A short newsletter giving practical advice on minimising your energy for heating and cooling focusing on low cost easily implemented ideas.
For full details visit http://www.coolmax.com.au
Is my exhaust fan costing me money?
NSW to spend $5 billion to cope with air conditioners!
Keep comfortable without any energy use.
Air leakage (often called infiltration) can be around 10% of the heat losses and gains in a house. I have already written about the benefits of sealing doors and timber windows. However one aspect you may not have thought about is losses through exhaust fans when they are not in use. Particularly relevant for kitchen exhaust fans as once you have finished cooking, you don't want to lose air through the fan. Although I wouldn't replace a functional fan, when buying a new fan, consider one that shuts off to seal the room when it is not in use. Shut-off fans are available in ceiling fan configurations as well as wall fans.Back to Contents
Further to my previous comments about the strains air conditioners are putting on electricity networks, a recent report in the Sydney Morning Herald estimates NSW electricity companies are going to have to spend $5 billion dollars (yes that is $5,000,000,000 in NSW alone) just to cope with rising air conditioner use. The money needs to be spent on new generating capacity and transmission lines to cope with the surge in demand during hot weather.
Jeff Angel from the Total Environment Centre has again renewed his call to impose a levy on the sale of air conditioners. This levy would go into a 'Demand Management Fund' to help fund investments to manage the demand. I think this is an excellent idea as currently a person can spend $500 on the purchase of an air conditioner and require society to spend $2,800 to power it. As George Maltabarow from Energy Australia said "...(air conditioners) are used for a small proportion of the time, so you don't recover the capital that you invested through the tariff because the air conditioner is not used enough." Thus currently people who have no air conditioner or a small one are subsidising people with large air conditioners.
Unfortunately Rod King the president of AREMA (the Air Conditioning and Refrigeration Equipment Manufacturers Association) is continuing to bury his head in the sand and reject the calls for a levy. He points to the Minimum Energy Performance Standards (MEPS) as having eliminated the worst energy hogs from the market and the acceleration of the introduction of the tougher new MEPS. Although this is true this in no way makes up for the dramatic growth in air conditioner sales (up 10% per year according to Climate Control News). Rod King points the finger at the 10% of power use due to standby power losses. Although we should minimise standby losses in order to reduce greenhouse gas production, they won't have much impact on the peak energy demand, because at peak energy demand they are nothing like 10% of demand (probably less than 3%) compared to the 50% of demand due to air conditioners.
Although King and others claim a levy won't work, the objective is to provide a disincentive to buying large air conditioners so that people adopt energy minimisation measures to avoid having to buy the large air conditioner. If he thinks this will have no effect on air conditioner sales why is he opposing it?
Paul Fasullo from the NSW National Refrigeration and Air Conditioning Council has said among other things that governments should pay for proper heat load calculations so that people don't waste power on a big cooling system when much smaller units will do. Whether governments will subsidise this I doubt, but certainly this is one of the reasons I developed my SureCool suite of programs to allow purchasers to get the right size air conditioner. My own consulting data shows that conventional rule of thumb sizing techniques can lead to an air conditioner twice as big as you need! Conversely they can also lead in another home to the selection of an air conditioner only half the size required! Either way is a disaster. Find out more at http://www.coolmax.com.au/air-conditioning/buy-selector.htm
Working out what incentives and disincentives should be used to address the problem of air conditioner power draw is a complex issue and if any one has any suggestions I will happily print their idea. So send me a brief e-mail now!Back to Contents
Autumn and spring are the seasons that most people should be able to operate their homes with minimal or no energy use. To do this you need to be somewhat aware of what is happening outside and use windows, blinds, curtains etc to control the energy flows into and out of the house.
If it is a cool day and it looks like getting cold at night then you want to maximise the sunlight into your house during the day by opening curtains and blinds. At night close the curtains and blinds to trap the heat inside. This works particularly well in brick houses although it is less successful in Weatherboard houses as the house can't store the heat during the day to release it at night.
if it is a warm day, close the blinds and curtains on the windows with sun on them, and then in the evening open windows and doors to cool down the house ready for the next day.Back to Contents
Just use the forward button on your E-mail software.
For full details visit http://www.coolmax.com.au/air-conditioning/buy-selector.htm
Clive Blanchard, Consulting Mechanical Engineer
78 West St
South AUSTRALIA, AUSTRALIA 5031
Web page: http://www.coolmax.com.au
Phone (08) 8354 1062