Green Star Building Technologies Framework
To boost use of natural elements and enhance the performance of a building green technologies should be adopted for any design. Performance is measurable through continued energy use reduction, water use reduction and improved health and well being of occupants.
The Green Building Technologies industry in East African is ripe for expansion due to rising demands for higher construction standards and better performance buildings. The “green” trend driving this market growth is rooted in:
- High energy costs,
- Declining fresh water sources,
- More stringent environmental regulations by governments,
- Rising cases of chronic health conditions and hospitalization bills.
Some practitioners assume that bolting ‘green’ technologies on a building results in a green design. This misconception leads to the common perception that green buildings cost more than conventional construction.
A good design must respond to the basic human needs at varying environs, for instance, from Lodwar, Kisumu, Mombasa to Nairobi. Even within Nairobi the micro-climate at JKIA and Karen are notably different. A building’s design should be responsive to the particular elements to satisfy how we perceive built up environments using the five senses of taste, touch, smell, hearing and vision. A sustainable comfortable indoor should consider elements such as daylight and natural ventilation. Low operational cost is a well sort after factor of green buildings.
Green building technologies require close collaboration between the different professionals in the design team. The complexity of designing buildings with reduced exposure to various hazards should not be underestimated.
Studies show that performance of employees in certain commercial buildings can be directly linked to the sick days a company reports. Building design has a profound impact on human health at home, school and the workplace.
Building users have varying tastes and needs. The approach to green building technologies has to be based on each project’s brief rather than copy paste “here’s what I made earlier” approach.
During the design process, passive design principles should be adopted first, active green building technologies can then be integrated. In this case big does not necessarily equal best performance, the approach for green building technologies is to reduce demand, then select high efficiency equipment and last but not least regular monitoring and re-commissioning of the systems for optimum performance during the building life cycle, including decommissioning.
Green building technologies include, but are not limited, to the following which are categorized in their use within the Green Star SA-Kenya green building rating framework.
Energy Efficient Artificial Lighting
Interior LED bulbs and fixtures produce light quantity and quality that is comparable to fluorescent, with less energy, thus lowers utility bills. One compact florescent bulb will pay itself back over ten times over the course of its life through reduced energy use.
Solar hot water systems.
Dwelling designs that reduce greenhouse gas emissions associated with domestic hot water. Hence reduced utility costs while contributing to the sustainable development.
Energy Efficient Appliances
Refrigerators and freezers are among the largest users of electricity in most homes. They can account for up to 25% of household energy use. Energy Star appliances use 10-15% less energy and water than standard models. Check with the local utility company for rebate programs.
Monitoring and Re-Commissioning
Intent on supporting the design, construction, and operation of a building that meet the project’s energy, water, indoor quality and durability requirements. An integrated Building Management system that delivers the required reports for purposes of billing and energy management requirement by the Energy Regulatory Commission (ERC). Benefits include an action plan for checking operational deficiencies and reduced error duplication. This creates a platform for performance reports and cost savings accounting.
RENEWABLE ENERGY SYSTEMS
Photo-voltaic power systems are generally classified according to their functional and operational requirements, their component configurations, and how the equipment is connected to other power sources and electrical loads.
The two principal classifications are grid-connected and stand-alone systems. Photo-voltaic systems can be designed to provide DC and/or AC power service, can operate interconnected with or independent of the Kenya Power grid, and can be connected to provide power directly to the building and or include energy storage systems such as batteries for energy use when there’s no daylight.
The size of the photo-voltaic system is determined by the amount of electricity required to be generated, the available space for mounting the photo-voltaic panels and amount of sunlight hours/ irradiation available on the particular site.
Carry out a feasibility study prior to adopting this technology as the return on investment is dependent on the project needs. The feasibility should include, as a minimum, consulting fees, capital cost as well as ongoing maintenance and decommissioning costs in comparison to buying electricity from the grid. Storage batteries versus cost of generators should be interrogated for places where generators are used as backup power.
Wind energy technologies can be classified into two categories – macro wind turbines that are installed for large-scale energy generation such as wind farms, and micro wind turbines used for local electricity production. Micro wind turbines are suitable for application at the building scale and are called ‘building-integrated wind turbines’. These almost non-existent in Kenya.
The main components of a wind turbine include blades, a rotor, gearbox and generator. Small wind turbines were originally designed with a horizontal axis, also known as HAWTs. To reduce the need for a high tower, and for aesthetic reasons, vertical axis wind turbines (VAWTs) become increasingly popular for integrated building applications. Furthermore, VAWTs are also quieter than HAWTs during operation.
Newer wind turbines designs improved reliability and efficiency at low capital cost and wind speeds. Wind turbine blades are now designed with lightweight materials and aerodynamic principles, so that they are sensitive to small air movements. In this way, electricity can be generated with wind speeds as low as a few meters per second.
Energy-modeling is the virtual or computerized simulation of a building or complex that focuses on energy consumption, utility bills and life cycle costs of various energy related items such as air conditioning, lights and hot water subject to use of the building. It is also used to evaluate the payback of green energy solutions like solar panels and photovoltaic cells, wind turbines and high efficiency appliances. This will predict monthly consumption, annual energy cost, annual carbon emissions, as well as compare different options and determine the payback period.
Water Efficient Fixtures
New toilets use 1.6 gallons per flush compared with old toilets that require 5-7 gallons per flush. Flow reducers fit into the aerator at the tip of the faucet and reduce the rate of water flow through the faucet. Low-flow toilets can save up to 22,000 gallons of water per year for a family of four. Flow reducers can cut water usage of faucets and showers by as much as 40% with little noticeable effect to the water user.
Efficient Irrigation Systems
Low-water landscape designs (such as xeriscape) reduce water use by emphasizing native and/or drought tolerant plants, eliminating turf areas, and minimizing maintenance. Efficient irrigation systems, such as drip and micro irrigation place the right amount of water directly at the base of each plant reducing water waste. Reliance on portable water for irrigation is discouraged while rain water and recycled water is preferred.
Efficient landscape and irrigation systems help plant growth healthy by eliminating over watering or excessive drying. They lower water bills and over dependence on water supply infrastructure.
Low VOC materials
You are encouraged to specify no-VOC brands that are virtually free of volatile organic compounds (VOCs),
Organic chemicals are widely used as ingredients in household products like paint, adhesives, cleaning supplies. These can cause irritations, loss of coordination, and potentially damage the liver and central nervous system caused. VOCs can bond with other pollutants and create ground-level ozone.
Particleboard typically contains formaldehyde, which can off-gas for 10-15 years. EPA ranks formaldehyde as a probable human carcinogen. Exposure can cause eye, nose and throat irritation, skin rashes, headaches, nosebleeds and nausea.
Elimination of formaldehyde-based materials reduces exposure to residents, particularly children, who are most susceptible. Sealing with a flat, latex- based primer or other suitable material can prevent off-gassing of formaldehyde.
Carbon monoxide detectors monitor the level of this gas in individual dwelling units. Detectors can reduce harmful human health effects of carbon monoxide, a common indoor air pollutant created by the combustion of natural gas from stoves and heaters.
The use of Forest Stewardship Council (FSC) certified timber aims at appreciating the value of all certified timber products and promote green building supply chain and in preserving forests. Reduced deforestation through a controlled framework hence the preservation of natural water towers.
The reduction in embodied energy and resource depletion associated with use of virgin steel recommended by use of locally manufactured steel with recycled content. Steel should represent more than 1% of the project contract value. Encourage recycling of waste metal contributing to cleaning of the environment around us.
Distant transportation of materials to a project site is discouraged. A percentage greater than one percent of the total contract value should be represented by materials or products that have been sourced & manufactured within the East African region as is required by the Green Star SA Multi-Unit residential contextualization report.This accounts for less carbon emissions and support for local industries.
Air Cleaning Paint
This revolutionary air purifier paint absorbs, filters and neutralizes chemicals and pollutants, solvents and VOC’s from the atmosphere in your home down to approximately one part per million. It meets the VOC limits set by international paint Eco labeling standards transforming painted areas into air purifying systems.
In the development of Green Buildings the Life Cycle Assessment (LCA) is an integral part of the process as it allows for a holistic approach of the development. LCA involves assessing the environmental aspects and potential impacts associated with the product or process by:
compiling an inventory of relevant energy and material inputs and environmental releases;
evaluating the potential environmental impacts associated with identified inputs and releases;
Interpreting the results to help you make a more informed decision.
When first conceived, it was predicted that LCA would enable definitive judgments to be made on products. That misplaced belief has now been discredited. In combination with the trend towards more open disclosure of environmental information by companies, and the desire by consumers to be guided towards the least harmful purchases and ensuring the most sustainable products are integrated into the design, the LCA is a vital tool.
Green is good. It’s good for the environment, and it’s good for business. Having a “green building” means constructing and operating it in a way that benefits the environment and also benefits the triple bottom line. Tenants are happier, healthier, leasing rates are higher, and operational expenses are lower.
Green buildings in Kenya take advantage of the moderate Kenya climate, with sunshine available most days of the year. Integration of green building technologies meets the needs of the present without compromising the ability of future generations to meet their own needs. The last thing Kenya needs is a Vision 20future to rectify what we presently design.
Elizabeth Wangeci Chege,
CEO WEB Limited
Chairperson Kenya Green Building Society.