Power Station is possible but unproven. In terms of money this means about NZ$ 80 million of total saving over the station operating life( ≈ 30 years). [From Introduction]
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    PREM : Personalised residential energy model : a thesis presented in fulfilment of the requirement for the degree Master of Applied Science in Natural Resource Engineering at Massey University, Palmerston North, New Zealand
    (Massey University, 2004) Keller, Reto
    Climate change is a major world environmental problem accepted by these governments who have ratified the Kyoto Protocol which aims to reduce the amount of greenhouse gases (GHG) internationally 5% below the 1990 level during 2008 to 2012. The Protocol needed the ratification of Russia to get into force as the United States and Australia withdrew from the protocol. The New Zealand government ratified the protocol with the negotiated goal to reduce the GHGs back to the level of 1990. The main driver of this study is to help people reducing their personal GHG emissions in order to meet the government's objective of the Kyoto Protocol. Many people know about climate change and understand they will need to change their lifestyle significantly to reduce their GHG emissions. The how and where to change is often unclear. People need to be incentivised in order to encourage emission reduction. Some GHG-calculators already exist, but mostly without practical personalised suggestions and financial effects. This study aimed to develop a model which targeted responses by individuals based on their lifestyle and interests. The Personalised Residential Energy Model (PREM) which was developed in this study uses findings of energy related behaviours from existing psychological and technical research to develop an easy to handle and individualised computer model to assess a person's current energy demand. It includes household and travel demand and assesses the general ecological behaviour. Users will be provided with relevant information to assist them to seek practical and economic solutions in order to reduce their personal CO2 (carbon dioxide) emissions which is the main GHG in the assessed sectors. Starting with the current situation as a baseline, it establishes which behaviours have the highest probability of being undertaken by the person to lower their energy demand. Information about the financial effect and the CO2 emission reductions are provided for specific activities. Energy efficiency and conservation are the main focus of the model output. Further research could include the possible use of renewable energy. Using PREM found changes in domestic dwellings and transportation vehicles to be an important factor in reducing anthropogenic CO2 emissions. The model is made for New Zealand conditions but can be adapted to suit any other country.
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    The renewable energy and energy efficiency potential of Waitakere City : a thesis presented in partial fulfilment of the requirements for the degree of Masters of Technology in Energy Management at Massey University
    (Massey University, 2005) Grooby, Lloyd D
    Electricity restrictions and blackouts have occurred in Waitakere City in the past and are likely to occur again in the future unless the city can become more self reliant by meeting, at least in part, the increasing energy requirements for what is one of the fastest growing cities in New Zealand. In this study the potentials for energy conservation, energy efficiency and renewable energy resources have been broadly quantified and assessed using desktop analysis of publicly available data for stationary final use energy systems (i.e. excluding transportation) within the geographical area of Waitakere City and adjoining waters. It was found that energy efficiency and energy conservation measures can consistently and predictably achieve overall energy savings and reduce daily and seasonal peak demand. The best renewable energy resource potential exists with solar and geothermal for heating applications and wave, offshore and inshore wind and tidal currents for electricity generation. There is very limited potential for hydro and bioenergy systems beyond what already exists. PV solar and land based wind power generation are currently only feasible for limited off-grid applications. This scoping study confirms the achievability of the vision expressed in Waitakere City Council's "Long Term Council Community Plan" (LTCCP) that by 2020 " Waitakere City will be an energy cell, not an energy sink. Air quality supports good health". A range of flagship projects have been identified to progress the achievement of this vision. Waitakere City Council can use this report as part of the development of a comprehensive energy management plan.
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    Selected solar design tools for sustainable residential land development : a thesis presented in fulfilment of the requirements for the degree of Master of Engineering at Massey University
    (Massey University, 2005) Duncan, Andrew
    As New Zealand's natural gas reserves decline and electricity demand growth exceeds the building of new generation plants, greater focus needs to be applied to energy efficient design in domestic buildings and land developments. A case study of residential land development was analysed in terms of its potential for energy efficiency gains and optimisation of solar resources. A design tool was developed to rapidly assess the solar energy loss of a specific building site due to existing land features. 'Solar obstruction contours' were produced that define the maximum permissible height of obstructions before solar shading occurs. These contours were produced based on a minimum percentage solar energy capture. Thermal energy demand for the development case study was calculated by specification of a Building Performance Index relative to floor area. The demand was then balanced against on-site thermal energy production from biomass to give a percentage thermal energy self sufficiency. The tools developed can be used to optimise the design of a residential land development resulting in an increase in renewable energy use above that of standard residential developments. The study concluded that incorporation of the tools as standard practice by municipalities is viable, and if implemented would increase the energy efficiency and renewable energy use of the New Zealand housing stock.
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    Getting the message across evaluating energy efficiency information campaigns in New Zealand : presented in partial fulfilment of the requirements for the degree of Master of Philosophy (Resource and Environmental Planning) at Massey University
    (Massey University, 1995) Heslop, Vivienne Rosemary
    The New Zealand government, state owned enterprises and private organisations have been active, in the past and currently, in promoting energy efficiency and energy conservation through information provision campaigns. However, with a few exceptions, there has been a failure to evaluate the effectiveness of the programmes, and therefore assess whether the programmes have worked. Given the resources that are committed to the development and implementation of these information campaigns, it is important to assess how effective they are. Evaluation of these campaigns can help determine the most appropriate approaches that should be taken in the future, and helps to improve existing campaigns. Evaluation also has an important role to play in terms of accountability within the organisations that operate these information campaigns. A general evaluation process was designed in this research for the evaluation of two selected energy efficiency information campaigns. The evaluation process was designed after thorough reviews of past evaluations of similar campaigns, both in New Zealand and internationally, and from an extensive review of the theoretical and applied literature on programme evaluation. Home energy audit programmes were selected as the energy efficiency information campaigns to be evaluated, with the Energy Efficiency Assessment Plan operated by Southpower, and the Home Energy Rating Options programme being operated by CentralPower being chosen as the two case studies. The results indicate that the programmes evaluated do indeed work; however, analysis suggests that these programmes may be less effective than their potential. From the selected case studies a number of recommendations were developed to improve the effectiveness of the programmes, with a review of the methodology highlighting the limitations of the study. Finally, consideration was given to the role that programme evaluation has in the development, implementation and operation of energy efficiency information campaigns in the future, and its usefulness in assessing the effectiveness of energy efficiency information campaigns in New Zealand.