Zero Energy Buildings (ZEB) use innovative design and technology to reinvent how they manage their power usage.
ZEB use roughly the same amount of energy that they generate annually.
The Zero net building principle relies on action taken to reduce reliance on fossil fuel therefore reducing carbon emissions.
In order to do so building features create alternative means of energy or introduce energy reducing schemes.
Pasona HQ, Japan
Pasona HQ is a nine story high, 19,974 square metre corporate office building for the Japanese recruitment company located in downtown Tokyo.
It is a major renovation project consisting of a double-skin green facade, offices, an auditorium, cafeterias, a rooftop garden and most notably, urban farming facilities integrated within the building.
The green space totals over 43,000 square feet with 200 species including fruits, vegetables and rice that are harvested, prepared and served at the cafeterias within the building.
Japan produces less than 1/3 of their grain locally and imports over 50 million tons of food annually, which on average is transported over 14,500 kilometres, the highest in the world.
As the crops harvested in Pasona HQ are served within the building cafeterias, it highlights ‘zero food mileage’ concept of a more sustainable food distribution system that reduces energy and transportation cost.
Using both hydroponic and soil based farming, crops and office workers share a common space.
Tomato vines are suspended above conference tables, lemon and passion fruit trees are used as partitions for meeting spaces, salad leaves are grown inside seminar rooms and bean sprouts are grown under benches. The main lobby also features a rice paddy and a broccoli field.
These crops are equipped with metal halide, HEFL, fluorescent and LED lamps and an automatic irrigation system.
An intelligent climate control system monitors humidity, temperature and breeze to balance human comfort during office hours and optimise crop growth during after hours.
Plants are also known to improve the air quality we breathe by carbon sequestration and removing volatile organic compound. A sampling on the air at Pasona HQ have shown reduction of carbon dioxide where plants are abundant.
Such improvement on the air quality can increase productivity at work by 12%, improves common symptoms of discomfort and ailments at work by 23 per cent, reduce absenteeism and staff turnover cost.
Pearl River Tower, China
Pearl River Tower in China is a 213,700 square metre office building that directs wind to a pair of openings at its mechanical floors, where traveling winds push turbines that generate energy for the entire building.
Architecture, interior design, engineering, and urban planning firm, SOM incorporated the latest sustainable technology and engineering know-how into its design of this 309-meter-tall.
The building also has solar panels, a double-skin curtain wall, a chilled ceiling system, under-floor ventilation, and daylight harvesting, all of which contribute to the building’s energy efficiencies.
Triple-glazed facades with exterior blinds are located on the east and west elevations, and internally ventilated double-skin facades are located on the north and south.
Both north and south facing facades feature automated blinds which contribute greatly to the building’s energy efficiency.
LPL Financial HQ, San Diego
LPL Financial’s San Diego headquarters is the largest Zero energy commercial office building in the United States.
The 13 storey, 38,555 square meter office tower includes three fuel cells to convert biogas into carbon-neutral electricity that will allow the building to achieve net-zero energy status.
In order to monitor and manage the tower’s reduced energy consumption, energy meters are located throughout the building and all surplus power is pushed back to the grid through San Diego Gas & Electric.
In addition, the tower is furnished with LED lights that feature automatic dimming capabilities based on the degree of available natural light, as well as occupancy sensors that turn lights off by detecting unoccupied offices.
88 per cent of the tower’s water consumption, nearly 2.5 million gallons annually, is recycled and used for irrigation and other building needs.
Employee-focused sustainability programs encourage employees to recycle, compost and carpool.
On-site charging stations for electric vehicles are also available for employee use at no cost.
Bullitt Centre, Seattle
The Bullitt Center, a six-storey, 15,240 square metre office building in Seattle, aspires to be the world’s greenest commercial building operating 83 per cent more efficient than a typical commercial site in Seattle.
This $30 million “living laboratory,” designed by Miller Hull Partnership, distinguishes itself from other sustainable projects with its composting toilets, the exclusion of 350 common toxic chemicals – including PVC, lead, mercury, phthalates, BPA and formaldehyde – along with a strict energy and water budget that aims for self-sufficiency under the Living Building Challenge.
The energy saving features include a rainwater collection system into a 211,983 litre cistern where the water is then filtered and disinfected. Another is ten bright blue aerobic composters, each about the size of a Fiat 500, composting human waste so odourlessly and efficiently that the first compost extraction will not be required for 18 months. A third is the building’s rooftop array of photovoltaic panels, which extend far behind the building’s edge to produce around 230,000 kilowatt hours a year.
The mechanical and electrical rooms of the Bullitt Center will have large glass windows that display the state-of-the-art engineering, where tourists can scan quick response codes with a smartphone to learn about individual elements.
A kiosk displays real-time measurements of the building’s indoor air quality, energy consumption, photovoltaic power production and water levels.
The building will be so closely monitored that managers will be able to track down energy consumption to an individual plug.
Four metre high ceilings and 3 metre windows on the upper floors contribute to an airy loft like feel and maximize on daylight and a glass-enclosed stairwell is a smart way to encourage visitors and inhabitants to move while also conserving energy.
BCA Academy, Singapore
The Building and Construction Authority (BCA) completed Singapore’s first retrofitted Zero Energy Building (ZEB) located at the BCA Academy.
ZEB officially opened on 26 October 2009 by Minister for National Development, Mr Mah Bow Tan.
ZEB underwent a very energy efficient re-design of the façade, roof, M&E system and other building components to reduce its energy needs. At the same time, natural and renewable energy were harnessed from the environment.
The Zero Energy Building is expected to be about 40 to 50 percent more efficient than an office building with a similar layout.
Although the building is connected to the grid to cater for variability in the supply of solar energy, it is expected to generate as much electricity as it consumes over a typical year.
Design features include, a thoughtful facade to eliminate heat loss or retention and natural ventilation means energy will not be consumed through air conditioning.
Air conditioning is also adjusted according to the number of people using the space, the indoor temperature and the CO2 levels.
Lights are activated only when users enter a room and light intensity is adjusted according to daylight intensity. So if there is abundant daylight, the artificial lights will automatically be dimmed.
To achieve energy self-sufficiency, the ZEB is powered by a broad spectrum of solar panels installed at many locations in the building.