Energy Efficient homes use energy efficiently and they are built to minimize the use of energy. Using less energy will reduce energy costs and greenhouse emissions.
ENERGY STAR Program
The ENERGY STAR ® program was initiated by the US Environmental Protection Agency and it was first offered for homes in the US in 1995. Within Canada, ENERGY STAR ® is a voluntary partnership between the Canadian Government and industry to promote energy efficiency and the Energy Star Symbol is used to identify energy efficient products and new homes built since 2005.
The ENERGY STAR rating system has scores from 1 to 100. A score of 50 is the median and a score of 75 or higher means that it is a top performer and it may be eligible for certification. Using this system 0 represents a house with major air leakage, no insulation and high fuel consumption. In other words, a house with poor energy efficiency and high utility costs. 100 represents an airtight and well-insulated house where energy purchased and energy generated, through renewable sources, is equal. Also called a ‘net-zero. Using this system following are a few differentiations:
Energy Rating System
Existing house not upgraded ERS of 0 to 50
Upgraded existing house ERS of 51 – 65
Energy – efficient existing house ERS of 66 – 74
New house to code without energy requirements ERS of 70 – 76
New house to code with energy requirements ERS to 77 – 80
Energy Efficient house ERS of 81 – 85
High performance energy efficient hew house ERS of 86 – 99
Net Zero new house ERS of 100
It is important to note that mandated building code requirements continue to evolve and become more rigorous. As a result ENERGY STAR guidelines for new homes have been modified to ensure that homes that earn the label continue to represent meaningful improvement over non-labelled homes. Pre 2006 built homes are assessed against Version 1 while homes completed after 2012 are assessed against Version 3 of the ENERGY STAR program.
ENERGY STAR Products
An Energy Star product is in the top 15 to 30 percent of its class for energy performance and there are currently more than 70 product categories. Categories include appliances, electronics, lighting, heating equipment, cooling and ventilating equipment, water heaters, windows and doors, office equipment, data centres, and commercial food equipment. Products include dishwashers, refrigerator-freezers, washers and dryers, ceiling fans, air conditioners and heat pumps, ventilating fans, boilers, gas furnaces, geothermal heat pumps, computer monitors, televisions, and windows.
ENERGY STAR Homes
An Energy Star qualified home is a home that is on average 20 percent more efficient that a home built to code. Some features of this type of home include:
• Efficient heating and cooling systems that use less energy, improve comfort and reduce indoor humidity;
• Windows, patio doors and skylights that keep the heat in during the winter and out during the summer;
• Walls and ceilings insulated beyond that required by the Building Code;
• Products used in the home that are Energy Star rated:
• A heat or energy recovery ventilation system that is used in the home to ensure the home has controlled ventilation.
Every Energy Star home is built by builders who are licensed by the Government of Canada, the home is awarded an Energy Star label and issued a certificate by the Government of Canada (Natural Resources Canada). The label is placed on the electrical panel and the certificate is given to the homeowner.
Both ENERGY STAR and R-2000 homes have energy saving features and efficiency. R-2000 homes also have clean air and environmental features that make them some of the most energy-efficient homes on the real estate market. These types of homes offer additional resale value.
Other Energy Efficient Homes
Beyond current ENERGY STAR and R-2000 homes are Solar Ready and Net Zero Homes.
Solar Ready Guidelines have been developed that specify design considerations and modifications that builders can me to new homes in preparation for the installation of future solar thermal systems or a solar photovoltaic system (PV). The design considerations include roof space, Solar Domestic Hot Water (SDHW) and solar PV conduits, plumbing connections to existing hot water heaters, an electrical outlet, mechanical room floor space, and mechanical and electrical room wall space.
Net Zero Energy Homes produce as much energy as they consume on an annual basis. While not currently market feasible due to the large cost of achieving it, initiatives are underway to work towards this goal. This initiative is being led by the CMHC Equilibrium project. CanmetENERGY (of NRCan) is Canada’s leading research and technology organization in the field of clean energy and they have developed the technical approach for evaluating NZE home projects currently underway across Canada. As well, CanmetENERGY using the twin-house Canadian Centre for Housing Technology (CCHT) for the research and testing of residential technologies such as combined heat and power (CHP) systems, fuel cells, solar technologies and heat pumps. The CCHT is a collaborative initiative between the National Research Council (NRC), NRCan, and CMHC.
Energy Evaluation of Existing Homes
Existing homes can also be evaluated using an EnerGuide rating. While most builders are still using the 0 to 100 scale because of incentives associated with that system, within British Columbia (and a few other provinces) a new energy use-based rating is available. The EnerGuide Rating in Gigajoules per Year demonstrates the energy performance of a home. The EnerGuide Rating calculation uses standard operating conditions for things like hot water consumption, thermostat temperatures, and the number of occupants to ensure the rating focuses on the house, rather than the occupants’ behaviour. This makes it easier to use the rating to compare the energy usage of one house to another. Your home’s annual energy use, as reflected on your utility bills, is not expected to match your EnerGuide Rating or your Estimated Household Energy Use. A typical new house is the reference point against which to compare your rating. It is a version of your house as if built to typical new construction standards for energy performance. An EnerGuide evaluation of a home will show the home’s rating and that of a typical house. A rating of 0 is the best. The lower the number the better the energy performance of a house.