If you’re anything like me, you’re increasingly working from home, one that was built before energy efficiency measures were introduced in Australia. With temperatures along the east coast

plunging and power bills skyrocketing, heating (and cooling) our homes is an energy intensive, expensive affair. Almost 8 million homes across Australia lack sufficient insulation, use

sub-par heating and cooling equipment, or are badly designed. Indeed, these 8 million pre-energy rated homes account for 18% of Australia’s greenhouse gas emissions. And research finds 26%

of Australians across all housing types can’t stay warm at least half of the time during winter. Retrofitting this housing stock to be more energy efficient is essential to successfully meet

comfort: determined by the temperature, humidity, air flow and a person’s physical condition * energy consumption: the amount of energy we use, and the energy used in manufacturing,

transporting, constructing, maintaining, and removal of materials to build our homes. 1. VISUAL COMFORT It’s vital to understand how much sunlight the outside and interior of your home is

exposed to. One can, accordingly, re-organise interior functions based on the demand for lighting, heating or cooling needs. During summer, spaces used often during the day, such as your

home office, could benefit from being in places that receive less direct sunlight, so are cooler. In winter, consider moving your home office set up to a room with higher levels of direct

sunlight, where it’s warmer. This will naturally reduce the amount of energy needed to cool or heat these rooms while allowing for comfortable working conditions. Other ways we can find more

visual comfort include modifying the size of windows and skylights to let in more sunlight. To diffuse harsh lighting, consider adding screens, sun baffles, overhangs, or pergolas over

windows. You can also replace your lights with LEDs equipped with linear controllers and motion sensors in places where lights tend to be left on. LEDs use around 75% less energy than

halogen light bulbs. 2. THERMAL COMFORT Older Australian homes are incredibly draughty, and a lot of the energy we spend cooling or heating our homes escapes outside due to poor insulation.

Retrofitting to improve your home’s natural ventilation can reduce the number of times you need to switch on the heater or air conditioner. Sealing outside and internal surfaces until

they’re airtight is crucial. Different surfaces – whether walls, floors or ceilings – require different methods, types and thicknesses of insulation. ------------------------- _ READ MORE:

IF YOU'RE RENTING, CHANCES ARE YOUR HOME IS COLD. WITH POWER PRICES SOARING, HERE'S WHAT YOU CAN DO TO KEEP WARM _ ------------------------- Walls, for instance, require a

“blow-in” method. This can involve installing cellulose foam or glasswool (made from fibreglass) into the wall, via a small hole through the wall cavities (for cellulose foam) or laying

glasswool batts in wall cavities. Floors, on the other hand, can require insulation panels fitted between timber or steel supports or foam boards. Also important is to choose materials and

methods that maximise insulation while minimising thermal bridging. A thermal bridge is a weak point where heat is lost, such as wall intersections, connecting points of mounting brackets,

and even penetration points of electric cables. Between ten and 35% of the energy we spend cooling or heating our homes escapes through single glazed windows and doors. Installing double or

triple glazed windows and doors will go a long way to keep temperatures more stable inside. It’s worth noting the energy performance rating systems on measurement labels, which are often

attached to window and door units you can buy in stores. Ultimately, a combination of improved natural ventilation and mechanical ventilation (such as air conditioners as fans) can result in

considerable energy savings – up to 79% in some instances. 3. ENERGY CONSUMPTION While the above strategies will result in significant energy savings, it’s also vital to consider the energy

required to produce and manufacture retrofitting materials. Consider using salvaged or recycled materials where possible, or choosing locally made products which avoid emissions associated

with transport. Effectively installing solar panels can offset this “hidden” carbon. Let’s say you’ve done all you can to lower your home’s carbon footprint – you’ve rolled out insulation,

installed double glazed windows and made the most of sunshine. ------------------------- _ READ MORE: STOP REMOVING YOUR SOLAR PANELS EARLY, PLEASE. IT'S CREATING A HUGE WASTE PROBLEM

FOR AUSTRALIA _ ------------------------- You can then calculate the energy you still use to heat or cool your home. This number will determine how many rooftop solar panels you should

install to break even, rather than simply installing as many panels that can fit. This will not only save you money, but also minimise waste. Researchers estimate that by 2047, Australia

will accumulate 1 million tonnes of solar panel waste. It’s worth opting for solar panels with micro-inverters, which capture optimal energy performance per panel while allowing you to add

more panels in future if needed. Another option is to use air-source heat pumps, which absorb heat from outside and bring it inside (like a reverse air conditioner). These can take the form

of mini-split heat pumps for individual rooms, or multi-zone installations. They can sense indoor temperature, and operate at variable speeds and heating or cooling intensity, which means

their energy performance is very efficient. My research finds well-planned use of such systems can reduce the energy used for heating by 69% and cooling by 38%. IT’S WELL WORTH THE EFFORT

These retrofitting ideas might seem expensive, or take too much time. However, they’ll often save you money in the long run as energy prices become increasingly uncertain. You can look to

Every Building Counts, an initiative by the Green Building Council and the Property Council of Australia, which provides practical plans for emission reduction. Australia can also learn from

ongoing efforts by the Energiesprong network in the Netherlands. This network is industrialising energy efficiency with prefabricated retrofitting building elements. Some initiatives

include lightweight insulated panels that can simply be placed in front of existing walls of homes. These panels are precisely fitted after carefully laser scanning a facade and robotically

cutting openings to match existing homes. Harnessing contemporary technology is vital for a speedy net-zero transition. ------------------------- _ READ MORE: BIDEN JUST DECLARED HEAT PUMPS

AND SOLAR PANELS ESSENTIAL TO NATIONAL DEFENSE – HERE'S WHY AND THE CHALLENGES AHEAD _ -------------------------