重庆邮电大学本科毕业设计(论文)
Building management systems and intelligent buildings - environmental and greenhouse gas benefits
Greenhouse gas emission reductions depend on and correlate to reductions in energy use.
Intelligent Buildings and Building Management Systems technologies contribute directly to the reduction in energy use, in commercial, industrial, institutional and domestic residential sectors.
In short, Intelligent Buildings and suitably applied Building Management Systems are good for the environment.
Legislation and environmental standards; health and safety regulations; and global trends towards improving indoor air quality standards are all significant drivers of - and provide a continuous endorsement of the need for - Building Management Systems and the Intelligent Buildings technologies.
Government Initiatives around the world are also driving the development and adoption of Building Management Systems technologies. For example the UK Carbon Trust allows Enhanced Capital Allowance (ECA) to be offset against taxation on energy efficient systems, which enables savings of around 30% for all energy-related Building Management Systems and Intelligent Buildings equipment, and the associated installation and design costs.
Building management systems and intelligent buildings - market trends
Careful interpretation is required. In the UK, adoption of controls technologies into the new build and major refurbishment sectors is relatively high: Estimates a few years ago of the UK market for Building Management Control Systems for new build and major refurbishment, all sectors, suggest market adoption of (as at 1994 - Source UK1 An Appraisal of UK Energy RTD, ETSU -1994): ? Heating controls 70%. ? Hot water system controls 90%. ? Air conditioning controls 80%.
However according to European Commission as many as 90% of all existing buildings have inapplicable or ineffective controls, many of which require complete refurbishment of control systems.
Moreover conventional control systems stop short of automated Intelligent Buildings full capabilities. A significant human element is required for optimal
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重庆邮电大学本科毕业设计(论文)
effective operation even if control systems correctly specified and installed.
Given typical installations and equipment there is often a difficulty for building occupants (residential) or managers (commercial) to operate them correctly. Usage and correct operation are vital for effective results.
Education of users; improved systems-design user-friendliness, and the provision of relevant instructions and information are all critical to enable theory to translate into practice, and for potential effectiveness and savings to be realized. Building management systems and intelligent buildings - practical benefits
Energy-effective systems balance a building's electric light, daylight and mechanical systems for maximum benefit.
Enhanced lighting design is more than an electrical layout. It must consider the needs and schedules of occupants, seasonal and climatic daylight changes, and its impact on the building's mechanical systems. Lighting systems
Adding daylight to a building is one way to achieve an energy-effective design. Natural daylight 'harvesting' can make people happier, healthier, and more productive. And with the reduced need for electric light, a great deal of money can be saved on energy. Nearly every commercial building is a potential energy saving project, where the electric lighting systems can be designed to be dimmed with the availability of daylight. Up to 75% of lighting energy consumption can be saved. In addition, by reducing electric lighting and minimizing solar heat gain, controlled lighting can also reduce a building's air conditioning load. Mechanical systems
The HVAC system and controls, including the distribution system of air into the workspaces, are the mechanical parts of buildings that affect thermal comfort. These systems must work together to provide building comfort. While not usually a part of the aesthetics of a building, they are critical to its operations and occupant satisfaction.
The number one office complaint is that the workplace is too hot. Number two is that it's too cold.
Many people cope by adding fans, space heaters, covering up vents, complaining, conducting 'thermostat wars' with their co-workers, or simply leaving the office. Occupants can be driven to distraction trying to adjust the comfort in their space. Improper temperature, humidity, ventilation, and indoor air quality can
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重庆邮电大学本科毕业设计(论文)
also have significant impacts on productivity and health. When we are thermally comfortable we work better, shop longer, relax, breathe easier, focus our attention better.
In order to provide a comfortable and healthy indoor environment the building mechanical system must:
? Provide an acceptable level of temperature and humidity and safe guard
against odours and indoor air pollutants.
? Create a sense of habitability through air movement, ventilation and slight
temperature variation.
? Allow the occupant to control and modify conditions to suit individual
preferences.
Resistance to building management systems and intelligent buildings technology
? \buildings are already energy-efficient.\(Is the whole building
energy-efficient, or is the landlord limiting his focus to common areas and gross leased spaces?)
? \prefer the equipment with the lowest first cost when fitting out tenant
space.\(Does the specifier have any idea who will bear the increased operating costs of such a strategy?)
? \
the percentage return on money markets is literally one-tenth what it was 20 years ago?)
? \
pay all energy or just the energy over a pre-set base year or expense stop?) ? \selling the building.\(Should we assume then that lowering the
operating expenses and reaping the increased asset value are not important?) Intelligent homes
Building management systems for residential applications
With the widespread adoption of digital technologies there will be a profound change in how we communicate with others. Even how, in our homes, we shop for goods and services, receive news, manage our finances, learn about the world, and, conduct business, manage resources, find entertainment, and maintain independence and autonomy as we enter old age.
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重庆邮电大学本科毕业设计(论文)
These activities increasingly take place in the home. As our perception of banks, shops, universities, communities, and cities change in response to new technologies, so home building management systems are taking on an extraordinary new importance.
As it exists today the home cannot meet these demands or take advantage of new opportunities created by social and technological changes. Most people live in spaces poorly tailored to their needs.
Until recently, the majority of homes were wired with little more than the main electrical circuits, a few phone lines, and a few TV cables. Times have changed. Electrical and security system contractors routinely install low voltage communication network cables for a wide range of intelligent home or 'smart home' systems.
Services and equipment that utilise these networks include: security; home theatre and entertainment; telephones, door-phones and intercoms; PC and internet networks; surveillance cameras; driveway vehicle sensors; communicating thermostats; motorized window blinds and curtains; entry systems; and irrigation systems. Smart homes
'Smart home' is an alternative term for an intelligent residential building, or an intelligent home. A few years ago these concepts wear considered futuristic and fanciful. Now they are reality. These terms are now commonly used to define a residence that uses a control system to integrate the residence's various automation systems.
Integrating the home systems allows them to communicate with one another through the control system, thereby enabling single button and voice control of the various home systems simultaneously, in pre-programmed scenarios or operating modes.
The development of smart home systems focus on how the home and its related technologies, products, and services should evolve to best meet the opportunities and challenges of the future. The possibilities and permutations are endless. Here are some examples: Smart home example scenario 1
A scenario such as 'I'm Home' could be triggered by pressing one button on a
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重庆邮电大学本科毕业设计(论文)
key-ring remote-control from your vehicle as you approach the driveway. The control system receives the key-ring remote-control's command. This will then trigger a pre-programmed sequence of functions. For example starting by turning on the lighting in the driveway, garage, hallway, and kitchen. It then disarms the security system, opens the garage door, unlocks the interior garage entry door, adjusts the heating to a preset temperature, and turns on the whole-house audio system playing your favourite cd, whilst drawing you a bath.
The control system is programmed to meet specific user requirements, initiating sequential automatic operation of the home systems, in response to 'one button' commands based on the situation and or time. Smart home example scenario 2
At 7:30am and you awake to the sound of your favourite cd playing in the background; the lights in your bedroom switch on; 'fading up' to allow you to wake up in your own time. The downstairs intruder alarm system is de-activated. In the kitchen the coffee machine turns on to make a drink. The ground floor curtains and blinds open; the towel heater in the bathroom warms the towels. And you haven't even got up yet.
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