If you’re renovating or building a home, you have the perfect opportunity to save money by making it as comfortable and energy-efficient as possible. An energy-smart home looks just like any other but uses the best combination of building orientation, wall and ceiling insulation, efficient heating, cooling, hot water, lighting and appliances to reduce household energy consumption by up to 40 per cent. Because energy-smart homes use significantly less energy than conventional homes they can save you hundreds of dollars on your utility bills and help protect our environment by reducing greenhouse pollution. More than 40 million tonnes of harmful greenhouse gas emissions are attributed to the electricity consumption of Australia’s six million homes every year. In other words, 25 per cent of the total amount of greenhouse gases is produced by the household use of electricity and gas. Reduced domestic energy use will have a significant impact on greenhouse gas emissions, thereby reducing the impact of climate change.
When renovating your home, consider the following factors:
The main consideration when selecting building materials is their thermal mass, which refers to a heavyweight material’s ability to store thermal or heat energy. When used in the floor or walls of a building, materials with thermal mass can:
* Absorb heat during winter days and release it back into the living spaces during cooler periods; and
* Absorb heat from the building during summer days, having cooled down via natural ventilation during the previous cooler evening.
Materials that can provide thermal mass include concrete floors and masonry walls such as cavity brick or feature brick.
Lightweight materials such as timber or plasterboard can also be used internally to allow rooms to heat up and cool down quickly — useful in rooms requiring occasional heating, or if you live in a tropical climate and cool your home by opening doors and windows. The building materials you choose will be influenced by your area’s climate. To find out which materials best suit your region, contact the Energy Smart Information Centre (ESIC) on 1300 138 638 (NSW) or (02) 9249 6100 between 9am and 5pm, Monday to Friday.
INTERNAL PLANNING AND ROOM PLACEMENT
When deciding where to place rooms in your home, your main goal should be to maximise the amount of sunshine available to assist with warming the house. This should be balanced with appropriate window shading and ventilation to keep you cool in summer. Some tips for making the most of available sunlight include:
* Living areas such as the family room, kitchen, lounge and dining room should be placed on the northern side of your home. If there is insufficient space for all of them, at least place day living areas to the north.
* Bedrooms can be located on the southern or eastern sides, although bedrooms used for play or study may be located on the northern side.
* Service areas (eg bathroom, laundry, garage) are usually located on the southern or western side, as they have minimal thermal comfort or heating/cooling requirements.
* Group together rooms that use hot water (kitchen, bathroom, laundry) to minimise heat loss in pipes.
* Create zones by grouping together rooms with similar uses, separated by doorways.
* Avoid open-plan living areas or high ceilings as these can lead to high heating costs. Maximum ceiling height should be 2.7m.
Circulation zones (eg entry, corridors, halls) have minimum thermal comfort requirements and will not generally benefit from improved sunlight, but can impact on other zones if they are open between those zones.
HOOSING A COOLING SYSTEM
Keeping your home cool in summer doesn’t have to be expensive. Stop the heat getting in and you can avoid purchasing unnecessary cooling equipment with high running costs. By paying close attention to all of the items described below, you can reduce heat entering your home by up to 90 per cent:
* Insulation in ceilings (and walls and floors if possible).
* Draught sealing around windows, doors and any other gaps.
* External shading to north, east and west windows.
* Ventilation to allow cool outside air into the house.
CHOOSING A HEATING SYSTEM
An energy-efficiency heating package can use 40 per cent less energy! An effective and economical heating system is more than just a good heater; it’s a heating package that should always include:
* Insulation in ceilings, walls and floors where possible.
* Sealing off draughts.
* Effective window coverings.
* Zoning of living and sleeping areas.
* Appropriate and efficient heater(s).
* Wise, efficient use of your heating package.
CHOOSING A HOT WATER SYSTEM
Hot water can account for more than a third of your household’s energy costs, so choosing the right system for your needs can considerably reduce your energy bill. There are two types of hot water heaters: storage and continuous flow. Storage water heaters heat and store water in an insulated tank ready for use. They operate most economically on solar energy, natural gas or off-peak electricity. Continuous flow (instantaneous) water heaters heat water as it is required and therefore cannot run out of hot water. They operate most economically on natural gas. Both are suitable for most households. Your decision should be based on the size of your household, purchase and installation price, the unit’s efficiency and running costs, and the life expectancy of the unit. Purchasing an energy-efficient solar or heat pump water heater can save you up to $2000 over 10 years and will reduce the greenhouse pollution attributed to your hot water system by up to 70 per cent. A high-efficiency gas water heater will save up to $650 over 10 years. Federal government rebates are available for solar and heat pump systems.
Insulation provides a barrier to heat flow into and out of your home. A well-insulated home is up to 10 degrees warmer in winter and up to seven degrees cooler in summer and can save as much as $300 per year in reduced energy costs. Where you insulate will govern how effective your insulation is. Insulated ceilings can potentially save 20 to 40 per cent on heating and cooling costs; insulated external walls can potentially save an additional 10 to 60 per cent on energy costs; insulated flooring can save possibly a further 5 to 10 per cent. Existing homes can easily have insulation installed in the ceiling and under timber floors if crawl space is available. Walls can be insulated during recladding or replastering. Specialised products are also available to insulate existing walls.
There are two types of insulation: bulk and reflective.
Bulk insulation works by reducing the amount of heat that transfers through a roof, wall or floor, in the same way a jumper keeps you warm. The jumper is full of holes, or air pockets; these air pockets trap the heat generated by your body. The importance of air pockets in bulk insulation highlights why it’s vital not to compress insulation. Compression reduces the volume of air, thereby reducing the ability of the material to resist heat transfer. Examples of bulk insulation include batts and loose-fill insulation.
Reflective insulation works by reflecting large amounts of heat away from its polished metallic surface. Note that reflective insulation must face a sealed airspace at least 25mm wide. Reflective foil is often supplied in rolls; however, other examples include concertina foil batts and multi-cell reflective batts. When choosing insulation, the most important factor to consider is its R-value. The R-value is a measure of the material’s resistance to heat flow, and therefore its performance. The higher the R-value, the greater the resistance to heat transfer and the greater the energy savings. Australian Standards recommend different insulation levels for different locations based on climatic differences as well as energy and insulation costs.
Lighting costs the average NSW household up to $100 each year. Careful selection of lamps and fittings can cut your energy costs for lighting by more than half. The higher the wattage of a lamp, the higher the running cost. Compact fluorescent bulbs burn as brightly as incandescent bulbs, but they require less power to do so — therefore, they have a lower wattage and lower running costs. Each compact fluorescent light bulb you install can save you $50 and half a tonne of greenhouse gas over the bulb’s lifetime. Compact fluorescent light bulbs cost more than regular incandescent light bulbs, but can last up to 10,000 hours, which means you won’t have to worry about replacing them as often. And, despite their rectangular shape, they still fit most light fittings. They are ideal for rooms where lighting is required for long periods of time, such as in the living room or kitchen.
SOLAR POWER SYSTEMS
C:It’s never been easier to go solar! Cash-back rebates are available now for solar power systems. A solar power system, which allows you to generate your own clean electricity from sunlight, consists of:
* Solar panels, either mounted on the roof or the building façade (panels can also replace the roof material).
* An inverter, which turns the electricity from the panels into a form you can use for your home.
A grid-connected solar power system generates electricity during the day and stores it in the electricity grid (the poles and wires on your street). The electricity generated in excess to your home’s needs is delivered to the grid. In remote areas, batteries are used for storage instead of the grid.
Solar power does not produce air, noise or water pollution, or visual intrusion. A solar power system is an attractive way to add value to your home. In remote areas, solar power is a cost-effective alternative to connecting to the grid. Solar power is a proven technology, able to generate electricity for 20 years or more without intervention. Rebates on solar power systems for homes, businesses, schools, and investment properties are now available from the NSW and Commonwealth Governments through the Sustainable Energy Development Authority. Rebates will cover between 10 and 30 per cent of the cost of a new solar power system.
Green Power is electricity generated from clean renewable sources such as the sun, wind, water and organic matter. Most people do not realise that over 90 per cent of their electricity is generated by burning coal, creating greenhouse gas pollution that contributes to global warming. By choosing a government-accredited Green Power product, you can have up to 100 per cent of your household’s energy usage generated from renewable sources. Choosing Green Power in your home can reduce greenhouse gas emissions equivalent to taking two cars off the road each year! As a result of the growing demand for Green Power, over 100 new approved renewable energy projects have been installed in Australia since 1997. The Green Power tick is your guarantee that your contributions are helping facilitate the installation of new sustainable energy projects in Australia. Energy suppliers’ Green Power products are independently audited so you can be sure your money is being well spent. Deregulation of the energy industry means all customers in NSW can choose who to buy their energy from. For more information and to find out how to subscribe to Green Power, phone 136 206, visit www.greenpower.com.au or ask your energy retailer whether they offer a Green Power product.
FOR MORE INFORMATION
Call the Energy Smart Centre (ESIC) on 1300 138 638 (NSW) or (02) 9249 6100 between 9am and 5pm, Monday to Friday. Call Greenpower on 136 206 or go to www.greenpower.com.au.