TGKWC – Weekly Confession 3 and Lighting

Now that we are in the last week of the challenge, it is once again time to share your weekly average.

Due to hot weather both day and night for two days our average is just a bit higher than my baseline.  Air-conditioning really is a guzzler of energy .  We recorded average daily usage of 17.6 kWh which is 4% higher than my baseline of 16.6 kWh.  Sometimes you just can’t win a trick!

Oh, I just remembered. The builder was using all of his power tools on Friday (the big spike in the graph), so that would have gone a long way to the large usage we experienced that day.  At least today is looking a lot better with only 13.7 kWh being used.  Our best day so far has been 11.1 kWh, when we were out of the house for most of the day.

Anyway, I hope you have all stuck with it, and tried to reduce where you can and saved a few bucks so far.

So to finish of this post here some information about energy efficient lighting.


Compact Fluorescent Lights

Compact fluorescent lighting now comes in a variety of colours, shapes, sizes and functions including:
• A ‘warm white’ colour, similar in appearance to an incandescent lightglobe suitable for use in living areas, kitchens and bedrooms
• A ‘cool’ white colour suitable for use in bathrooms, toilets and for outdoor use
• Globe, coil and spiral shapes, and now bulbs suitable for reading lamps and chandelier lights. Also available with a glass cover that give them a similar appearance to incandescent lightglobes
• 9 watt (24 watt equivalent) to 18–20 watt (100 watt equivalent)
• Downlight replacements (similar in shape to a halogen downlight).

Compact fluorescent light bulbs are generally available wherever conventional light bulbs are sold, with most hardware stores and major supermarkets stocking a good range. They are usually designed to fit into conventional bayonet or screw fitting light sockets. Specialist lighting stores will stock less conventional bulbs for use in downlights and heritage light fixtures, such as chandeliers.  LED replacements are also becoming more readily available and are getting cheaper all the time.

What about halogen lighting?

Halogen lights are also a type of incandescent light. These are mainly used as downlights in homes. Halogens are also known a “low voltage” lights as they have transformers fitted to convert from the standard household 240 volts to 12 volts, but this does not mean that they are also low energy use.
Halogens are considered an energy intensive lighting option because several halogen lights are often needed in the place of one incandescent or fluorescent light bulb to achieve even lighting levels in a room. (Most low voltage halogen globes used as downlights consume 50 watts each and an additional 15 watts for the transformer).
A 50W halogen downlight used 3 hours a day will cost around $10 a year to run. If you had a room with 8 halogens and ran them for 8 hours each day, it would cost you over $200 every year!
As most halogen lights have a narrow light beam, many more are need to effectively light a room than when using other forms of lighting.  As with incandescent lightglobes, a large proportion of the energy consumed by halogen lighting is actually lost in the form of heat.

Options for Halogen replacements

• In a new home or renovation you can get the look of downlights by installing mini CFL down light fittings. This will cost a bit more, but you will make a big difference to your energy bills and greenhouse gas emissions.
• If you have 50 watt halogen lights downsize them to 20 watt or 35 watt halogen lights to save energy and lighting bills.
• Install a dimmer switch.
• Instead of halogen light consider alternatives such as floor and bench lamps fitted with CFLs.
• If replacing low voltage halogen lights, an electrician will be needed to convert the lights.
• Another technology is LED downlights (LED downlights retail between $30 and $100 each but last up to 50,000 hours). They are currently available from specialist environment stores, online retailers and larger hardware stores. While they are currently quite expensive and the light output and quality may be less than halogen downlights, performance and price is improving all the time.

Energy Efficient Lighting tips

• Natural light is free and the most energy efficient lighting source
• Turn lights off when you don’t need them.
• Replace standard incandescent globes with energy-saving compact fluorescent globes, particularly in high-use areas, and make sure you use the lowest wattage light needed.
• Use programmable timers, daylight sensors or movement sensors to control outdoor and security lighting.
• For outdoor garden lighting, try solar-powered lights.

 I hope that you can use this information and tips to reduce your electricity bill even further.


  1. Dawn says

    Took me a while to tally up the week, but:
    baseline: 29.8
    3rd week average: 33.1
    This is down by 0.3 from last week, so I’m calling it a trend :)
    Next week will not be pretty – we have major construction going on in the basement, think power tools, the light on in that space 24/7 to stop the water pipes from freezing because the exterior wall is missing huge chunks just now, and despite sealing off that space with sleeping bags, plywood etc, the furnace is running a lot more. Sigh. On the upside, our Chrismtas tree etc is up, and the lights are all LED. Last week of school, with kids home next week, I bet our electricity useage will be even higher – I guess we’ll be finishing out the challenge with a real bang…

  2. says

    Hi Gavin,

    Well done inspiring people with this one. I am constantly monitoring the power usage situation to get it down. I don’t however think that just using natural gas is an alternative as it is a fossil fuel. I am also extremely concerned about the use of wood as an alternative fuel. The smoke pollution related issues of wood burning are worrying but can be overcome very easily by burning wood hot and fast thus emitting virtually only water. Most people do not want to do that as it burns too much fuel and instead want to “dampen” the fire which then causes pollution. More to my concern is the deforestation that would come from an increase in home use of combustion stoves but I do have a practical solution below for both of these problems. Here are a few ideas I have been throwing around of late. Rather than trying to cream off small amounts of energy use by switching everything off at the wall etc. or purchasing products that do it for you is a waste of time. As I mentioned to you before in my interview…hot water and cooking accounts for over 70% of my electricity usage (Approximately 15kw per day in total as we have no gas). If I can remove those 2 items I would be using 3-4kw per day and I am generating more than that with solar.


    Cooking is really a hard one. I don’t have a practical indoor solution for an oven (but the “Rocket oven” is a good outdoor oven solution that uses very little wood compared to a pizza oven. Here is a link to a document that also contains info about building solar ovens. Excuse the length of the link. It could be retro fitted for use in a kitchen with a serious makeover.

    The solar oven is certainly a good solution for baking and things that are usually cooked in a slow cooker.

    Here is a great solution for indoor gas cooking on a hob.Bio gas.. I have contacted the company in India about costing and they want $1000 US plus shipping for the smallest unit (1 Cum) which provides up to 4 hours of gas cooking per day providing you can feed it 2kg of waste per day. It would be virtually useless to try and heat an oven with this though.

    Water heating
    I know you already have solar water but I thought I would share this with your readers. has hundreds of plans for solar solutions including water heating which takes care of summer.

    “Milkwood permaculture” have built a “Rocket water heater” but heating water with fire in a container can be house explosively fatal so don’t do it unless you know your s**t.

    House heating
    Again I mention the “Rocket stove”. These are possibly the most most efficient way to create heat with very little fuel. There are people heating their houses (in cold snowy places) all winter long with their garden prunings. I heard about one person heating all winter long with junk mail.
    I just ordered the book and here is the website Alternatively look for videos on “YouTube”.

    Keep up the good work


  3. Michael from Canberra says

    4kWh average over the last week. I found only on Sunday that our stero was left plugged in and constantly drawing 16Wh of standby power from when we played some Christmas music while decorating the tree. This means since the 2nd of December it’s been using 384W per day! That’s almost 10% of our entire bill gone to powering a tiny red light on the stereo. That’s criminal – some things shouldn’t be allowed on the market.

  4. Anonymous says

    Hi Gavin,
    Thank you for your email re: solar panels. we are still procrastinating!

    Processing those cherries was an enormous task but, as you say, so worth it. Thanks for your photos and words on the Fowlers Vacola canning. I have been given a outfit with heaps of jars. What a lovely person to give me that!

Comments build lively communities. Let me know your thoughts, but keep it clean and green! Spam is removed instantly.