Design and assessment of an energy efficient office building utilising a building management system. A study of a use case in Cape Town.

Date
2017-03
Journal Title
Journal ISSN
Volume Title
Publisher
Stellenbosch : Stellenbosch University
Abstract
ENGLISH ABSTRACT: According to the WWF, food, water and energy security form the basis of any selfsufficient economy. A crisis in any of the three systems will directly affect the other two. The WWF believes that effectively averting such a crisis requires enhanced information, coordinated planning and adapting to a resource-scarce future. As a result of a global movement toward “green” or sustainable living and possibly boosted by the recently experienced crises in two of these systems, businesses in South Africa have adapted by investing in “green” or resource efficient facilities. The Green Building Council of South Africa, through their rating system, provides a certification process to acknowledge market leaders in this movement. With the development of modern buildings, electronic building systems and controls become increasingly complex, necessitating the use of a building management system. The V&A Waterfront’s No. 5 Silo building in Cape Town is no different. It is one of a number of buildings in the Silo district that makes use of a seawater district cooling system as an alternative source, primarily for air conditioning purposes. It also utilises a central air conditioning system that incorporates a number of energy saving features. All of its air conditioning systems are also monitored and controlled by a building management system. This research focusses on the design and assessment of an energy efficient office building, concentrating specifically on the role that a building management system plays in achieving energy efficiency. Various methods of reducing resource consumption or improving system efficiencies are investigated and discussed based on implementation, achievable savings, costs and other complexities. Focus areas include the use of alternative, more sustainable sources, various optimisation methods as well as closely monitoring and reporting of consumption data. The impact of a building management system and the green building rating system on a building project and specifically on its resource efficiency is also evaluated. This information gathered from existing literature is used to assess savings methods that are applied to the No. 5 Silo building. The design, construction and operation of its air conditioning systems are described in depth, focussing on energy saving practices and ways of quantifying the potential savings. The No. 5 Silo building management system is practically tested for its functionality and is used to gather operational data from the building to investigate potential energy savings. The data is processed, presented graphically and interpreted in terms of its usefulness, visible savings and other trends or events that are identified. The results confirm that substantial savings are achieved through the use of the district cooling system. It also quantifies and proves the previously unknown amount of energy saved through the economy cycle feature of central air handling units. The combined effect of the results and preceding tests also proves the building management system to be an invaluable tool for the monitoring and controlling of building systems from a central point. Transferability to other scenarios (buildings, regions) will be evaluated, and key lessons learned will be captured for the benefit of future ventures.
AFRIKAANSE OPSOMMING: Volgens die WWF word voedsel, water en energie sekuriteit geïdentifiseer as die fondasie van enige selfonderhoudende ekonomie. In die geval van ‘n ernstige tekort in die verskaffing van enige een van die drie hulpbronne, sal dit ‘n direkte uitwerking op die ander hulpbronne hê. Die WWF beweer dat verbeterde inligting, gekoördineerde beplanning en aanpassing tot ‘n toekoms met geringe hulpbronne noodsaaklik is om so ‘n ramp te voorkom. As gevolg van die huidige beweging in die rigting van ‘n meer “groen” of volhoubare lewenstyl asook die onlangse ernstige tekort in die beskikbaarheid van twee van die bogenoemde hulpbronne, begin Suid-Afrikaanse besighede aanpas deur te belê in “groen” geboue asook geboue waar hulpbronne op doeltreffende maniere ingespan word. Die Green Building Council of South Africa bied, deur hulle graderingstelsel, ‘n sertifiseringsproses wat daarop ingestel is om erkenning te gee aan voorlopers in die “groen” beweging. Met die ontwikkeling van moderne geboue word elektroniese gebou sisteme en beheerstelsels al meer kompleks en gevolglik het die gebruik van gebou beheerstelsels noodsaaklik geraak. Die V&A Waterfront se No. 5 Silo gebou ervaar dieselfde tendens. Dit is een van ‘n paar geboue in die Silo kompleks wat gebruik maak van ‘n seewater distrik verkoeling stelsel as ‘n alternatiewe hulpbron gebruik, hoofsaaklik vir lugversorging doeleindes. Die gebou benut ook ‘n sentrale lugversorging stelsel wat verskeie funksies gebruik om energie te bespaar. Alle lugversorging stelsels word ook gemonitor en beheer deur ‘n gebou beheerstelsel. Hierdie navorsing fokus op die ontwerp en analisering van ‘n energie doeltreffende kantoor gebou. Aandag word spesifiek gerig op die rol wat ‘n gebou beheerstelsel speel in die energie doeltreffendheid van so ‘n gebou. Verskeie metodes word ondersoek en bespreek rakende die vermindering van die gebruik van hulpbronne asook die verbetering van die doeltreffendheid van sisteme. Die evaluasie word baseer op implimentering, moontlike besparings, kostes en ander faktore. Die metodes word gekategoriseer onder drie area naamlik, die gebruik van alternatiewe, volhoubare hulpbronne, optimering van sisteme asook die monitor en rapportering van die gebruik van hulpbronne. Die impak van ‘n gebou beheerstelsel asook die groen gebou graderingstelsel op ‘n gebou en meer spesifiek op die effektiewe gebruik van hulpbronne in die gebou, sal ook deeglik ondersoek word in die navorsing. Bestaande literatuur word verder gebruik om metodes wat op die No. 5 Silo gebou toegepas is te evalueer. Die ontwerp, konstruksie en werking van die gebou se lug versorging stelsels word in diepte verduidelik met betrekking tot energie besparings tegnieke en metodes om moontlike besparings te kwantifiseer. Die gebou beheerstelsel van die NO. 5 Silo gebou word breedvoerig getoets om die funksionaliteit daarvan te beproef asook om operasionele data in te samel wat verder gebruik word om moontlike energie besparings te ondersoek. Data word verwerk, visueel voorgestel asook geïnterpreteer ten opsigte van gebruikswaarde en sigbare besparings. Ander tendense en spesifieke gebeurtenisse word ook geïdentifiseer en bespreek. Die uitslae van die navorsing bevestig dat aansienlike besparings behaal word deur die gebruik van distrik verkoeling stelsel. Dit bevestig en kwantifiseer ook die voorheen onbekende hoeveelheid energie wat bespaar word deur die “economy cycle” kenmerk van sentrale lugversorging eenhede. Die oorhoofse effek van die uitslae en die voorafgaande toetse bevestig gebou beheerstelsels as ‘n as ‘n uiters waardevolle hulpmiddel vir die monitor en beheer van gebou stelsels vanaf ‘n sentrale punt. Die oordraagbaarheid na ander scenario’s (verskillende geboue en omgewings) sal geëvalueer word en waardevolle ondervindings sal bespreek word ter voordeel van toekomstige ondernemings.
Description
Thesis (MScEng)--Stellenbosch University, 2017.
Keywords
Buildings -- Management, UCTD, Energy consumption, Fuel efficiency, Office buildings, Seawater -- Cooling systems
Citation