It was nice to see a few people sharing their progress so far during the challenge. I am certainly no saint when it comes to using electricity, however it is due to a few circumstances beyond my control.
Today I discovered that my solar hot water system is broken. Well the little pump that circulates the water up to the flat panel collector is anyway. It was 34 C today, and I expected the hot water to be at least 70 C, but when I washed my hands before dinner, it was only the normal luke warm temperature. I went out and investigated, and discovered that the return pipe was cold, whereby it should have been boiling hot. However the little 7 watt pump was boiling hot, and drawing 75 watts. I believe it is fused/stuffed, so as I believe it still under warranty, I will give the manufacturer a call tomorrow to get it fixed. I estimated that this broken pump has been drawing about 1.8 – 2.0 kWh a day, which could account for the unusually high daily energy usage that we have been experiencing. I am glad I noticed it, and funily enough I dreamed last night that I needed to check it today! Quite a coincidence.
Also, and I have probably shared this before during my Downshift post, but due to Kim having Multiple Sclerosis, it is essential that she keeps cool at all times. Otherwise I come home to a wonderful wife who is totally fatigued at the end of the day because she is trying to soldier on.
So we have ceiling fans on the low setting most of the time in Spring, Summer and some of Autumn, with a small air-conditioner on every few hours on days over 30 degrees C. We also have to keep the swimming pool well maintained so that she can have a dip when she is totally exhausted. You should see the new lease of life she has just after a 1 hour swim in the cool, cool pool. It is amazing!
Therefore I make no apologies for our mid-teen daily kWh usage, which is one of the many reasons I had Solar PV installed (besides the obvious environmental positives) to limit grid utilisation. However, with that said, I have always tried to be as energy efficient with heating and cooling as possible. For those still participating in the challenge, here are today’s tips focusing on this subject.
Did you know that over 39% of the average Australian home’s energy usage is for Heating (90%) and Cooling (10%) and 27% of the homes energy usage is for heating water (electric or gas)?
Cooling
- Keep curtains and windows closed during the day to block out the heat, then open them at night to let in cooler air.
- Fit ceiling fans instead of air conditioners. They use only about one twentieth of the electricity of an air-con. Even a pedestal fan more energy efficient.
- Don’t leave your air conditioner on the highest setting (coolest). The recommended room temperature for summer is 24°C – 27°C. Every 1°C cooler will increase your energy costs by around 10 to 15%.
- Cool occupied rooms and seal off those rooms not in use if you can.
- Turn off your air conditioner for 15 minutes each hour. Or cool your house in the morning and turn the air conditioner off for an hour or so in the afternoon.

Heating
- Install north facing windows (South facing in the northern hemisphere) to catch the winter sun and reduce the amount of energy needed to heat your home. If you can afford double glazing, then it is well worth the investment.
- Make sure that you have as little shading as you can from trees over these windows. Deciduous trees let the light in during winter and shade during summer months.
- Insulate you homes ceiling to at least R2 rating, and if possible any walls you can get to. Good insulation stops heat loss and ingress. The higher the R rating the better the insulation properties.
- Choose the right size appliance for the area you want to heat. Overheating wastes energy, whilst a unit that is too small will struggle (even if running on maximum setting).
- Keep doors to cold rooms, like kitchens, bathrooms and laundries, closed and use heavy curtains on windows. These can prevent up to 75% of total heat loss from a home.
- Stop draughts by sealing unused chimneys with chimney dampers, sealing gaps around doors, and switching off range hoods and exhaust fans. The old door snake/sausage works wonders for drafts under doors.

I thought I would add in hot water heating (due to my own hot water dilemmas) into these tips as it is a form of heating.
Hot water
- Installing a solar-boosted hot water unit can save you up to 90% of your hot water costs on a sunny day.
- Switch off your electric (or gas and solar) hot water unit if you’re going away for a week or more.
- Set the temperature of your hot water between 60°C and 65°C.
- Or, if you have small children, set your bathroom hot water temperature to 50°C – 55°C to decrease the risk of scalding.
- Installing a AAA-rated water efficient shower rose can result in significant savings on both your energy and water bills.
- Take shorter showers. Everyone in our family has a 3-4 minute shower with no issues. You will save energy and water as well.
- Fix that drip! A hot water tap dripping at the rate of 1 drip per second can waste up to $25 worth of hot water in a year.
- Make sure the pipes from your hot water service are insulated to prevent heat loss.
I hope those tips help. The are from just about every state and federal government energy efficiency site I could find. More tips can be found at; www.resourcesmart.vic.gov.au and www.livinggreener.gov.au. Both are great sources of information.
Until next time, keep on saving those Kilowatt Hours!
We are taking the kilowatt challenge but are doing it at a monthly rating because we’re following the Riot for Austerity challenge. So count us in as well!
Good luck with your repairs – may they be easy and cheap!
Thanks for the post, Gavin. The percentage for heating and cooling was surprising for me. Thankfully I am able to do without both especially since my bill is quite high enough but then there are six of us with all but two teenagers. Am working on all the tips.
Thanks for doing this Gavin, it is helpful to concentrate my mind on our consumption. I am part of a very recently retired couple, so I expect our consumption to go up compared to when we were both out of the house all day working.
About 4 years ago we had solar hot water and a 2.2 Kw PV system installed. Unfortunately the only choice then was to feed to the grid – it is not fed to the house and the tariff is much lower than yours – .20 so I envy yours. We live in Brisbane so rarely use heating, but need cooling frequently in the summer. We have ceiling fans in most rooms and air conditioners in 3 rooms. I could really see the difference in our consumption when we used the air con one day and also did some baking one day. The house is on 2 levels. Downstairs is nice and cool on hot days, so we can retreat down there.
Our electricity use so far has been 7-19 Kw from the grid with an average of 11Kw over the week; our PV system has produced 3-14Kw with an average of 8.7Kw.. One day the system only produced 3Kw on our onr rainy November day.
We have struggled with our power company over our accounts. it was difficult to find any one there who had any understanding of solar power. Eventually we found someone who could help us and nine months later they have sent us another account with $445 in credit. He went through every bill over the last year. They don’t seem keen on paying it back though.
This challenge of yours should help us keep an eye on it, thanks again.
Thanks for the tips re: hot water -some are already in place – drips were fixed a year ago, the water saving shower head (also on all the taps in the house), insulated hot water pipes, the hot water heater also has an insulated jacket. I haven’t checked the temp on the hot water heater though, and will do that. Shorter showers – yes, that’s a goal all right, but we have a long way to go, and 2 teenage girls. Wish me luck.
Gavin, help! I received my first bill since going solar and it’s WRONG! They tell me we use 12.46 kWh per day and I know for a fact that we use about 8kWh. Even before your challenge, I was periodically checking it but not recording and it was about 8 kWh. I know many people have trouble with inconsistent numbers on bills. Any advice before I ring and argue with my electricity company?
Hi Everyone, thanks for participating in the challenge so far.
@ Karyn, thanks for joining the TGKWC even if it is by proxy!
@ FSPM, keep up the good work.
@ Coora, you are most welcome. I too have drama with Power companies, but a quick threat to go to the Energy Ombudsman soon puts them straight.
@ Dawn. Good luck in your own challenge of changing teenager behaviours!
@ Linda. My advice is this. Check the date the meter was read on the bill, then see if you read the meter yourself around the same day. That is the evidence you need to call them with. What usually happens is that the meter reader doesn’t try hard enough to get access to your meter and the power company makes an estimate based on your last bill. You can ask for it to be re-read if you believe that they could have read the meter. I have argued the point with my retailer once and got a free re-read.
Also remember that you should compare your bill to both the import and export readings. My first bill after I applied for the feed-in tariff was also totally wrong, but they soon fixed it up. They were not paying the right tariff to me.
Hope that helps
Gav
We had a similar problem with our solar pump. In our case, ours died, and wasn’t pumping water to the roof at all (we have a split system), so we were totally using the electric booster! We had it replaced under warranty.
We’ve also just had a booster switch installed so that we can turn off the electric hot water. This means we are only boosing when we need it, not at 5pm just because we’ve had a shower (and won’t need the hot water again until the sun is up). This has made a noticable difference to our electricity consumption, especially on overcast days. So far, we have had plenty of hot water without having to use the booster.
We’re currently working on trying to shade our east and west facing windows (which are pretty much all of our windows!) so that we can cut down on our air conditioning use. Our house gets very hot, especially in the afternoon.
One cooling improvement we have found very useful is to put reflective film on west facing windows. It made a huge improvement.