Sustainable households

It is estimated that 10% of an average home’s electricity bill is standby power, that is the appliance is using power even though the device isn’t in use (for example televisions, DVD players, set top boxes, game consoles, stereos, computers, mobile phone charges). A typical household in Albury could save $340 per year by turning appliances off at the wall when not in use. Find out how much your appliances are costing by borrowing the libraries Save Power Kit.

When purchasing a new appliance check out its Energy Rating. Assuming you use the appliance per its description below the stars, simply divide the energy consumption figure by 4 and it will give you the rough cost to run the appliance per year. This works as energy rates range from 20 cents to over 30 cents so using 25 cents gives a rough estimate.

When selecting your block, consider:

• Rectangular blocks that enable living areas to face north;
• Are the sun’s rays to the block impacted by the lot size, orientation, slope of the site and vegetation or adjoining buildings? Solar access to the block is important for passive heating/cooling, solar hot water and / or a solar PV;
• Check how the terrain or vegetation could affect air movement and solar access;
• Potential overshadowing from height and spread of trees, and neighbouring houses;
• The benefits from existing vegetation relating to wind protection and summer shading.

Lighter colour roofs typically have a low solar absorptance compared to darker coloured roofs. Solar absorptance is a measure of how much solar radiation the roof absorbs (0 indicates no roof absorbance and 1 indicates the roof absorbs 100%). Houses with a low solar absorptance roof heat up less in summer months and thus require less air conditioning.

Examples of the solar absorptance of roofing products include:

Colorbond.

Bristile roof tiles

Harmony roof tile

The smaller a home’s footprint, the easier it is to achieve high energy efficiency.

Building or renovating your home is a chance to make your life significantly more sustainable right from the outset – aspect, insulation, windows and building materials can all have a substantial impact on your home’s environmental footprint. Designing these features well will set you up for a life with lower energy bills and more comfortable living spaces. And, as always, the smaller a home’s footprint, the easier it is to achieve high energy efficiency.

The following is taken from Your Home and should be provided to your draftsperson or architect early in the design phase to discuss options for your new home.

• Use high levels of well-insulated thermal mass.
• Use north-facing, high thermal mass living areas with passive solar access.
• Select a site exposed to cooling breezes, and design to exclude adverse winds while allowing for cross-ventilation and night purging.
• Design to capture cool air drainage on still nights (cool air flows in similar patterns to water as surface temperatures drop due to night sky radiation).
• Limit external wall area.
• Choose compact floor plans with central, closable stack ventilation shafts or solar chimneys.
• Consider central courtyards with evaporative cooling water features to allow night cooling with wind protection.
• Use mechanical ventilation in ceiling spaces to ensure high level flows of cooler (south-side) air in summer and a complete seal in winter.
• Provide screened, shaded outdoor living areas that allow winter sun penetration.
• Use garden ponds and water features outside windows to provide evaporative cooling.

Windows and shading

• Avoid overuse of glazing.
• Use different glazing types for each façade; low U-value glazing is essential in all cases.
• Double glaze living areas and consider using it in bedrooms.
• For north-facing windows select high SHGC glazing and passive shading.
• For east and west façades select low SHGC coatings (e.g. low-e).
• South-facing glass should have low U-value and high visible light transmittance.
• Thermally improved or insulated frames (timber or PVC) are important.
• Passive solar shading to northerly windows is critical.
• Shade all east and west glass in summer.
• Consider adjustable shading to allow variable solar access in spring and autumn.

Insulation

• Refer to Insulation for appropriate insulation levels in each climate zone and recommended minimum insulation levels.
• Use bulk and reflective insulation in ceilings, and bulk or reflective insulation in walls.
• Provide external insulation to all thermal mass.
• Insulate under concrete slabs if using in-slab heating.
• Insulate elevated floors (concrete or lightweight).
• Ensure all spaces are effectively air sealed.

Heating and cooling

• Use evaporative cooling and passive solar heating in living areas.
• Provide ceiling fans in all living and sleeping spaces.
• Consider active solar heating and reverse night cooling connected to in-slab hydronic systems in more extreme regions.
• Check typical heating and cooling requirements in the local area to determine appropriate passive heating levels (consult your local thermal performance expert).

Construction systems

• Prefer high thermal mass construction.
• Use earth coupled slabs.
• Choose light coloured roof materials

Eaves provide the least expensive method for shading on northern elevations. A common error with eaves places the top of the window in permanent shade but this can be easily corrected in the design stage.

If considering supplementary heating and/or cooling for your home, select a system that suits your needs and is energy efficient. To maximise your home’s comfort and energy savings ensure that draughts around doors and windows are sealed, roof and walls are insulated and hang heavy curtains with pelmets.

Keep room temperature between 18-21^oC in winter and 23- 26^oC in summer. Each degree change from these recommendations can increase the heating/cooling of your home up to 15%.

For more information about heating and cooling options visit energy.gov.au.

Check out the different options and consider your household size, up front purchasing cost and operating costs, space available and energy sources available to you.

A HWS with storage can waste 30% of the energy it uses due to heat loss from the tank and hot water pipework. To minimise the loss of hot water, locate wet areas near the kitchen where frequent small amounts of hot water are used.

When determining the best hot water service for your home consider:

• Household size, space available, upfront and operating costs, solar access and energy sources available;
• Ensure roof pitch and orientation is suitable for a future solar water heater. Solar boosted solar electric or gas booster solar water heaters generate fewer greenhouse gas emissions; and
• Solar and heat pumps may be more suited where natural gas is not available, as LPG can be expensive if a lot of hot water is used. A heat pump can provide a 45% reduction in running costs. For more information read the Heat Pump Water Heater guide for Households;
• If your system has a storage tank, ensure it is sized appropriately. Too small and you’ll run out of water, too big and you’ll have excessive running costs;
• Install water efficient showerheads as showering uses the most hot water in an average household (and if you buy a continuous flow HWS make sure the water efficient showerhead is compatible).

Also be aware if installing mixer taps these can waste hot water if not used correctly. Be sure to leave the handle in the cold position.

Household lighting costs are decreasing as light emitting diodes (LEDs) are replacing halogen and incandescent lights. LEDs save money as they use up to 75% less energy and need replacing less often.

When designing your home consider:

• How to minimise artificial lights during daylight hours;
• Avoid rooms with a dark interior as this will absorb light and require more artificial light to be provided;
• General lighting and task lighting for each space;
• Locating switch so they are easily turned off when leaving the room;
• A lower wattage light as this will save energy costs compared to dimming;
• Energy efficient LEDs over lighting types that are be phased out; and
• Sky lights as these can provide three times as much light into a room compared to a vertical window.

Take advantage of the climate to maintain a comfortable temperature range in your home without (or greatly reduced) supplementary heating or cooling and save up to 40% of energy use in Australian homes or nearly $1,370 per annum in Albury.

For more information visit Your Home

If you’re not installing solar or solar hot water during construction, ensure pitch and orientation allows for installation in the future.

Panels perform best when they are installed at an angle as they capture more energy from the sun. The added benefit is the angle also assists rain to wash off dust and grime.

A flat roof will require solar panels to be mounted to at least 10 degrees to avoid rain damage to the panels. However, the additional cost of adding a frame to a flat roof to tilt the solar panels is generally not cost effective.

Solar panels used to be installed facing north to maximise daily production. However, if you want to save the most on your electricity bill, you may be better to have some  panels facing partially east and some partially west so that the panels are generating electricity from sunrise to sunset.

Electricity prices have increased significantly over the past few years and one method to reduce your bills further is to install solar. Solar should be considered after implementing energy efficient options identified above as this will reduce the size of the solar system required and thus its cost and how long it takes to pay it off. Generally, a warranty on a PV system is for 20+ years and a system can be paid back in under 5.

For more information read the Clean Energy Council’s Guide to installing solar for households

Draughts can increase heating and cooling costs by 25%, or $340 per year for an average 4-5 person Albury home. These costs can be reduced by installing draught seals around doors and windows. Internal doors can also have draught seals to minimise heat loss between rooms that are air conditioned or heated with those rooms not in use. This is a cost effective way to save energy and can easily be completed on existing homes.

The other benefit is that it stops windows from rattling!

Position windows and or doors on more than one side of a room or house to enable natural cooling by cross ventilation.

Use internal lined curtains or close-fitting Holland and or roman blinds with pelmets. Vertical blinds, conventional or timber venetians are generally not as good at keeping the heat out during summer or warmth in during winter.