On Power
New South Wales' electricity supply is generated by black coal power stations. It has been calculated that the average NSW home uses:
7,300 kWh of electricity a year,
which is derived from burning
3.7 tonnes of black coal,
and causes
8 tonnes of carbon pollution
I've looked at old bills and think that our household used ~5400 kWh/yr before the renovation.
It makes sense to minimise our use of electricity and to use gas or solar energy in preference to coal-fired electricity.
This post covers methods and products which reduce energy consumption; a later post will cover passive energy-efficiency measures which we have designed into the house.
Heating Water
Households use about a third of their energy to heat water.
We already have a solar water heater. It has an electric booster on a timer switch, which we have programmed to go on for two periods a day: 6-8am and 5-8pm (of course the power only runs when the thermostat requires it). This covers our showers and the washing up. I normally wash clothes in cold water, and try to use solar-heated water if I need warm -- that is, I run warm loads in the middle of the day.
Lighting
| INCANDESCENT | HALOGEN | COMPACT FLUORESCENT | LED |
|---|
| Watts Per Equiv. 60w Bulb | 60 | 60 | 14 | 6 |
| Lifespan (hours) | 1000 | 2000 | 15000 | 30000 |
Unfortunately, I cannot remember where all the data for this table comes from; I collected it from various sources. Lighting comprises only about 7% of household energy use, and I imagine that proportion is declining. LED lighting is only just starting to make an impression; give it another ten years and we'll see it take over from compact fluorescents. We've used a number of LED light fittings and the rest are CFLs.
My favourite LEDs are the strips under my cabinets, which I use while cooking. A lovely warm white light and definitely worth the price!
Heating Air
We have not yet installed the gas heater which we think we might need in the family room. This winter will be an interesting test of our passive measures! My Grandmas's draught snake now lies at our front door (that's it up the top). We have also installed beautiful full-length lined curtains, with pelmets, on our family room doors and window. Glass is a very good conductor of heat and needs to be insulated. Proper curtaining provides you with an air layer to buffer the room from the outside. Double-glazing was simply too expensive.
Cooling Air
We have installed a fan in the family room. Sydney's summer humidity makes a fan the best option for a large space. We have retained an elderly air conditioner in our bedroom, but use it rarely. Last summer was so mild that we didn't use the air con and barely used our new fan!
Refrigerating Food
Refrigeration accounts for about 14% of a household's power consumption. We have one fridge and I am considering buying a small chest freezer as my children's appetites get bigger. One of the great hidden electricity users of Aussie households is that old, less efficient fridge, which is moved to the uninsulated garage, filled with beer and (often) left running, in case of an impromptu party.
Apparently, 40% of freestanding Australian homes have a "beer fridge"!
Household Appliances and Entertainment Equipment (excluding refrigerator)
These are thought to account for about 27% of energy consumption, particularly if you don't turn them off at the mains.
We chose our appliances by looking at Choice magazine for efficient products that suit our needs.
We now have a dishwasher, which I use once a day. It heats its own water using mains electricity, which is a new cost. My previous dishwasher still operates regularly; it's about 6' tall and needs a kiss to start, rather than a mains connection. Our new grill and range hood are also electric, but we have a new gas oven and stove.
The washing machine is also new. We bought relatively efficient appliances but a top-loader (which uses much more water and energy than a front-loader) is the only sensible option for a busy family with growing children. As is customary amongst Aussies, I own a clothes dryer, but only use it during wet spells.
We have a number of computers but they all have LCD screens, as does the TV. We have not yet replaced our defunct sound equipment. Below is one of the unusual things I asked the builders for:
Most people's sound gear is plugged into a power point located inconveniently behind the equipment, so it's usually left on standby. The black switch you see above will turn off the TV and sound equipment at the mains. From the kitchen. My children have not yet worked out the implications of this, but I am sure they will grasp it when they are teenagers.
Have you worked out any ways to reduce your power consumption?
