Home Energy Efficiency

To prove my point, Ben and I went for a walk about a month ago, for about 1 km where there is a new housing development being built. This new estate seemed to go on for miles, but we had a good time and found lots of junk left behind from builders and utility installers. Telstra leaves so much PVC piping laying around after laying their phone cables, I could have put all the pipes together and formed a length about a kilometre long! Anyway back to the subject at hand.

All the housing blocks were small in size with the biggest being about 590 sqm in size. Not much of a back yard to grow vegetables in, especially if they build another McMansion on the site. On the way back we stopped off at the two display homes and had a look around. I was gob smacked by the amount of halogen down lights in every room! At 50 watts a piece and 10 watts for the transformer that is 60 watts per light. In the kitchen/living area I counted 22 down lights that were on one circuit alone. So at the flick of a switch there was 1320 watts worth of lighting to cook your dinner. I couldn’t believe it. There were no energy efficient lighting in these houses whatsoever, and they were hot as well. The outside temperature was about 20C on this day, and the inside thermostat was set on 25 degrees. Ludicrous. The heat from all of those lights would have been enough without having the central heating turned on! What really gets to me, is that people still want to buy these types of homes, even as energy and fuel prices rise.

In the bathrooms, there were about 10 down lights, plus two heat lamps and a 100 watt light. The heat lamps are usually rated between 250 and 300 watts each. So if you had all the lights on in the bathroom for just 30 minutes a day you would use about 650 watt hours. Multiply that over a year and there is 237 kWh each year just in bathroom lighting! By changing the halogens to LED equivalents that are rated at 3 watts and just as bright, and resist the temptation to use the heat lamps, you could save 226.1 kWh per year which at the price of $0.15 per kWh is a cost avoidance of $33.92. Multiply this by changing out all the house lighting to energy efficiency and the yearly savings would be quite substantial. All this from lighting alone. If you fit a skylight in the darker rooms, you also negate the need for artificial lighting even on the cloudiest days. Just think of the other savings available, if these houses were smaller and fitted out with other energy efficient appliances. For more tips on energy efficiency have a read of this previous blog and the second part about the subject written back in February this year.

Whilst on the subject of energy efficiency, other things that I notice that were missing on these display homes were simple things like wide eves to block the sun in summer from entering the windows, no external awnings to shade the north facing windows, too much single glazing and large areas of south facing glass looking out onto the non-existent garden. There would have been no way you could have used passive heating to warm this place up in winter because all of the northern windows were small. I also noticed that the installed dishwasher had a two star efficiency rating, and was a very cheap model. The only real effort to create some sort of efficiency was the solar hot water system and ceiling insulation, but I believe that those things are part of the existing building regulations for 5 star homes already. There will certainly be a savings in natural gas for hot water and heating, but with the inside temperature set at 25 degrees it would negate any of the savings from these systems. For every two degrees you raise the temperature of the heating system increases your green house gas emissions by 890 kg and increases your heating bill by up to $139. See more tips for staying warm, but still reducing your energy consumption visit resourceSmart.

Aim for an internal temperature between 18-20 degrees for a comfortable home. We do, and it is very comfortable in our house. It is currently 11 degrees outside, but a toasty 19 degrees inside, and we haven’t had the heating on at all today. If it gets a bit cooler, we tell the kids to put their dressing gowns and slippers on! A little bit of passive heating from the northern window, and good draft proofing and roof insulation has reduced our heating bill so far this year.

The simple solution would be to buy an established house and retrofit it with good insulation, a bit of draft proofing and energy efficient appliances, instead building these huge monstrosities. Less resources get used all around, and far better for the planet! Furthermore, it would be good to have a decent renewable energy feed in tariff in this state, to promote the widespread installation of renewables, therefore negating the requirement to build more dirty coal fired power plants in the future. I had to have a final dig!