Introduction
The PTM Green Energy Office Building recognised in short :- GEO Building is an administration-cum-research office for Pusat Tenaga Malaysia (Malaysia Energy Centre), following the success of the Low Energy Office (LEO Building) which hosted the Ministry of Energy, Green Technology and Water (KeTTHA) in Putrajaya. The GEO building is a pilot project, a demonstrator building which marked another milestone towards greater promotion and adoption of sustainable building concept in the Malaysian building sector. It is the only such building in Malaysia that integrates the Energy Efficiency, EE and Renewable Energy, RE in one working demonstrator building. The GEO building sited on a 5-acre site in Seksyen 9, Bandar Baru Bangi, Selangor, Malaysia.
The GEO building was designed to be very energy efficient, thus consuming very little fossil fuels with energy index (designed) of 65 kWh/m2year; compared to typical conventional office building in Kuala Lumpur of 250 to 300 kWh/m2year. It was built on a concept which focused on the green technology innovation to minimize energy demand load, efficient use of fossil fuel via taking into account the environmental concern, the usage of renewable energy but without compromising user comfort and safety. Some of the amount of energy used by the building is counter balanced by the amount of energy generated by its own renewable energy power generation system.
Being a pilot project for sustainable office buildings of the future, benchmarked towards 2015, where fossil fuels will have to be used judicially for provision of cooling and lighting features in buildings, the building demonstrates that the GEO concept can be realized using technologies already available today while taking full advantage of an environment where solar generated electricity and daylight are plentiful.
The Building Integrated Photovoltaics, BIPV panels are all integrated into the building design such that it is both architecturally and aesthetically pleasing, as well as providing some of the electricity the building uses. This BIPV system is connected to the national electricity (TNB) grid by feeding electricity into the network and shaving the peak power demand of the grid during the peak daylight hours.
This combination of energy efficient measures together with the renewable energy generation system into the building design can lead to a building with a very low energy consumption, optimizing the usage of the electric grid during cheap off-peak hours, while being aesthetically attractive.
The building integrates Energy Efficiency and Renewable Energy elements early in the design stage. Sophisticated energy simulation software was used intensively during the early design stage which helps in the design process and reducing development cost.
This result in the successful incorporation of advance energy efficient technology which also combined energy generation from renewable source. The already proven Building Integrated Photovoltaic (BIPV) integrated in the building design adds further advantage to the environment since it is non-polluting and abundantly available for free thus reducing the use of fossil fuel.
The super low energy characteristic is achieved by using passive and active energy efficient elements and renewable energy elements as follows:-
The design of the building only allows double glazing windows installed on facade facing north and south. The windows are consists of two pane glass which functioned to filter heat from both infrared and ultraviolet rays from the sun radiation before entering the building interior. This means only cold daylight entered and giving free lighting to the building. This also means that artificial electric light can be turned off during the day hence reducing the energy load of the building. Almost 100 % lighting requirements are from this free source.
Energy efficient T5 tube electrical lighting was installed at the entire building. However, this lighting only be used during dusk, night or during raining because the main source of lighting during the day is provided by the free and filtered natural sun.
The Building Integrated Photovoltaic (BIPV) system provided almost 50% of everyday electrical needs. During the day, the system provides electrical energy which can be exported to the Tenaga Nasional Berhad (TNB) grid when there is surplus of energy. At night, the electrical energy was imported back from the grid to be used for the cooling system.
The building's cooling system is unique because it is a combination of radiant cooling and air convection system. The radiant cooling and ice storage was charge at night and stored at the floor slabs and ice storage tank respectively. During the day, the source of cooling of these sources was distributed by the building's control system to the radiant cooling and air convection system respectively.
In addition to the windows orientation facing north and south only, the building was installed with adequate insulation at the roof and wall particularly facade facing east and west. The building is air tight to avoid internal cold air escapes to the exterior. All this helps to avoid the cooling system works longer hours.
The entire building was controlled with a Building Energy Management System where all building's system operation is controlled automatically. The system also functioned to monitor all energy consumption activities and energy generation in ensuring the building operates efficiently. Energy efficient office equipment was used such as laptops, shared centralized printers, wireless network and energy efficient centralized server.
Other sustainable features integrated are rain water harvest system which helps to conserve water in the building. Rain water is used for air conditioner chiller condenser cooling system, watering the landscape and general cleaning purposes. The average water consumption of the office building is very little compared to conventional office building.
The 21st century is a green century in keeping the earth free from destruction caused by global warming. The GEO building was built to demonstrate that a very energy efficient building can be designed and built today by using current latest green technology with at least cost. With the success of the GEO Building, it may pave the way for such concepts to be applied widely in the building sector.