Energy - Natural Gas

We have three uses for natural gas in the home, in order of consumption:

1. space heating for the house;
2. hot water service (HWS);
3. cook top.

The space heating only operates in the Victorian cool periods, where the home temperature falls below 10 deg C. that would be from around April to November. Making before and after comparisons with space heating is not easy because of the variables involved. You use more gas in cold winters than in warm ones. We've just had a long cold (relatively, this IS Australia . . ) winter in 2010. But by far the space heater is the massive consumer of gas.

So we'll limit this claim to summer, where the heater is off and our two other gas uses are fairly small and consistant throughout the year.

We've reduced our summer natural gas consumption by 54%, from 29.97 MJ per day to 13.92 MJ per day.

Gas bill Jan-Feb 2007

Gas bill Jan-Feb 2010

How did we do this?

• We removed the existing 300 litre natural gas hot water tank and replaced it with an instantaneous gas water heater.
• The water tank heats to over 60 deg C (as required by regulations), leaves the hot water sitting outside in the open air and has a pilot light running 24x7x365.
• The instant water heater runs only when the hot tap is opened, has no pilot light and only heats to the temperature you select on the control. In our case that's 40-41 deg C for our showers.
• It's also very neat and saves garden space by mounting on the wall.
• We also replaced the old cooktop (sold on eBay) with a newer model as part of the kitchen renovation, but we don't know how much impact that had - probably very little.

The instantaneous gas heater.
Will supply enough hot water for two showers and a tap at same time.
Never runs out of hot water.

One of the three remote controls we have for the heater.
Dial in the temp you want and that's what you get.

More on the space heating

• We used to have a 3 star rated Brivis gas heater which was very basic and had a pilot light running even when it was mid summer. Having a natural aversion to such energy wasters, I'd switch it off, but it was inconvenient at times when the whether fluctuated wildy from hot to cold to hot.
• Eventually I purchased a used 5 star rated Brivis (which look better too!). It has no pilot light, but uses a little more electricity on standby and about double the electricty when in use. So we are using less gas in winter too, but unfortunately more electricity at the same time. Point here is that star ratings aren't everything, it depends what they measure . . .
• I sold the old one on eBay.
• We turned down the house temperature thermostat to 19-20 degrees C.
• BTW - we only heat the downstairs rooms. Upstairs remains unheated aside from a (surprisingly) small amount of warmth which makes its way upstairs and the occasional (3-4 nights a year) use of the reverse cycle AC in heat mode.

Out with the old . . .

 . . . and in with the new (well, second hand).

Brochure pic.