Buildings

Explore the Mind Map to learn about the sustainable use of ICT in the Buildings Sector!

In Europe 40% of total energy is used in buildings [1], in China it can be numbered as one third [2]. Because of the high energy demand for heating, cooling, ventilation and lighting in buildings there are many approaches to reduce the energy usage by better insulation and more efficient systems on the one hand, and to make buildings self-supporting in terms of energy supply on the other hand. The potential for energy and emissions savings by improvements in this sector can be considered as large. A recent study in the UK showed that a single domestic property fitted with photovoltaics saved about 1 tonne of CO2 emissions in one year [3]. There are many different options to reduce energy demand in buildings, which refer to directly reducing demand by more efficient systems and insulation, as well as integrating small-scale power generators, which make use of renewable energy sources. To summarize these actions in one term, it is all about improving building design. ICT is the dominating technology to enable such improvements in buildings. Gains in energy efficiency enabled by ICT can mainly be achieved by automation. Therefore systems are developed for automated management and control of lighting, heating, ventilation and air conditioning. To make use of building integrated energy generators, like photovoltaics or wind turbines, ICT systems are needed too. There are already a few projects integrating wind turbines in buildings to provide them with clean and renewable energy [2]. In this context information technology is used to manage the needed electricity grids, that can deal with the varying work load of wind turbines. This implicates the storage of electricity in times when more power is generated than used, as well as managing additional sources of energy when the work load of the wind turbine is too low to meet total demand.
In terms of approaches in reducing emissions, buildings will be closely linked to the power supply sector in future. This is because of the distribution of Smart Grids, that allow buildings to become power supplying units. The are concepts in development, that force electricity generators integrated in buildings as local power stations for electric vehicles [4]. Concepts like these link the buildings sector to the transport sector, mainly to individual transport, as well. This shows the future importance of new approaches in the buildings sector.
The leading term for ICT supported management of buildings is Computer Aided Facility Management (CAFM) [5]. This involves the management, control and maintenance of buildings and its systems. It is the integration of different systems for heating, ventilation, cooling, lighting and small-scale power generators that characterizes the role of ICT in improving building design. An important issue of this integration are open standards, that enable interoperability of different technologies and the usage of new systems in existing buildings [6]. Beside utilization and maintenance of buildings, the advantages of ICT systems can be useful in design, construction and demolition phase too [4]. To reach the whole potential of energy efficiency in buildings, optimization of all phases in a building’s life cycle is necessary. For example there are Building Information Management (BIM) systems [7], that provide architects and engineers with necessary information in design and construction phase, which leads to optimized building design. These systems also enable the automation of design processes, resulting in shorter development times. The advantages of BIM systems can be accounted by energy assessments, improved documentation, air-flow simulations and cost analysis for example. ICT solutions for the use in operational phase of buildings are called Building Management Systems (BMS) [7]. These applications provide functionalities for the automation of monitoring and control of room conditioning and security systems.
The role of ICT for energy savings in buildings as stated by the SMART 2020 Report is as follows [4]:

• Standardize, monitor and account: ICT systems can be used to adapt local heating, ventilation and lighting to the needs of occupants, without wasting resources. Furthermore modeling and simulating energy usage scenarios in buildings and benchmarking of building performance is enabled. The establishment of standards for technology compatibility and benchmark comparison would ease efficiency gains. Improvements in building design can be achieved by networks for remote monitoring and management of building systems and automation solutions, based on energy efficient hardware. 
• Rethink: The inefficiencies of building management systems can be found and improved by the use of ICT. Also the involvement and engagement of users has to be extended to reach an optimum in energy usage. Information plays a major role in this adoption process towards a low carbon economy. 
• Transform: The vision of future building design involves buildings which are adjustable to user preferences. Therefore improved user interfaces are needed. To make building usage more efficient technologies for teleworking and collaboration have to be improved. Future buildings should be equipped with local energy supply (e.g. photovoltaics) and systems for automated control, diagnosis and maintenance. 

There are estimations that the total emissions arising from building sector will reach 11.7 GtCO2e in 2020. The Smart 2020 Report states that improved building design and the use of automation technology could save 1.68 GtCO2e globally [4]. Other sources expect that the building sector would be able to reduce its greenhouse gas emissions by 30-35 percent by 2050, in spite of growing numbers of buildings, by tapping the full potential of today’s technology [7]. Basically there are two types of improving building design. The first possibility is to equip new buildings with modern building management systems in construction phase. The systems are already considered in design phase, which makes optimization easier in comparison to integrating such systems in existing building, which is the second type of improvement. To reach the amount of emissions saving that is needed to successfully address the climate problem, both types of improved building design have to be realized. Equipping existing buildings with modern technologies globally is a large-scale project, but the energy saving potential is large. The retrofitting of existing buildings is a major part of the possibility supplied by ICT to reduce the carbon footprint of the building sector [6], since 80 percent of the existing building stock is more than 10 years old [7].
Complying to the three dimensions of sustainability the net benefit of ICT enabled improved building design has economic, environmental and social aspects [7]:

• Economic benefit – Reduced operating costs of facilities, due to lower energy consumption in design, utilization and maintenance. – Investments in the economy, in form of retrofitting activities and development of innovative building design to meet new standards and requirements. 
• Environmental benefit – An estimation of 33.5 million tons of CO2 savings per year. 
• Social benefit – Creation of jobs in design and construction of buildings for retrofitting and design improvements. 

Although large energy savings can be expected from improvements in building design, commissioning, utilization, operation and maintenance, there are some hurdles to adopt these technologies. There is a lack of incentives for building designers and architects to integrate energy saving technology into buildings, since the payback periods are often long [4]. Therefore it is up to governments to provide such incentives, for example by tax deductions for reaching certified performance levels of energy efficiency in buildings [7]. The need to measure efficiency levels of buildings is one part of the importance of establishing standards for building technologies. There have to be standards in rating systems and valuation tools for buildings [4], as well as standards for the interoperability of building integrated technologies. Standardization is one of the benefits ICT can offer to other sectors. It is one of the reasons for the success of the ICT sector, that it established international standards for communication and information exchange [6]. The success of reducing energy demand and emissions in the building sector will depend on the agreement on standards for system design and monitoring. Standards can be seen as a basis for achieving potential efficiency gains [6], because of their characteristic to offer interoperability and comparability.

References

[1] W. Zeiler, R. Houten, G.t Boxem, P. Savanovic, J. Velden, W. Wortel, J.-F. Haan, R. Kamphuis, and H. Broekhuizen. Design ontology for comfort systems and energy infrastructures: Flexergy.  In Robert J. Howlett, Lakhmi C. Jain, and Shaun H. Lee, editors, Sustainability in Energy and Buildings, pages 49–58. Springer Berlin Heidelberg, 2009.

[2] B. Cai and H. Jin.  Development and strategies of building integrated wind turbines in china. In Robert J. Howlett, Lakhmi C. Jain, and Shaun H. Lee, editors, Sustainability in Energy and Buildings, pages 71–78. Springer Berlin Heidelberg, 2009.

[3] F. J. O’Flaherty, J. A. Pinder, and C. Jackson. The role of photovoltaics in reducing carbon emissions in domestic properties. In Robert J. Howlett, Lakhmi C. Jain, and Shaun H. Lee, editors, Sustainability in Energy and Buildings, pages 107–115. Springer Berlin Heidelberg, 2009.

[4] The Climate Group. Smart 2020: Enabling the low carbon economy in the information age. Technical report, The Climate Group on behalf of the Global e-Sustainability Initiative (GeSI), 2008.

[5] International Facility Management Association (IFMA). Glossary of facility management
terms. http://fmpedia.org/. Accessed: 2011-11-07.

[6] B. Tomlinson. Greening through IT - Information Technology for Environmental Sustainability. The MIT Press, 2010.

[7] G. Philipson. Ict’s role in the low carbon economy. Technical report, Australian Information Industry Association (AIIA), 2010.

Intelligent Building Systems - Lighting Automation - HVAC Automation

Intelligent Building Systems

The term Intelligent Building System refers to the integration of various building facilities by computer systems. Such a system provides a centralized control application for example for HVAC (heat, ventilation and air conditioning), security systems, lighting systems, energy management, access control and telecommunications [1]. In other words, Intelligent Building Systems try to integrate several building automation systems. As mentioned before, these systems are developed to control innovative technologies to increase energy efficiency as well as user benefits. Approaches of this kind address the fundamental issue of achieving reductions in energy demand in buildings without lowering the quality of in-building conditions for occupants. This is of special importance for the distribution of energy efficient technology, since it can also bring direct benefits for users, beside the positive environmental impact. To reduce energy consumption in buildings Intelligent Software Agents (ISA) can be installed at different levels of automation. The focus of this approach is set on individual climate control to adjust the conditions to user preferences by an optimal setting of parameters. This implies profound knowledge of the actual weather situation and data about the building like window orientations. An approach of this kind was tested in field in office buildings in the Netherlands [2]. Although this technology is still in research phase, it is a promising concept to deal with the trade-off between energy savings and individual comfort.

Lighting automation 

Lighting is responsible for about 20 percent of total energy demand in commercial buildings and for about 10 percent of energy demand in residential homes [3]. One possibility to reduce this energy consumption is to use more efficient illuminants, like light-emitting diodes (LED). On the other hand the inefficiencies in lighting of today’s buildings arise from light usage. Light should be turned on when it’s needed and should be turned off when it’s not necessarily needed. This approach can be named as occupancy-based lighting [4]. At this point automated lighting systems come to play. Modern lighting control systems are computer systems that allow automated control and optimization of lighting in office or private buildings, that maximize efficiency and therefore save energy. The energy savings from these control systems can be numbered as up to 70 percent of today’s energy demand for lighting [5]. The global potential of emissions savings by lighting automation is estimated by about 0.12 GtCO2e [4], which would bring a significant environmental benefit. Additionally there are important social and economic benefits, like improved and individually adjusted room lighting and lower operational costs due to lower energy consumption.
Typical features of modern lighting control systems are the following [5, 6]:

• Direct on/off and dimming controls provided to the occupants at a centralized control user interface. 
• Possibility of remote management of lighting control of all individual lights in a whole building or several buildings combined. 
• Scheduling functions and timers, switching lights on and off or dimming lights automatically at predefined times. 
• Integration of photo-sensors to detect illumination levels of natural lighting. This allows to adjust additional artificial lighting efficiently to meet the required illumination levels and save a significant amount of energy. 
• Occupancy sensors, to enable occupancy-based lighting, especially useful in areas with varying usage. 
• Functions for measuring and monitoring energy consumption of lighting, which provide real-time or historical data on energy usage for decision making. 

As already mentioned lighting control systems can not only provide energy savings, they can also bring advancements in lighting characteristics like illumination levels in respect to the requirements at different places. As an example, lighting can be individually adjusted to several specific workplaces in the same room. Beside environmental benefits, this induces significant economic and social improvements, since it is the sense of artificial lighting to improve the productivity and wellbeing of a buildings occupants. To achieve individuality in lighting and to adjust it to user preferences, a flexible structure of the lighting network is needed. This involves a multiple-circuits configuration with local and remote control functions and individually positioned luminaries at specific areas per room [7]. Approaches like this focus at ensuring that savings in energy are not achieved at the cost of performance. However a simple case study at a small office showed, that automated lighting control could lower energy usage to about 30 or 40 percent of energy usage without any lighting control facilities [7].
One problem for adoption of lighting control systems in existing buildings are the high costs of installation and rewiring [8]. Wireless technology could help overcome this hurdle, since it is better compatible with economic considerations due to lower investment expenses for retrofitting. In the case of wireless lighting control a network of wireless photo- and occupancy sensors, as well as wireless light switches and dimmers is installed, which means that “each endpoint is wirelessly enabled” [5]. Figure 1 shows a schema of a simple wireless lighting architecture, using wireless actuation modules for luminaries with dimming functions and a base server for lighting control. The system is designed as wireless networked intelligent lighting actuation system, to gain energy savings and satisfy the needs of individual occupants [8].

Figure 1: Wireless networked lighting architecture [8]

More complex wireless lighting networks use mesh-architectures, meaning that every endpoint can communicate with the controller by at least two channels, which makes the network more stable and more resistant to failures due to redundancy [5]. Beside the relatively low costs of retrofits, the major benefits of wireless lighting control are flexibility in placing lighting controls and reconfigurations of the network, as well as high scalability in respect of adding devices and expanding the network.

Heat, ventilation and air conditioning (HVAC) automation 

Similar to lighting control, heating, ventilation and air conditioning can also be automated by special building automation system (BAS). In this case the BAS is a computer network integrating the controls of heating, ventilation and air conditioning systems of buildings, which also can be automated [6]. A main goal of these systems is to adjust HVAC settings to occupants needs in order to save energy and improve room conditions. In China HVAC systems are responsible for more than 70 percent of total energy use in buildings [9]. Globally the automation of HVAC systems could save up to 0.13 GtCO2e [4].
The full potential of energy savings from improving HVAC systems in the building sector can be tapped by developing hybrid systems for heating and cooling that use efficient and low carbon energy sources. An example of a hybrid air conditioning system is a combination of a vapor-compression system, a desiccant dehumidification system and a indirect evaporative cooling system [9]. To achieve maximum efficiency of such combined systems information technology is needed to optimize and operate them. For proper and efficient building ventilation there are hybrid concepts too. These systems use a combination of natural ventilation and air conditioning [10].
Another approach of reducing energy demand for heating and cooling is to exploit geothermal energy. This brings significant environmental benefits, since this type of energy is carbonfree and widely available. The main principle of these systems is the heat pump, which works like a “reverse refrigerator” [11]. The ground heat is used for building heating in winter, since the soil is warm relatively to the air on the surface. In summer the soil can be used to cool the building by reversing this principle. Figure 2 depicts a simple schema of a heat pump system.

Figure 2: Ground source heat pump system for building heating and cooling [11]

Geothermal systems are often used in context of passive building concepts with a low grade of natural ventilation. These concepts often optimize energy consumption at the cost of room conditions. To improve room conditions, additional active ventilation systems are necessary, to achieve the required level of air exchange in these buildings. In contrast to this, there are approaches in research to use geothermal energy with the help of ground air collectors to realize active conditioning systems. The advantage of this method is, that the whole building construction is warmed by naturally preheated air in winter and cooled by natural cool air in summer [12]. The principle is similar to traditional heat pumps, but the main difference is that air is used to heat or cool the building instead of water. By collecting ground air a higher level of ventilation can be achieved to improve room conditions and the need for additional ventilation can be avoided.
Heating of buildings by traditional systems using fossil fuels has large environmental impact. In the UK tempering buildings accounts for about 49 percent of total carbon emissions [13]. There are several technology approaches for low carbon domestic and nondomestic heating, to lower this environmental impact. Such heating systems are called microgeneration heat technology, since they are built in small-scale factor and mainly used to heat single building units [13]. Some samples for microgeneration heat technology used for room and water heating are heat pumps, solar thermal hot water, biomass stoves and boilers fuelled by wood or pellets. Just as for other building technologies the role of ICT is to control these microgeneration heat systems, integrate them with other building automation systems and therefore optimize the efficiency.
A study from the UK about the use and adoption of low carbon microgeneration technology addressed the reasons for or against the adoption of these technologies [13]. The survey showed that a big part of the adopters of microgeneration heat technologies considered themselves as “environmentally conscious” and took also different actions to reduce their energy demand, like using public transport for example. Households in rural areas, with no children, or where children already left home, are more likely to adopt low carbon technology as well. The main reason for adoption is the idea to lower bills and carbon emissions. On the other hand, the largest barriers for adoption are mainly financial: high initial costs, uncertain and long payback periods, small subsidies [13]. In summary there are financial, regional and ideological factors that influence the decision for or against adopting new technology to lower the environmental impact of domestic heating systems. The uncertainty about payback periods and efficiency of these systems that prevents many households from adoption. Therefore a well-directed information campaign and higher incentives given by governments could help overcome these barriers and support a faster distribution of low carbon heating technologies.

References

[1] Diamond Electronic Systems Ltd. http://www.diamondsystems.co.uk/index.php?option=com_content&view=article&id=81&Itemid=84. Accessed: 2013-03-08.

[2] W. Zeiler, R. Houten, and G. Boxem.  Smart buildings:  Intelligent software agents.  In
Robert J. Howlett, Lakhmi C. Jain, and Shaun H. Lee, editors, Sustainability in Energy
and Buildings, pages 9–17. Springer Berlin Heidelberg, 2009.

[3] B. Metz. Controlling climate change. Cambridge University Press, 2010.

[4] The Climate Group. Smart 2020: Enabling the low carbon economy in the information age. Technical report, The Climate Group on behalf of the Global e-Sustainability Initiative (GeSI), 2008.

[5] Daintree  Networks,   Inc.      White  paper:    The  value  of  wireless  lighting  control.
http://www.daintree.net/downloads/whitepapers/smart-lighting.pdf.  Accessed: 2013-03-08.

[6] R. Wolsey.  Controlling lighting with building automation systems.  Lighting Answers, Vol. 4 Number 1:1 – 8, May 1997.

[7] G. Parise and L. Martirano.  Impact of building automation, controls and building management on energy performance of lighting systems.  In Industrial Commercial Power Systems Technical Conference - Conference Record 2009 IEEE, pages 1 –5, May 2009.

[8] Y.-J. Wen and A.M. Agogino. Wireless networked lighting systems for optimizing energy savings and user satisfaction. In Wireless Hive Networks Conference, 2008. WHNC 2008. IEEE, pages 1 –7, Aug. 2008.

[9] K. Sumathy, Li Yong, Y. J. Dai, and R. Z. Wang.   Study on a novel hybrid desiccant dehumidification and air conditioning system. In Robert J. Howlett, Lakhmi C. Jain, and Shaun H. Lee, editors, Sustainability in Energy and Buildings, pages 413–421. Springer Berlin Heidelberg, 2009.

[10] A. Elmualim. Integrated building management systems for sustainable technologies: Design aspiration and operational shortcoming. In Robert J. Howlett, Lakhmi C. Jain, and Shaun H. Lee, editors, Sustainability in Energy and Buildings, pages 275–280. Springer Berlin Heidelberg, 2009.

[11] B. Metz. Controlling climate change. Cambridge University Press, 2010.

[12] W. Zeiler and G. Boxem. Geothermal active building concept. In Robert J. Howlett, Lakhmi C. Jain, and Shaun H. Lee, editors, Sustainability in Energy and Buildings, pages 305–314. Springer Berlin Heidelberg, 2009.

[13] S. Caird and R. Roy. Adoption and use of household microgeneration heat technologies. Low Carbon Economy, 1(2):61–70, December 2010.

Dematerialization by Telework and Videoconferencing

Telework

In nearly every economic sector ICT can be used for the dematerialization of physical products or processes. Teleworking has an effect on the transport sector, since the travel ways to and from offices can be reduced by working from home. The Telework Research Network published following figures about the saving potential induced by teleworking in the United States of America [1]:

• Savings of over 280 million barrels of oil. 
• Greenhouse gas savings of 53 million tons, which would be over 21 percent of the USA’s aim of reductions by 2020. 
• Savings of about 1 billion dollar in highway maintenance, due to reductions of wear. 
• Companies could save 200 billion dollar in office buildings, including utilization and maintenance costs. 
• The resulting electricity savings from offices could power 900,000 homes per year. 
• Reductions in traffic related injuries and deaths, resulting in cost savings of 12 billion dollar a year. 
• Each employee could save up to between 1,800 and 6,800 dollar in transportation and work-related costs. 
• While 40 percent of employees in the USA have jobs that would allow teleworking, only 2 percent work from home most of the time. 

In total the extensive use of telecommuting could save more than 650 Billion Dollar a year. According to the authors of the referenced website, these figures are a result of synthesizing 250 case studies, a number of reviews and interviews with virtual employers and their employees, as well as top researchers on the topic [1].

Also The Climate Group states in it’s SMART 2020 Report that more than half of the emissions saving potential of dematerialization by ICT is made up of the proliferation of telecommuting. In numbers this would be 0.26 GtCO2e in 2020 globally [2]. Other researchers assume the potential savings in greenhouse gas emissions due to telecommuting to be 588.2 million tons just for the USA [3]. One of the major environmental benefits of telecommuting arises from reduced work-related travel. Due to the possibility for people to increasingly work from home, this “could provide help in de-coupling transport growth and economic growth” [4]. The reduction in physical traffic volume may be partly offset by additional trips in leisure time. Furthermore telecommuting could be a reason to move to rural areas, which would result in longer distance travel at days when working at the office [3]. These coherences can be termed as rebound effects. Studies approved that in some cases teleworkers undertake additional trips, that would usually be combined with traveling to and from workplace (e.g. shopping), which offset about half of the travel savings in average [4]. Taking all the considerations into account, an increase of telecommuting would have a significant positive effect on the environment.

Telework is also a concept of dematerialization in the buildings sector. Studies show that a significant number of workers working from home at three days a week could lead to energy savings of 20 to 50 percent, even when the resulting increase of energy demand in homes is considered [2]. Telecommuting or telework was enabled by the distribution of broadband networks, that allow to transfer large amounts of data. It means “working remotely via the use of ICT solutions” [2], while the remote workplace is usually represented by the private home. The energy and emissions savings are composed of reduced travel routes and the possibility for companies to build and maintain smaller offices. This requires the sharing of workplaces, which makes at least three days of teleworking a week necessary. The space in typical office buildings is utilized only about 18 percent of total time [5]. This fact shows that the improvement of utilization of existing space, could lead to reduced demand for new buildings and therefore to a significant reduction of emissions, arising from construction, utilization and maintenance of new buildings. A precondition to energy and emissions savings by telecommuting in the buildings sector is, that teleworkers give up their office spaces, or at least share them. Otherwise reductions in carbon emissions by telecommuting can be expected from reduced travel only [4]. A research work done in the USA is assuming that a home office would bring energy savings of about 3500 kWh on average compared to a commercial office. This would lead to savings of 46.6 billion kWh of electricity, or 56.8 tons of CO2e per year, at a supposed number of 13.3 million telecommuters in the USA [3].

Videoconferencing

A second example for the dematerialization of travel ways is videoconferencing. This approach replaces physical meetings by providing ICT equipment for video-telephony over the Internet. There are studies that claim that significant reductions in emissions could be achieved by reducing physical traffic by videoconferencing [6]. In this context it has to be mentioned, that approaches like videoconferencing and telecommuting have already been existing for a while and have not been adopted as widely as it could have been expected during this period [2]. In 2005 only 3,9 percent of the population of the 25 member states of the European Union regularly used the Internet for video- or audio conferencing [4]. This shows that the level of acceptance is an important issue for the adoption of ICT developments. Therefore it is essential that the ICT infrastructure allows an adequate user experience while videoconferencing for example, so that it gets a viable alternative to physical meetings [6].

A research work of 2004 from Norway on the impact of videoconferencing on business travel determined, that the substitution rate of business air travel by videoconferencing is only 2.5 to 3.5 percent [7]. The author also claimed, that videoconferencing is mainly used for intracompany communication. This fact suggests that personal contact is still the preferred way of conducting business between companies and maybe will remain dominant over virtual meetings. The main reasons for companies for the adoption of videoconferencing are time and cost savings (cf. figure 1) [7]. It can be hypothesized that a significant increase in travel costs could be a reason for companies to utilize videoconferencing technology more extensive. Several case studies showed that the potential carbon savings arising from the use of teleconferencing (audio and video), can be numbered as about 15 percent of the company’s business travel [4].

Figure 1: Reasons for videoconferencing (a higher score means more important) [7]

References

[1] teleworkresearchnetwork.com. Telework savings potential. http://www.teleworkresearchnetwork.com/cut-oil. Accessed: 2013-02-12.

[2] The Climate Group. Smart 2020: Enabling the low carbon economy in the information age. Technical report, The Climate Group on behalf of the Global e-Sustainability Initiative (GeSI), 2008.

[3] J.P. Fuhr and S. Pociask. Broadband and Telecommuting: Helping the U.S. Environment and the Economy. Low Carbon Economy, vol.2:41–47, 2011. 

[4] Bio Intelligence Service. Impacts of information and communication technologies on energy efficiency, final  report. ftp://ftp.cordis.europa.eu/pub/fp7/ict/docs/sustainable-growth/ict4ee-final-report_en.pdf, September 2008. Accessed: 2013-02-12.

[5] B. Tomlinson. Greening through IT - Information Technology for Environmental Sustainability. The MIT Press, 2010.

[6] P. Fernando and A. Okuda. Escap technical paper: Green ICT - a “cool” factor in the wake of multiple meltdowns. http://www.unescap.org/idd/working%20papers/IDD_TP_09_10_of_WP_7_2_907.pdf, December 2009. Accessed: 2013-02-12. 

[7] J.M. Denstadli. Impacts of videoconferencing on business travel: the norwegian experience. Journal of Air Transport Management, 10(6):371 – 376, 2004.